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ProQuest Information and Learning 300 North Zeeb Road. Ann Arbor, Ml 48106-1346 USA 800-521-0600
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. EFFECTS OF ADAPTED BICYCLES PLUS FEEDBACK ON THE ACQUISTION, MAINTENANCE, AND GENERALIZATION OF CONVENTIONAL CYCLING SKILLS FOR CHILDREN WITH MILD MENTAL RETARDATION
DISSERTATION
Presented in Partial Fulfillment of the Requirements for the Degree Doctor of
Philosophy in the Graduate School ofThe Ohio State University
By
Tammy L. Burt M.Ed.
The Ohio State University 2002
Dissertation Committee: Approved by . . Dr. David Porretta, Advisor Advisor Dr. Jacqnefme Goodwary College o f Education
Dr. Timothy Heron
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number 3049000
UMf
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ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT
The purpose of this study was to investigate the effect of using a series of adapted
bicycles plus feedback on the acquisition, maintenance, and generalization of
conventional cycling skills by children with mild mental retardation. The children ranged
in agp from 7 to ll years old. Participants were introduced to cycling skills through a
series of four adapted bicycles and one conventional bicycle, designed to allow them to
gradually become accustomed to the dynamics o f cycling. Positive corrective and
positive specific feedback were provided. Feedback focused on three aspects of
performance; (I) pedal rate, (2) head position, and(3) steering participation. Participants
were required to ride each of the bicycles independently for a distance of 12 m, in 3 out
of 5 consecutive trials. Data analysis included visual inspection of graphical performance.
All ten participants (100%) were successful in acquiring conventional cycling skills. Six
of the 10 participants (60%) demonstrated maintenance, while 3 of the 10 participants
(30%) demonstrated generalization of conventional cycling skills. While not achieving
criterion levels for maintenance and generalization, four participants exhibited partial
maintenance levels and seven participants exhibited partial generalization levels. Results
are discussed relative to dynamic systems theory and motor skill development
n
i Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Dedicated to Llovd Thomas Burt, my brother and inspiration
m
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEGMENTS
The author coaid not have completed this manuscript without the assistance and courtesy of many individuals. First, I would like to thank Dr. David Porretta for his expertise and patience over the past few years, as he guided me along my path towards commencement In addition, I would like to extend gratitude to my committee members, Dr. Jacqueline Goodway and Dr. Timothy Heron. To Dr. Jacqueline Goodway, I appreciate your encouragement and thank you for sharing your knowledge and resources relative to dynamic systems theory and motor development To Dr. Timothy Heron, I thank you for your steadfastness, professionalism in teaching and your research design expertise in applied behavioral analysis. I am indebted to Dr. Richard Klein, who provided me with considerable insight and the generous use of his adapted bicycles. Many doctoral students and friends agreed to assist in data collection. I am grateful for your gift of time. Thanks to Ian Pena, Dr.Heather Savage, Chad Crowe, Harriet Amui, Patrick Akuffo, Ismael FIores-Marti, Lloyd L. Burt, Linda Burt, Tricia Lantz, Shea Cusick and Barbara Brenton-Sahr. Finally, I would like to give my warmest thanks to my friends and family who consistently supported my efforts and exhibited supreme patience and understanding. To Timothy Sahr, I thank you for saving me with your computer savy. To Dr. Sue Sutherland, I thank you for your friendship and for accompanying me over much o f this journey. To Heather Savage, you have been a source of many cherished memories and have served as a brilliant “star". I thank you for your warm friendship. To my family, thank you for your unconditional love.
iv
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. VITA
June 2 ,1 9 6 2 ...... Baltimore, Maryland
1984 ...... BA. Physical Education, Andeison University
1997...... M£d. Special Education, Bowling Green State University
1985-1988 ...... Teacher/Coach, Groveport-Madison Schools Groveport, Ohio
1988-1989 ...... Teacher/Coach, Madison Christian School Groveport, Ohio
1991-1995 ...... Recreation Program Director, The Buckeye Ranch Intensive Care Center, Grove City, Ohio
1995-1997 ...... Graduate Research Assistant, Bowling Green State University
1997-2000 ...... Graduate Teaching and Research Assistant, The Ohio State University
2001-presenL ...... Leisure Education Coordinator, The Association for Individuals with Developmental Disability, Columbus, Ohio
FIELDS OF STUDY
Major Field: Education
Emphasis: Adapted Physical Education
Cognates: Research and Pedagogy
V
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS
Page Abstract...... ii
Dedication ...... iii
Acknowledgments ...... iv
Vita...... v
List of Tables ...... x
List o f Figures ...... xi
Chapters:
I. Introduction ...... I
LI Purpose of this Study ...... 8 1.2 Research Questions ...... 8 1.3 Definition ofTerms ...... 9 13.1 Adapted Bicycles ...... 10 1.3.1.1 Bicycle A...... 10 1.3.13 Bicycle B...... 10 13.13 Bicycle C...... 10 1.3.1.4 Bicycle D...... II 1.33 Conventional Cycling...... 11 133 Conventional Bicycle...... 11
3 Review of Literature...... 12 2.1 Motor Skill Acquisition and Performance for Individuals without Mental Retardation ...... 12 23 Motor Skill Acquisition and Performance for Individuals with Mental Retardation...... 14 23 Dynamic Systems Theory ...... 21 23.1 Skill Acquisition of Individuals without MR...... 21 333 Skill Acquisition oflndividuals with MR...... 27 vi
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 24 Acquisition of Cycling Skills ...... 30 24.1 Training Wheels ...... 30 24.2 Training Aids and Devices ...... 31 25 Teaching Methods/Strategies...... 35 26 Special Olympics ...... 36 2.7 Summary...... 36
3. Methodology ...... 38
3.1 Pilot Stutfy ...... 38 3.2 Participant Selection ...... 39 3.3 Description of Independent Variable...... 42 33.1 Bike A (double-rotter) ...... 42 33.2 Bike B (rear-roller)...... 43 3.33 Bike C (rear-roller) ...... 44 3.3.4 Bike D (fat-tire)...... 44 33.5 Degrees of Freedom ...... 45 33.6 Size of Bicycles ...... 45 3.4 Description ofDependent Variable ...... 45 3.4.1 Distance Traveled Independently ...... 45 3 .4.2 Number of Trials ...... 46 3.43 Downstrokes per Minute ...... 46 3.4.4 Head Position...... 46 3.4.5 Maintenance ...... 47 3.4.6 Generalization ...... 47 3.4.7 Social Validity ...... 47 3.5 Procedures ...... 48 3.5.1 Pretest...... 50 3.5.2 Acquisition ...... 51 3.5.3 Generalization Probes ...... 53 3.5.4 Bicycle Probes ...... 54 333 Maintenance/Generalization Session...... 54 3.6 Interobserver Agreement...... 55 3.7 Treatment Integrity and Procedural Reliability ...... 56 3.8 Experimental Design ...... 57 3.9 Social Validity ...... 57 3.10 Data Analysis ...... 58
4. Results...... 59
4.1 Interobserver Agreement...... 59 42. Procedural Reliability...... 62 4.3 Participant 1 ...... 62 43.1 Distance and Trials ...... 62 4.3.2 Downstrokes per Minute...... 64 4 3 3 Head Position...... 66 vii
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 4.3.4 Summary...... 68 4.4 Participant 2 ...... 68 4.4.1 DistanceandTrials ...... 68 4.4.2 Downstrokes per Minute ...... 70 4.4.3 Head Position ...... 70 4.4.4 Summary...... 63 4.5 Participant 3 ...... 73 4.5.1 DistanceandTrials ...... 73 4.5.2 Downstrokes per Minute ...... 75 4.5.3 Head Position...... 77 4.5.4 Summary...... 79 4.6 Participant 4 ...... 79 4.6.1 DistanceandTrials ...... 79 4.6.2 Downstrokes per Minute ...... 81 4.6.3 Head Position...... 81 4.6.4 Summary...... 84 4.7 Participont5 ...... 84 4.7.1 Distance and Trials ...... 84 4.7.2 Downstrokes per Minute ...... 87 4.73 Head Position ...... 87 4.7.4 Summary...... 90 4.8 Participant 6 ...... 90 4.8.1 DistanceandTrials ...... 90 4.83 Downstrokes per Minute ...... 92 4.83 Head Position ...... 94 4.8.4 Summary ...... 94 4.9 Participant 7 ...... 96 4.9.1 Distance and Trials ...... 96 4.9.2 Downstrokes per Minute ...... 98 4.93 Head Position ...... 100 4.9.4 Summary ...... 100 4.10 Participant 8 ...... 102 4.10.1 Distance ami Trials ...... 102 4.10.2 Downstrokes per Minute ...... 104 4.10.3 Head Position...... 106 4.10.4 Summary...... 108 4.11 Participant 9 ...... 108 4.11.1 DistanceandTrials ...... 108 4.113 Downstrokes per Minute...... 110 4.113 Head Position...... 110 4.11.4 Summary...... 113 4.12 Participant 10 ...... 114 4.12.1 DistanceandTrials ...... 114 4.12.2 Downstrokes per Minute...... 116 4.123 Head Position...... 116 4.12.4 Summary...... 119 viii
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 4.13 Overall Summary of Resuhs ...... 119 4.14 Social Validity...... 121
5. Discussion...... 123 5.1 Research Questions...... 123 5.1.1 Research Question 1 ...... 123 5.1.2 Research Question 2 ...... 132 5.13 Research Question 3 ...... 133 5.1.4 Research Question 4 ...... 135 5.13 Research Question 5 ...... 138 5.2 Limitations ...... 140 53 Implications for Practice ...... 142 5.4 Future Research...... 145 53 Summary...... 145 List of References ...... 148
APPENDICES
APPENDIX A-Bicycie Photographs ...... 160 APPENDIX B-Adapted Bicycle Description...... 164 APPENDIX C-DIustrated Patents ...... 166 APPENDIX D-Pilot Data ...... 173 APPENDIX E-Behavioral and Social Sciences Human Subjects Institutional Review Board (IRB) ...... 179 APPENDIX F-Informed Consent ...... 181 APPENDIX G-Floor Diagram ...... 173 APPENDIX H-Data Collection Sheets ...... 175 APPENDIX I-Procedurai Reliability Checklist ...... 189 APPENDIX J-Social Validity Questionnaire...... 190 APPENDIX K-Interobserver Agreement Observation Schedule ...... 191
DC
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES
Table Page
1 Participant Profiles ...... 40
2 Interobserver Agreement (Percent Agreement) for Distance by Trial ...... 60
3 Interobserver Agreement (Percent Agreement) for Downstrokes per Minute..61
4 Interobserver Agreement (Percent Agreement) for Upright Head Position ...... 61
5 Procedural reliability by participant across all sessions. The values represent the percent of number of “yes” answers on the procedural reliability checklist...... 62
6 Summary of results including participant numbers, trial per bike, total trials, ability to maintain and generalize skill, bike size, mean downstrokes per minute (dpm), and mean percentage of upright head position (uhp) during maintenance ...... 120
7 Mean elapsed time and range in seconds by bike ...... 120
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES
Figure Page
1 Distance traveled in meters, by bike, trial, session ( ) (Participant#!).. 63
2 Downstrokes per Minute, by bike and trial (Participant #1) ...... 65
3 Percent Upright Head Position, by bike and trial (Participant # 1) ...... 67
4 Distance traveled in meters, by bike, trial, session ( ) (Participant #2).. 69
5 Downstrokes per Minute, by bike and trial (Participant #2) ...... 71
6 Percent Upright Head Position, by bike and trial (Participant #2) ...... 72
7 Distance traveled in meters, by bike, trial, session ( ) (Participant #3).. 74
8 Downstrokes per Minute, by bike and trial (Participant #3) ...... 76
9 Percent Upright Head Position, by bike and trial (Participant #3) ...... 78
10 Distance traveled in meters, by bike, trial, session ( ) (Participant #4).. 80
11 Downstrokes per Minute, by bike and trial (Participant #4) ...... 82
12 Percent Upright Head Position, by bike and trial (Participant #4) ...... 83
13 DistancetraveIedinmeters,bybike,triaI,session( ) (Participant #5).. 85
14 Downstrokes per Minute, by bike and trial (Participant #5) ...... 88
15 Percent Upright Head Position, by bike and trial (Participant #5) ...... 89
16 Distance traveled in meters, by bike, trial, session ( ) (Participant #6)... 91
17 Downstrokes per Minute, by bike and trial (Participant #6) ...... 93
18 Percent Upright Head Position, by bike and trial (Participant #6) ...... 95 xi
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 19 Distance traveled in meters, by bike, trial, session ( ) (Participant#?).. 97
20 Downstrokes per Minute, by bike and trial (Participant #7) ...... 99
21 Percent Upright Head Position, by bike and trial (Participant #7) ...... 101
22 Distance traveled in meters, by bike, trial, session ( ) (Participant #8).. 103
23 Downstrokes per Minute, by bike and trial (Participant #8) ...... 105
24 Percent Upright Head Position, by bike and trial (Participant #8) ...... 107
25 Distance traveled in meters, by bike, trial, session ( ) (Participant #9).. 109
26 Downstrokes per Minute, by bike and trial (Participant #9) ...... I l l
27 Percent Upright Head Position, by bike and trial (Participant #9) ...... 112
28 Distance traveled in meters, by bike, trial, session ( ) (Participant #10).. 115
29 Downstrokes per Minute, by bike and trial (Participant #10) ...... 117
30 Percent Upright Head Position, by bike and trial (Participant #10) ...... 118
xn
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER I
INTRODUCTION
The Surgeon General’s report (United States Department o f Health and Human
Services [USDHHS], 1996) addressing physical activity and health reports that
significant health benefits can be obtained by including a moderate amount o f physical
activity into our daily lives. The recent emphasis on the amount, rather than the intensity,
of physical activity makes it more inviting and increases activity options for people in
order to become active and healthy. Numerous physiological benefits involving the
musculoskeletal, cardiovascular, respiratory and endocrine systems can be attributed to
increased physical activity. Health benefits include, reduced risk of premature mortality
and reduced risks of coronary heart disease, hypertension, colon cancer and diabetes
mellitus. Other positive effects appearing to be related to regular physical activity are
reduced depression, reduced anxiety, improved mood, and enhanced ability to perform
daily tasks. Despite these findings, and the fact that higher levels of physical activity
result in lower mortality rates, more than 60% of American adults are not physically
active on a regular basis (USDHHS, 1996). Comparatively, people with disabilities are
less likely to report engaging in regular moderate physical activity than are people
without disabilities (USDHHS, 1996).
I
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. More specifically, youngsters classified with mild mental retardation (mild MR)
have had limited opportunities to participate in health related physical fitness practices
and are prone to obesity (Eichstaedt, Wang, Polacek, & Dohrmann. 1991). The
recognition that children are surprisingly inactive and that lifetime health patterns are
formed in childhood (Stuck-Ropp & DiLorenzo. 1993) point to the need for interventions
directed toward the enhancement of physical activity in children, particularly children
with disabilities.
One such intervention would be to introduce lifetime activities that would be
beneficial and enjoyable to all members of the population. It is proposed that cycling is
such an activity. Cycling is a popular activity among both children and adults. In a study
by Janz(1991), children and adolescents ranging in age from 6 to!7 years reported that
the largest portion of their leisure time, in rank order, was spent watching television,
bicycling, and playing video games. Considering that bicycling was the only non-
sedentary activity reported, its popularity should be seriously contemplated by health and
fitness advocates as a physical activity intervention. Bicycles are reasonably affordable
and easily attainable in today's society. Cycling offers many benefits beyond the obvious
gams in physical fitness and general health. Cycling is an avenue to increase socialization
with peers, it is an inclusive recreational activity, which all members of a family can
participate in together, it can improve self-confidence and, in terms of practicality,
cycling can serve as a means of environmentally friendly transportation. As an added
note, former President Clinton recently released a report by both the Secretary of
Education and the Secretary o f Health and Human Services (National Center for Chronic
Disease Prevention and Health Promotion, 2000), seeking to promote physical activity
2
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. through a variety of strategies such as redesigning communities to facilitate walking and
bicycling. There are currently over 700 miles o f bicycle paths and lanes in the state o f
Ohio alone (Ohio Department of Transportation, 2001).
Unfortunately, many individuals, especially those with disabilities, have never
learned to ride a bicycle (Joules, 1996). Children with MR are often characterized as
being clumsy or awkward. In addition, children with MR may lag behind typically
developing children, in tom s of developmental milestones, by two to four years
(Holland, 1987). In tests of eye/hand coordination, static balance and body coordination,
Eichstaedt, et a!.. (1991) reported that children with mild or moderate MR scored
significantly lower than children without MR. In fact, in a study o f motor proficiency of
children with moderate levels of MR, Job ling (1998) found balance to be the weakest
characteristic, followed closely by bilateral coordination and response speed. Due to
deficits in balance and coordination, children with MR experience difficulty in learning
and performing motor tasks, especially when task complexity increases (Wade, Newell,
& Wallace, 1978) and the task requires a temporal response (Kail, 1992; Newell, Wade,
& Kelly, 1979).
It is estimated (Joules, 1996) that approximately 10 % of the adult population or
28,368,954 individuals (Populations Estimates Program, 2001) have not yet acquired the
skill ofbicycle riding Ziglar and Hodapp (1986) estimate that between 2% and 2.5% of
the population are classified as possessing MR. This accounts for 5 to 7 million people
with MR in the United States. O f this figure, the number of young children with MR who
3
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. have not learned to tide a bicycle is probably significant For some children, it takes
many frustrating years to join their peers on a two-wheeled bicycle. However, many are
left behind in this “rite of passage”.
Statistics from Ohio Special Olympics, indicate that only 191 individuals with
MR compete in cycling events compared to 7,989 competitors in track & field events and
7,481 competitors in bowling events (M.S. Allen, personal communication, May, 2002).
It is difficult to pinpoint why there is such a low number of cycling participants compared
to other sports opportunities. Hypothetically, it could be attributed to lack of equipment,
finances, or programming However, perhaps a larger number of individuals with MR
would actively participate in cycling programs if learning to ride were not such a difficult
task. At this point, however, no empirical research has been found specifically addressing
the learning of cycling skills for individuals with MR
Several theories exist (Schmidt, 1982) which pertain to the learning of
movement/leisure skills, one of which is dynamic systems theory. This theory has direct
relevance to the learning of motor skills for individuals with mental retardation/
developmental disabilities (Gallahue, 2000; Thelen & Smith, 1994; Ulrich, Ulrich &
Angulo-Kinzler, 1998).
Dynamic systems theory originated through Bernstein's (1967) ideas related to the
notion of coordmative structures. In addition, the writings of Easton (1972), Greene
(1972), Kugler, Kelso and Turvey, (1982), and Turvey (1977) have contributed to the
early development o f this theory. More recently, the writings of Caldwell and Clark
(1990), Corbetta and Vereijken (1999), Kamm, Thelen, and Jensen (1990), Kelso, Ding,
and Schoner (1993), Thelen (1989), and Thelen and Smith (1994), have contributed to the
4
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. theory’s refinement According to dynamic systems theory, a variety of systems interact
with our nervous system to create human movement These would include, but are not
limited to such factors as gravity, motivation, body position and context in addition to
the skeletal, muscular, and neurological systems (ail of these factors are important in
learning to ride a bicycle). All aspects of the environment performer, and the task are
constantly changing and interacting. Dynamic systems theory posits that "systems
undergoing change are complex, coordinated and somewhat self-organizing" (Clark &
WhitaiL, 1989, p. 190). In fee t dynamic systems theory has been described as an explicit
theory of change, devoted to uncovering structural and behavioral transitions that occur
in living systems (Corbetta & Vereijken, 1999).
Several complex and technical descriptions of dynamic systems theory exist
involving unfamiliar terminology and mathematical equations (Jeka & Kelso, 1989;
Kelso etaL, 1993). However, an understandable explanation of dynamic systems theory
as it applies to the study of development and learning in sport/leisure, is offered by
Corbetta and Vereijken (1999). Change in behavior is described in terms of stability and
instability. Behavioral states or identifiable forms of behavior are considered to be stable,
while transitions from one behavioral state to another are described as being unstable or
in flux. Environmental and/or internal modifications can bring about instability m a
movement system. It is during these periods of instability that the movement system
becomes more flexible, and new modes of functioning are likely to emerge. Moreover,
Kelso et ai., (1993) recognized that unstable patterns are generally considered as
predictors of change. Preferred modes of coordination, known as attractor states, that
occur before and after periods of instability or transition are comparatively stable and
5
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. resilient to change. To date, the primary focus of developmental and learning studies has
been on the behavioral states or stable periods of a system in change. Dynamic systems
theory shifts the focus from stage-oriented studies to understanding the processes of
change. From this perspective, the primary attraction focuses on periods of instability and
the elements that elicit transition from one behavioral state to another.
It is believed that both stability and instability are the result of self-organizing
processes, as opposed to prescriptive explanations involving motor programs or neural
maturation (Corbetta & Vereijken, 1999). Order emerges through the interaction of the
many components that make up a complex system. There are numerous ways in which
these many components may come together. These various combinations are referred to
as degrees of freedom. For example, an individual has several options to choose from
when the task involves moving from point A to point B. One could walk, crawl, hop, roll,
gallop, skip, run or ride a bicycle to complete the task. This is just a sampling of the
many locomotor combinations or degrees of freedom available to a person. However,
constraints related to the environment, the individual, or the task, have the power to
reduce the degrees of freedom available. If the individual was required to balance an egg
on a spoon while moving from point A to point B, this constraint would reduce the
number o f options available to complete the task successfully.
Two methods that have provided useful insights into the dynamic organization of
behaviors are (a) perturbing the system by provoking sudden changes in the environment
(Schoner, 1995), or (b) inducing a progressive change in the environment following a
steady continuum, until the system makes a shift to another mode of functioning (Kelso,
1995). Corbetta and Vereijken (1999) point out that both methods have been successful at
6
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. identifying stability and predicting change in a system. In addition, these methods have
demonstrated that the system is capable o f spontaneously developing preferred modes o f
coordination to fit new environmental constraints without specific initial intent or
prescription.
From the standpoint o f dynamic systems, the use of a series of adapted bicycles
would represent a progressive change in the task at hand. In this study, the effects of an
adapted bicycle intervention on the acquisition, maintenance, and generalization of
conventional cycling skills for children with mfld MR were examined. Positive corrective
and positive specific feedback was provided across three dimensions (pedal rate, steering
participation, and head position) across five bicycles. A series o f four adapted bicycles
(see Appendix A) developed by Dr. Richard Klein were utilized by a child to gradually
progress toward successfully riding on a conventional two-wheeied bicycle. The adapted
bicycles feature an assortment of specially designed rollers, wide tires and lower gear
ratios, which serve to slow down the tipping rates and forward motion of the bicycles. A
detailed description of the adapted bicycles appears in Appendix B.
The presentation of a gradual continuum of change would encourage a shift to a
more advanced mode of functioning At the onset, the modification o f bicycle response is
crucial in terms o f compensating for significantly slower reacrion times (Distefano &
Brunt, 1982; Surburg 1985) and balance difficulties (Jobling 1999; Krebs, 2000 )
exhibited by children with MR. Forward speed and tipping rate are tempered to allow
children the opportunity to experience the dynamics of cycling in more forgiving and
appropriate conditions. However, as each bicycle in the series is introduced, the dynamics
change to provide increasingly less stability. Essentially, there are more degrees of
7
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. freedom available to perform the task. This brings more flexibility to the system. The
resulting instability allows fertile formation o f new behavioral patterns, in this case, the
ability to successfully tide a conventional bicycle.
Indeed, systems undergoing change are complex. All aspects of the performer, the
task and the environment must be considered in the acquisition of new skills. In
addressing the unique needs of individuals with MR, it is proposed that learning to ride a
bicycle through equipment modification will become less problematic.
Purpose of this Study
The purpose o f this study was to investigate the effect of using a series of adapted
bicycles on the acquisition, maintenance and generalization of conventional cycling skills
by children with mild mental retardation.
Research Questions
1. Does the use of adapted bicycles by individuals with mild mental retardation affect the
acquisition of conventional cycling skills?
a. How many trials to criterion are required for each bicycle during acquisition?
b. What is the overall direction, degree and extent of variability o f the trend as defined by
the relationship between distance and trial by bike during acquisition?
c. What is the total number of trials to criterion for conventional bicycle riding during
acquisition?
2. Is the riding of a conventional bicycle by individuals with mild mental retardation
maintained following the use of adapted bicycles?
3. Is the riding of a conventional bicycle by individuals with mild mental retardation
generalized to a variation o f the task?
s
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 4. Relative to select variables of dynamic systems theory,
a. What percentage o f intervals does the participant maintain an upright bead position (by
trial and by bike)?
b. What was the number of downstrokes per minute (by trial and by bike)?
5. What is the social value of learning to ride a conventional bicycle through the use o f
adapted bicycles?
Definition o fTerms
The following are operational definitions o f the terms used in this study.
Mild Mental Retardation (mild MR)
In this study, mild MR refers to children who have been designated as
"developmentally handicapped" in the state of Ohio. The current definition o f mental
retardation as established by the American Association on Mental Retardation
(AAMRJ992) states:
Mental retardation refers to substantial limitations in present functioning. It is
characterized by significantly subaverage intellectual functioning, existing
concurrently with related limitations in two or more of the following applicable
adaptive skill areas: communication, self-care, home living, social skills,
community use, self-direction, health and safety, functional academics, leisure,
and work. Mental retardation manifests before age 18.
Note that the term "developmentally handicapped” is soon to be replaced by tue
term "cognitive disability” in the state o f Ohio. Revisions are currently being made to the
handbook of rules and definitions
9
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Adapted Bicycles
In this study, adapted bicycles refer to four specially designed bicycles (see
Appendix A) created by Dr. Richard Klein, professor emeritus of mechanical engineering
at the University of Illinois. Each adapted bicycle is described below:
B icycle A . The "double roller” bicycle features two rollers in lieu of conventional
pneumatic tires. The rollers have been mounted onto a 16 in or 20 in (40.64 cm. or 50.8
cm. tire diameter), single-speed bicycle frame. One roller is located in the front position
and the other is located in the rear position of the bicycle. Both rollers to be used on bike
A have crowns o f36.25 arc-inches (92.075 arc-cm.) (roller #5). The drive train is
modified to convert the design to that of fixed gear as opposed to free wheel or "coaster
brake" system.
B icycle B. The rear roller bicycle is a variation on the two-roller bicycle above. It
features only one roller in the rear position; this roller has a crown o f36.25 arc-inches
(92.075 arc-cm.) (roller #5). The front fork is configured with a conventional front fork
and front tire. The rear roller has a-crown of 90.10 arch inches (228.854 arc-cm.). The
drive train is a fixed gear system.
B icycle C. The second rear roller bicycle is a variation on Bicycle B, in that the
sprocket in the front is larger and the sprocket in the rear position is smaller, allowing the
bicycle to move forward at a quicker pace relative to pedal cadence. In addition, the rear
roller used on Bicycle C has a crown o f26.35 arc-inches (66.929 arc-cm.) (roller #7).
to
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. B icycle ZX The "fat tire" bicycle is a standard 16 in or 20 m (40.64 cm or SO.S cm)
sxzs frame, which features a wide, 16x8x5 in (40.64x20.32x12.7 cm) inflatable garden
tractor style the located in the front position. The rear the is a conventional bicycle tire,
with a conventional drive train.
Conventional Cycling
Conventional cycling refers to the act of riding a typical 16-inch or 20-inch (40.64
cm or 50.8 cm) single speed bicycle (see Appendix A) with pneumatic tires and a free
wheel or coaster brake system, without the use o f training wheels or other assistive
devices.
Conventional Bicycle
The conventional bicycle used in this study is a single speed, 16 in or 20 in (40.64
cm or 50.8 cm) bicycle with pneumatic tires and coaster brakes. This is a child’s size
bicycle and will appropriately accommodate children in the 7 to 11 age range.
it
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTER!
REVIEW OF LITERATURE
For the purpose of reviewing the extant literature relative to this research study,
Chapter Two is divided into five sections. The first section examines a variety of
strategies and practices related to the acquisition and performance of motor skills for
individuals without mental retardation. The second section provides information
pertaining to the acquisition and performance of motor skills for individuals with mental
retardation. The third section addresses dynamic systems theory as it relates to motor skin
acquisition and performance. The fourth section focuses on devices and strategies iitili7prf
in the acquisition of cycling skills. The fifth section provides a summary of the related
literature.
Motor Skfll Acquisition and Performance for Individuals
Without Mental Retardation
Experts in the fields o f physical education, kinesiology, and exercise physiology
have long been interested in understanding the acquisition and performance of motor
skills, in addition to an increased interest in comprehending the underlying processes
involved in learning and demonstrating motor skill proficiency. Early motor skill research
focused on applied tasks such as the learning of telegraphy and Morse code (Bryan &
Harter, 1897,1899X typing skills (Book, 1908X and athletic performance (McCIoy, 1934,
1937). However, motor learning and control research during the 1960rs and I970’s
12
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. directed much attention to novel tasks, not directly related to practical or sport and leisure
skills. During this era, there was a shift to a more process-oriented approach, which led to
an increase in the examination of simple motor tasks (e.g., Iinear-positioning) (Bilodeau,
Bilodeau, & Schumsky, 1959). Currently, however, the emphasis is directed towards an
ecological approach to studying human movement through applied sport and leisure skills
in applied settings. For example, study of motor skills such as juggling (Beek & van
Santvoord, 1992), dart throwing (McDonald, van Emmerik, & Newell, 1989; Yang &
Porretta, 1999), and riding a ski-simulator (van Emmerik, Brinker, Vereijken, & Witing,
1989) is returning. The emphasis in the preceding studies is on the "qualitative changes in
the dynamics o f the movement form in addition to the traditional quantitative or scaling
changes that occur with practice." (Newell & Rovegno, 1990, p. 188).
Although human movement seems somewhat effortless on the surface, tasks such
as running, swimming, playing tennis or riding a bicycle, actually require rather complex
actions. A number of research studies have been conducted (Singer, Lidor, & Cauraugh,
1993; Wulf, McNevin, Fuchs, Ritter, & Toole, 2000) which focused on the principles
related to the acquisition and performance of motor skills and the application of these
principles to instruction. These principles included practice composition (Adams, 1971;
Brown, 1928; Henry, 1960; Knapp & Dixon, 1952; MagilL, 1989; Moxely, 1979; Naylor
& Briggs, 1963; Schmidt, 1975; Wickstrom, 1958; Wrisberg & Ragsdale, 1979); practice
schedules (Baddeley & Longman, 1978; Lee & Genovese, 1988; Porretta & O’Brien,
1991; Shea & Kohl, 1990; Shea, Shebflske & Worchell, 1993); knowledge of
performance/results (Shea et al., 1993; Winstein & Schmidt, 1990); and cognitive
strategies (Adams, 1971; Anshel & Singer, 1980; Epstein, 1980; Gallagher & Thomas,
13
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 1986; Magfll, 1989; Payne & Issacs. 1999; Schmidt, 1975; Shea et aL. 1993; Singer,
1978; Singer, Lidor & Cauraugh, 1994; Weis, Ebbeck & Rose, 1992; Winther & Thomas,
1981).
Motor Skill Acquisition and Performance for Individuals with Mental Retardation
Most research on motor skill acquisition and performance for individuals with
mental retardation has drawn directly from motor learning research with the non-disabled
population. The emphasis in this section will be on motor skill acquisition and
performance for individuals with mental retardation.
It is generally known that children with mental retardation experience difficulty in
learning motor skills. Moreover, performance on a variety of motor skills tends to be
lower and more variable as levels of mental functioning decrease (Bruininks, 1974). As a
result, coordination, balance, and reaction times of individuals with MR have been
investigated over the years. Studies have established that persons with mental retardation
exhibit slower reaction times and movement tunes than do people without MR (Eason &
Surburg, 1993; BCrupski, 1977; Nettelbeck & Brewer, 1981; Surburg, Porretta, & Sutlive,
1995). Furthermore, assessments utilizing the Bnrininks-Oseretsky Test of Motor
Proficiency (BOTMP) revealed that children with Down syndrome performed poorly on
subtests o f balance, response speed, and bilateral coordination (Jobling, 1998). The most
significant and enduring problems children demonstrated were with balancing skills. In a
study ofjumping coordination patterns o f children with mild MR. differences in
coordination and equilibrium control were offered as possible explanations for the
performance deficits displayed (DiRocco, Clark. & Phillips. 1987). The previous studies
14
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. concur with the lower test scores involving eye/hand coordination, static balance, and
body coordination o f students with MR and Down syndrome reported by Eichstaedt et aL
(1991).
One explanation for the apparent difficulty in learning motor skills comes from a
cognitive perspective. Bouffard (1990) suggests that the following factors contribute to
the difficulties in problem-solving as it relates to movement: "a) deficiencies in the
knowledge base or lack of access to it, b) lack of spontaneous use o f strategies, c)
inadequate metacognitive knowledge and understanding, d) lack of executive control or
self-regulation, and inadequate motivation.1* (p. 186). Along the same lines, Belmont and
Mitchell (1987) report that children with MR have problems with learning due to
inadequate nervous activity at the most fundamental level of information processing.
They have termed this difficulty in learning the strategy deficiency hypothesis.
From a practical standpoint, Bouffard (1990) suggests that retention and transfer
o f skills should be emphasized many teaming situation. Therefore, it is important to
teach in appropriate contexts (as close to a natural setting as possible). In addition, ample
practice time should be provided to promote mastery and automaticity. ft is also
recommended that in order to increase movement competence, skills should be taught
through a skill-upgrading program. Initially matching the learner to the appropriate task
will provide successful experiences. As a person experiences success he/she will be more
motivated to continue participation. The principle of optimum perceived difficulty
(Belmont & Mitchell, 1987) applies here as welL It states that"... any variable that
contributes to the task's perceived difficulty will bear a curvilinear relationship to task-
targeted activity" (p. 100). Hence, if a child with MR believes that the task before
15
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. him/her is too easy or too difficult, little energy will be put forth. However, if it is
perceived as being moderately difficult, more effort is evident It is imperative that
teachers carefully gage activities based on students’ abilities. Positive attitudes to
physical activity depend on the development of movement confidence (Griffin & Keogh,
1982). hi turn, positive experiences have an effect on confidence and motivation as well
as self-concept (Harter, 1978).
The problem-solving behavior o f individuals with MR was examined while
performing in a simulated racket sport (Bouffard & Wall, 1991). The object was to
systematically manipulate the amount of information available to the performer to
determine if decision-making rules were utilized. The knowledge about where the ball
would land on the table was manipulated The position the players selected to return the
ball, the type of stroke used and the number of balls hit were all affected by this
knowledge o f ball placement Therefore, the selection of responses was context
dependent Results demonstrated a relationship between knowledge, decision-making and
performance for individuals with mild MR.
As was mentioned earlier, the structure o f practice can have an effect on the
acquisition, retention, and generalization of motor skills. In a study designed to examine
the retention and transfer o f skins in children with mental retardation, input was
organized by utilizing three different practice schedules (Del Rey & Stewart, 1989). The
task involved pressing a button when the last light on a runway was illuminated Blocked,
serial, and random practice schedules were used during the acquisition phase. The results
provided support for both random and serial practice schedules in terms o f retention.
There were no significant findings for transfer. This offers some support to the idea of
16
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. contextual interference. Serial practice and to a larger extent, random practice conditions,
force the learner to differentiate the critical features among tasks (Del Rey & Stewart,
1989). Although support for transfer was not evident in the Del Rey and Stewart study,
Edwards, Elliot, and Lee (1986) and Porretta (1982) did observe transfer findings in
individuals with MR as a result of manipulating the structure of practice sessions.
Additional research studies (Porretta, 1988; Porretta & O'Brien, 1991) examining
contextual interference effects in children with mild MR incorporated the use o f gross
motor skills. In the earlier study (Porretta, 1988) children with mild MR participated in a
beanbag tossing task. Children were assigned to either random, serial, or blocked practice
trials for one day (48 total trials). Although less error was exhibited for both transfer and
retention for children assigned to the random practice group, the difference was not
significant Therefore, results provided marginal support for the use of random practice
for better transfer and retention than other practice schedules. In a similar study, Porretta
and O'Brien (1991) compared three different practice schedules (random, serial and
blocked) relative to a coincidence anticipation task. Participants were asked to swing a
plastic bat at a taut nylon string. The swing was to occur just as the last light in a series of
lights was illuminated. However, in this study, twice the amount o f practice time was
allotted. Practice occurred over two days with 48 trials each day. Results indicated that
significantly less error occurred during both retention and transfer phases for those
practicing in random conditions as compared to blocked conditions. Significant
differences were not found during the practice phase. This study provides more support
for the use of contextual interference effects through random practice for children with
mild MR. It also supports the use of additional practice trials across multiple sessions.
17
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Utilizing cognitive strategies for individuals with mental retardation has also been
examined as a means to enhancing skill acquisition and performance. The use o f imagery
or mental practice was studied in conjunction with physical practice for a striking task
(Porretta & Surburg, 1995). The physical practice plus imagery group performed
significantly better in terms of both accuracy and variability than did the physical practice
only group. This supports the use of imagery practice combined with physical practice for
individuals with mild MR. In a related study, the use of imagery practice was utilized as a
supplement to physical practice in the performance of a throwing task (Surburg et aL,
1995). High and low cognitive demands were also examined in relation to the use of
imagery and physical practice. Forty youngsters with mild MR were randomly assigned
into four groups: low cognitive loading-physical practice, low cognitive loading-imagery
and physical practice, high cognitive loading-physical practice, high cognitive loading-
imagery and physical practice. Results indicated that participants supplied with imagery
practice performed much better than the non-imagery groups. However, the cognitive
loading o f a task did not affect the use o f imagery practice. Overall, the use of imagery
techniques for individuals with mild MR may prove useful in teaching motor skills.
Yang and Porretta (1999) modified Singer's (1986) five-step cognitive strategy for
use with individuals with mild MR. Their four-step strategy is less complicated than
Singer’s and consists o f ready, look, do and score. In their study, three closed gross motor
skills were targeted; the basketball free throw, the overhand softball throw and the dart
throw. Results suggest that the four-step approach was a useful strategy for individuals
is
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. with mild MR in that performance improved during the acquisition phase. Although
performance did not continue to improve throughout the retention phase; participants
were able to successfully transfer performance of skills to different settings.
A study by Porretta (1987) examined the effects o f organized and random
presentation of a movement series by adolescents with and without mild MR. Participants
were asked to move a linear slide to distances of 10-20-30-40- and 50-cm., by grasping
the handle of the slide and moving it from right to left Movements were presented in two
different conditions, organized and random. In the organized condition, participants were
presented with movement distances in sequential order. In the random condition,
movement distances were presented in random order. Although the adolescents with MR
exhibited greater absolute error than individuals without MR, they benefited significantly
from organized presentation of movement distances. Results support the use of
experimenter-presented organization to enhance the recall of movement distances by
adolescents with mild MR Porretta (1987) also examined the effect of response
organization on reaction tune and movement time of children with mild MR Participants
included thirty children with mild MR and thirty children without disability, matched for
chronological age. The task was to touch a button as stimulus lights came on. The three
precued conditions involved hand, direction or midline. In the precue hand condition,
participants were told to use either the right or left hand to depress the button. In the
direction condition, the participants were informed as to which side o f the body the
response would take place. The midline condition, involved knowledge about whether or
not to cross the midline in response to the stimulus. Finding suggest that children with
mild MR had significantly slower reaction times and movement times in comparison to
19
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. the children without disabilities. However, both groups performed similarly in that they
were able to utilize precued hand information as opposed to other precued information.
The relationship between internal attributional statements and perceived physical
competence of children with MR was investigated by Kozub and Porretta (1999). Eighty-
six children with MR, between the ages of 8 and 15, served as participants in this study.
Each child was surveyed, and results indicated that internal attributional statements were
chosen more often by older children compared to younger children. This mirrors the
developmental trend found in children without disabilities. Internal attributional
statements are reflective of a mastery-oriented profile, in that success is linked to ability.
However, in general, both male and female children with MR exhibited an external
attributional profile. This is demonstrated by the tendency to select external rationales for
competent outcomes. This type of profile may have a negative impact on self-esteem and
hinder potential achievement in physical activity. It is suggested that practitioners take
this into consideration when providing feedback and teaching children new motor skills.
Feedback should reinforce the use o f appropriate strategies in the successful completion
of a task. In this way, the child will be encouraged to be internally responsible for skill
acquisition. Reinforcing strategy-based effort will assist in generating a mastery-oriented
profile.
Motor task persistence of children with and without MR was investigated by
Kozub, Porretta, and Hodge (2000). Participants for this study included thirty-one
children with and without MR, matched for chronological age. Each participant was
asked to engage in two novel motor tasks. A persistence score was calculated based upon
the total number of trials and seconds engaged. Results indicated that children with MR
2 0
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. persisted less and attempted fewer trials than the children without MR. It is suggested
that tower persistence scores may be related to external attributional constructs o f
children w ith MR.
Dynamic Systems Theory
The emergence o f dynamic systems theory in the field o f motor studies occurred
approximately twenty years agp (Kelso, Holt, Kugler, & Turvey, 1980; Kugier, Kelso, &
Turvey, 1980; Turvey, 1977). Early human movement research studies that utilized
dynamic systems theory involved skilled adult performance and the coordination of
limited body parts. For example, researchers examined skilled coordination patterns in
tasks such as repetitive flexion and extension o f the index fingers (Haken, Kelso, &
Bunz, 1985; Schoner & Kelso, 1988), bimanual manipulation o f hand-held pendulums
(Kugler & Turvey, 1987; Schmidt, Beek. Trefiner, & Turvey, 1991; Turvey, Rosenblum,
Kugier, & Schmidt, 1986) and the motion o f leg swinging between individuals (Schmidt,
Carello, & Turvey, 1990). Through this body of research, it became evident that dynamic
systems theory could aid in the understanding of movement behavior and coordination.
However, only a limited number o f studies involving the learning of new skills or whole
body coordination have been conducted utilizing dynamic systems theory.
Skill Acquisition of Individuals without MR
There is a growing database supporting the dynamic systems principles in human
motor development and the acquisition of motor skills. In particular, there are a variety of
studies involving infants. Researchers have examined treadmill-elicited stepping o f
infants at various ages in the first year of life (Davis, 1991; Thelen, 1986;
21
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Thelen & Ulrich, 1991), the transition from rocking to crawling (Goldfield, 1989), leg
movements o f pre-term and full-term infants (Heriza, 1988), the relationship between
physical growth and a newborn reflex (Thelen, Fisher & Ridley-Johnson, 1984) and
newborn stepping (Thelen & Cooke, 1987; Thelen & Fisher, 1982). Highlights from
selected studies rooted in dynamic systems theory, involving both infants and adults in
the acquisition of motor skills are detailed below.
In a study involving interlimb coordination, Thelen (1994) demonstrated that
three-month-old infants can modify their current "intrinsic dynamics" (Zanone & BCelso,
1991) into new kicking patterns, when presented with a novel task. Intrinsic dynamics are
preferred modes o f coordination that exist at the start of the learning process (Corbetta &
Vereijken, 1999). Three-month-old infants usually kick with either both legs in alteration
or with single leg kicks. Simultaneous kicking o fboth legs at the same time is less
common (Thelen, 1985). In this study, infants controlled the movements of an overhead
mobile by means o f a string attached to their left ankles. Some infants had their legs
yoked together at the ankle with soft elastic. The elastic allowed kicks to be coordinated
as single, alternating, or simultaneous, but the simultaneous kicks activated the mobile
more vigorously. Results revealed that all infants kicked more and faster when their kicks
activated the mobile, than when they did not Interestingly, only the infants in the yoked
condition increasingly produced simultaneous kicking patterns. Infants were able to shift
their patterns o f interlimb coordination to accomplish a novel, experimentally imposed
task. These findings suggest that an adapted pattern o f movement was assembled in
22
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. reaction to a specific task constraint. Therefore, learning processes, rather than
autonomous brain maturation, may underlie the acquisition of motor skills (Thelen,
1994).
Clark, Whitail, and Phillips (1988) analyzed the organization of interlimb
coordination in newly walking infants with and without support and infants who had been
walking for op to 6 months. Results indicated that the coordinative structure for interlimb
coordination in newly walking infonts is similar to that found in the adult walker. Both
temporal phasing (Le., proportion of tune footstrike to footstrike) and distance phasing
(i.e., proportional distance covered in a single step) were examined. While the average
temporal phasing of the newly walking infants was the same (50% out-of-phase) as that
found in older infants and adults, it was much more variable. Over the first three months
of walking, the variability decreases. Nonetheless, the pattern o f interlimb coordination is
in place at the very onset of walking In terms of distance phasing, the new walkers
exhibited more variability. However, the infants had attained a phasing relationship
similar in variability to adults by three months of age. Interestingly, providing support to
the newly walking infonts brought about significant gams for both temporal and distance
phasing. Thus, reducing the postural demands of the infant reduced the variability of
interlimb coordination. This key observation lends support to the argument that the
dynamical requirements of the upright posture may well contribute to the form of
interlimb coordination in infants.
Utilizing the Philippson phases to represent the walking cycle, Clark and Phillips
(1987) analyzed the step cycle organization of infant and adult walkers at various speeds.
The Philippson cycle consists of four phases involving the components of heel strike,
23
i Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. deep knee flexion and toeoff occurring during swing and stance movements. They
discovered that step cycle organization for infants and adults was almost identical across
all four phases o f the step cycle. Changes in speed also resulted in similar methods of
adjustment between infonts and adults. From a dynamical systems perspective, the
Philippson step cycle is not specified by the central nervous system, rather, it emerges
from the constraints of the task and is based on the physical laws that govern biological
system s.
In a longitudinal study, five children were observed over a two-year period
following the onset of walking (Bril & Breniere, 1992). Investigators were interested in
describing the developmental changes in gait velocity. These changes were then related
to components o f postural stability and velocity. Results indicated that in the first six
months of walking, there was a three-fold increase in the range of speed After the first
six months, range of speed leveled out and remained constant. Step width, on the other
hand, decreased two-fold Initially, the increased velocity of infant walkers is primarily
due to increased step length. After about five months, however, increased velocity is
attributed to increased cadence. Developmentally, there appear to be two phases of
independent walking. During the earliest phase (first five months), infants are integrating
postural constraints into the dynamic necessities o f walking. The second phase is
characterized by fine-tuning o f the gait parameters.
Whitall and Getchell (1995) applied a dynamical systems approach to examine
the development of locomotor skills, specifically, the transition from walking to running.
In a dynamic systems analysis it is important to identify variables that represent the
essence o f a particular behavioral pattern. Kelso and Schoner (1988) refer to these as
24
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. collective variables. The collective variables observed in this study were relative stance,
estimated pathway o f center o f mass, and segmental/joint action, la a comparison o f
walking and running in newly running infants, these variables revealed a relatively
continuous change between the two gait forms over the first few months o f running.
Coordination o f the knee joint was similar between walking and running However,
coordination of the ankle joint was less consistent Data from relative stance and stride
length indicated that vertical and horizontal displacement was not evident These findings
suggest that possible control parameters for newly running infants are strength and
balance. These control parameters are necessary to shift a child into more advanced forms
o f running
Several studies involving adult participants have also examined the acquisition of
motor skills from a dynamic systems perspective (Beek & van Santvoord, 1992;
McDonald et aL, 1989; Newell & van Emmerik, 1989; Schmidt, Treffner, Shaw &
Turvey, 1992; van Emmerik, 1992). Following are descriptions of research studies
involving adults participants and the examination o f skill acquisition such as ski-
simulator movements, drawing novel rhythmic tasks between limbs and juggling.
In a study by Vereijken, van Emmerik, W hiting and Newell (1992), five adult
males practiced slalom-like movements on a ski apparatus. The purpose o f this study was
to test Bernstein’s notions of “freezing” degrees of freedom in skill acquisition
(Bernstein, 1967). Bernstein defined the problem of movement coordination as “the
process of mastering redundant degrees o f freedom” (Bernstein, 1967, p. 127). In learning
a novel task, the student is faced with the enigma of reorganizing the control o f an
overwhelming number of degrees of freedom in order to perform the task successfully. It
25
Ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. is suggested by Bernstein (1967) that coordination is brought about by an initial “breezing
out" o f the degrees o f freedom, followed by the subsequent release o f these degrees o f
freedom info the skillful movements o f the performer. In this study, data were collected
across seven consecutive days, via the placement of LED markers on major joints o f the
upper body and legs. Results indicated that in the early phases o f learning, the joint
angles of the torso and lower limbs displayed minimal movement, based on range of
movement and standard deviations. In addition, there was evidence of high joint
couplings. With practice, these findings were reversed, illustrating a significant increase
in angular movement and a decrease in the degree ofjoint couplings. These findings lend
empirical support to Bernstein’s notion o f freezing and releasing degrees o f freedom in
the acquisition of a motor skill. Likewise, in a study of involving drawing movements
(van Emmerik, 1992), comparisons between dominant and non-dominant limbs indicated
significantly higher coupling between joints of the non-dominant limbs. This finding
signifies a comparable freezing out of the degrees of freedom in solving the coordination
problem, in that rigid coupling was evident in the earlier stages o f practice.
In a study involving adult participants, Beck and van Santvoord (1992) conducted
a dynamical systems analysis on learning to juggle. By focusing on the temporal
constraints ofjuggling, they managed to create a mathematical model, or description of
the process of learning the cascade juggle. As opposed to a purely intellectually
constructed motor program, Beek and van Santvoord (1992) have drawn attention
towards the dynamical principles at work
26
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. in skill acquisition. Ultimately, what they discovered was that learning a new motor skill
involves the discovery o f fixed points in the perceptual-motor workspace associated with
that skill, from which deviations can be made in an attempt to further refine the skill
Skill Acquisition of Individuals with MR
Based on the principles o f dynamic systems theory, behavior that is unstable is
more easily shifted into new patterns. It is during these transitional periods as opposed to
more stable periods, that perturbations to the system are more likely to cause change.
Ulrich et aL, (1998) put this principle to the test in a study that examined the impact of
context manipulations on the stepping response of infants with Down syndrome during a
transitional period- Twelve infants with Down syndrome (mean age of 13.3 months) were
tested To examine the type and number of steps that would be produced, each infant was
held upright on a small treadmill. The four context manipulations were referred to as
velcro, nubbly, girdle and weights. It was thought that these manipulations would
enhance the production o f alternate stepping over other stepping patterns, in addition to
an overall increase in the total number of steps taken.
The velcro condition consisted of a carpeted treadmill surface in combination
with the use of socks with velcro strips sewn onto the bottom. It was predicted that the
velcro would keep the foot in contact with the carpeted belt longer and in turn strengthen
the interaction between the extensor muscle forces of the infant and the moving belt The
nubbly condition featured a rubber belt with small projections in combination with bare
feet The resulting ticklish sensation was thought to encourage the infants to step mote
quickly. The girdle condition involved a smooth treadmill belt and bare feet similar to
baseline conditions. In addition, the infant wore a belt the covered the hiprtower back
27
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. area. This manipulation was considered due to the fact that infants with Down syndrome
tend to have greater hip and pelvic instability. It was felt that by stabilizing the lower
lumbar-sacral area, thigh abduction would be minimized. The weights condition was also
performed on a smooth treadmill belt and bare feet However, terrycloth cuffs holding a
small weight were attached to each ankle. The prediction was that by adding mass to the
ankle, more forward movement would be produced.
Results indicated that with the altered conditions, infants produced more total
steps and more alternating steps as compared to baseline conditions. The velcro condition
had the greatest impact of all the context manipulations. In addition, the changes in
context also had a significant effect on the trajectory o f foot displacement in swing. This
research demonstrates the utility o f extrinsic factors on the development of motor skills.
In addition, it provides an increased understanding of behavior during transitional
periods, since transitional periods are an optimal time to effect movement changes.
In an earlier study, Thelen (1986) demonstrated that infants without disability
could produce alternating stepping patterns while supported on a moving treadmill prior
to independent walking or standing. In a similar vein, Ulrich, Ulrich, and Collier (1992)
investigated the ability of infants with Down syndrome to produce organized stepping
patterns on a treadmill. Results show that six o f the seven infants responded to the
treadmill stimulus by producing alternating steps. These findings support those ofThelen
(1986) in that the maturation of the central nervous system is not the only component
necessary in the development of upright locomotion. While leg strength and balance are
factors that may prevent children without disability to walk at earlier ages, for children
28
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. with Down syndrome additional factors may add to the delay. For example delayed
postural reactions (ShumwayCook & WooDacott, 1985), joint laxity (Livingston &
{first, 1986), difficulty in regulating muscle stiffness (Davis & Kelso, 1982) or being
overweight (Chumlea & Cronk, 1982).
In an examination of the mechanical properties underlying movement control of
children with and without Down syndrome, 13 participants took part in a finger
positioning task (Davis & Kelso, 1982). In this two-part study o f a simple, discrete
movment, it was revealed that the gross organization of movement was very similar
among children with and without Down syndrome. However, important differences were
noted, relative to damping and stiffness. Damping refers to the oscillatory behavior about
a newly established equilibrium position. Participants with Down syndrome were less
accurate in controlling these movements, and there was a tendency towards
underdamping. In addition, individuals with Down syndrome were less able to regulate
stiffness with increasing levels of torque, than were participants without Down syndrome.
In summary, although there appears to be overall similarities in the gross organization of
motor control for individuals with and without Down syndrome, movement patterns were
qualitatively different.
Shumway-Cook and Woollacot (1985) investigated the dynamics of postural
control in children with and without Down syndrome This study examined six children
with and 11 children without Down syndrome. Participants stood on a hydraulically
controlled platform and were monitored through the use of surface electromyograms.
Findings suggest that both groups of children produced similar directional responses to
2 9
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. platform movements. However, children with Down syndrome exhibited increased
variability in patterns, slower reactions and increased body sway in comparison to
children without disability.
Acquisition o f Cycling Skills
Training Wheels
A very popular method for introducing cycling skills to young children has been
the use o ftraining wheels. Training wheels assist in keeping the novice rider in an upright
position, however, training wheel use is actually counterproductive in learning how to
balance and ride a conventional bicycle (RX. Idem, personal communication, October,
1998). The use of training wheels promotes inappropriate feedback responses. As a child
rides with training wheels, the tendency is to lean to one side or the other as the bike
moves forward on three wheels (two cycle wheels and one training wheel). This in turn,
results in a preoccupation with the upper torso as a balancing mechanism. This tendency
is very noticeable, as upper-body articulation is quite pronounced when observing a child
attempting to balance a two-wheel bicycle after many years on training wheels. Upper-
body articulation can be described as the shifting o f the shoulders to one side or another.
Finally, the use of training wheels tends to promote a false sense of security. The
bicycle and rider maintain an upright position, regardless o f the technique or movements
employed. If the rider of a bicycle with training wheels does fail, the injuries tend to be
more serious when compared to falls from a bicycle without training wheels (Joules,
1996). This is due to the wide position o f training wheels. When the bike does tip, the
30
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. child is propelled off and upper body injuries are more common. On the other hand, when
falling from a tw o-w heeled bicycle, the legs can slow the fall and injuries to the lower
body are mote common (Joules, 19%).
In terms o f achieving balance on a conventional bicycle without training wheels,
the appropriate technique requires one to steer in the direction o f the fall or lean. Roberts
(1995) explains that the track of a bicycle is not a straight line, but one of constant lateral
undulations. The reason for these oscillations is that any tendency to fall to one side or
the other is promptly arrested by a corresponding horizontal movement in the same
direction. With this in mind, balancing a bicycle is much easier and more productive
when the arms are loose and participating in the steering process. Again, the use o f
training wheels may tend to inhibit this necessary action. The arms are often observed as
being rigid and inflexible as a result of a preoccupation with the upper-body as an
alternate balancing mechanism.
Training Aids and Devices
A complex array of training aids and devices have been developed and patented
over the years, for the discreet purpose of teaching children how to ride bicycles (Egley,
1994; Geller, 1991; Harrison, 1995; Henrichs, 1996; Kalmus, 1994; Krauss, 1993;
Nanassi, 1995; Pearson, 1993; Rieber, 1992; Saunders, 1989) (see Appendix C). Despite
the efforts o f these entrepreneurs, the problem remains unsolved. In each case, the basic
needs o f the learner have not been properly addressed. Rather, in many cases, the
instructor is required to maintain and control balance o fthe bicycle. In addition, an
emphasis is placed on the comfort and upright posture o fthe instructor. Other devices are
simply variations o n training wheels.
31
| Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Patented training devices fall into one o f three categories: (a) harness^ loop or
handle which attaches to the child (Heinrichs, 1996; Nanassi, 1995; Pearson, 1993); (b)
handles which attach to the bicycle (Geller, 1991; Harrison, 1995; Kalmus, 1994; Krauss,
1993) and; (c) alternative training wheels (Egley, 1994; Rieber, 1992; Saunders, 1989). A
brief description outlining the major features o f each training device follows, however,
there is no empirical evidence to support any of the devices described below.
The first category consists of devices that attach directly to the child. The balance
harness (Heinrichs, 1996) is proposed to be useful in teaching cycling, skating, and
mobility skills. The harness consists of two long hoops. One is placed over the child's
head, around the back, and under the arms. The second hoop is then placed under the
arms from the front and across the chest The opposite ends of the loop are held together
above the child's head by the supervising adult Henrichs (1996) suggested that the adult
provide support as the child attempts to ride the bicycle slowly. The adult's role is to
maintain the child’s balance. If the child should start to lose balance, the adult is to lift up
on the harness to bring the rider back to a balanced position.
The Pearson (1993) training device consists of a loop, fitting snugly around the
child’s waist with an attached handle. The device extends behind the child. With the loop
and handle system, the adult supports and controls the balance o f the child as the child
rides the bicycle. Pearson (1993) claims three advantages of the loop and handle system
over conventional bicycle training. First, the adult does not have to stoop over in an
uncomfortable position to hold onto the seat o fthe bike. Second, when holding the
32
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. handle as opposed to the seat, the adult will not overcompensate and control too much of
the child’s weight Third, the loop and handle system is much less expensive to
manufacture than training wheels.
The strap and handle training aid patented by Nanassi (1995) is similar to
Pearson’s (1993) patent with one exception. Nanassi (1995) has added a quick release
system to the handle attachment Otherwise, the two devices are similar in that they
propose to help the cyclist maintain balance.
The next category of training aids can be described as handles, which attach to the
bicycle. Geller (1991) introduced a handle with along shaft that attaches to the lower seat
post and brake bridge. For safety purposes, a braking mechanism has been installed in the
extended handle. Geller (1991) claims that this training device offers several advantages.
First, it provides a comfortable grip for the instructor (no stooping over). Second, the
instructor has full control o f the bicycle because the handle is connected close to the
bicycle’s center of gravity. Third, the instructor is able to provide an immediate response
to correct an abrupt tilt o fthe bicycle. Fourth, the braking system provides a safety
feature to control the bicycle when going downhill.
The Krauss (1993) training device is comprised of a handle that attaches to the
rear wheel fork. The unique features o f this handle include a pivoting head and a
telescopically extendable shaft The handle can pivot up, down and sideways relative to
the bicycle frame. This feature has been included to accommodate the instructor's
preference of running to the left or right side of the bicycle. In addition, the extendable
shaft is adjustable according to the height o f the instructor, thus allowing the instructor to
stand comfortable in an upright position.
33
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The Kalmus (1994) training device is a handle that attaches to the bicycle seat
assembly. This handle is adjustable in both length and angle. The major contribution o f
this invention is to offer a handle that is comfortable for the instructor to grip.
The Harrison (1995) guidance device consists of an U-shaped handle that attaches
to the rear axle and is pivotally adjustable. Harrison (1995) suggested that due to the
location o f the attachment at the axle bolts, it is possible for the instructor to be involved
in the steering to some extent. The objectives, once again, are to provide a comfortable
stance and ultimate control of the bicycle by the instructor.
The last category of training aids consists of alternative training wheel designs.
Saunders (1989) submitted a device that can be described as responsive training wheels.
The training wheels are linked to the front wheel by a cable, causing the training wheels
to raise and lower in response to steering. The advantage is that a more normal leaning
action is simulated than that offered by conventional training wheels.
Reiber (1992) introduced an inwardly adjustable set o f training wheels.
Conventional training wheels are adjusted upwards as the child develops riding skills.
Inwardly adjustable training wheels offer the advantage o f reducing the amount of
support provided by training wheels while at the same time providing stability. With this
system, the bicycle will not tend to wobble from side to side as when the wheels are
adjusted in an upward fashion.
Egley (1994) patented an adjustable training wheel apparatus that incorporated a
compressed spring assembly to dampen axial movement Egley (1994) claimed that tins
device more closely approximates the actual degree o f balancing necessary to ride a
bicycle without training wheels.
3 4
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In addition to training devices or aids that attach to the learner or to the bicycle,
Cudmore (1972) patented a "velocipede" (see Appendix C), which is a two-wheel bicycle
with a barrel-shaped, inflatable, wide rear tire. The velocipede is stable like a tricycle, yet
rides like a bicycle.
Teaching Methods/Strategies
Joules (1996) has actually patented a teaching method for the acquisition of
cycling skills. This method consists o f two phases, an operant conditioning phase, and a
launch phase. During the operant conditioning phase, the instructor straddles the back tire
of the bicycle, while the child sits on the bicycle with feet on pedals and hands on handle
bars. This is a static balance drilL When the instructor causes the bicycle to lean to the
right, the child is instructed to react by turning the handlebars in the same direction as the
lean. When the bicycle leans to the left, the child is instructed to react by turning the
handlebars to the left During the launch phase, the instructor pushes the bicycle away,
and allows the child to practice dynamic balance on a moving bicycle. This method
maintains a prerequisite o f a one second reaction time when a bail is tossed to one side or
the other of a child The child is not required to catch the ball, but merely to react to it by
turning in the appropriate direction. However, there have been no empirical studies to
determine whether or not this method is better than other twanhmg methods/strategies.
Bicycling Magazine (1991) has made available a pamphlet providing instruction
on how to teach a child to ride a bicycle. This method has two phases. In the first phase,
the seat is lowered so that the child can touch the ground. The child is to coast down a
slight incline with feet extended and off the pedals. During this time, the child is to
practice balancing. The instructor is not to run along beside the bicycle. In the second
35
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. phase, the seat is raised to the appropriate height and the child is instructed to pedal as the
instractorholds the back ofthe seat and provides an initial push. However, there is no
empirical evidence to support this teaching method.
Special Olympics
Special Olympics International has compiled several training manuals intended to
guide coaches in the instruction of various sport skills. The Special Olympics
International Cycling Skills Manual (1988) is based on the premise that people entering
the program have previously mastered the primary perceptual and motor skills required to
ride a bicycle. Rather than teaching individuals how to initially ride a bicycle, the
program addresses basic fundamentals such as mounting, steering, stopping, bicycle
selection, and maintenance. The short term objectives are to warm-up properly before
cycling, to demonstrate cycling skills in three levels, to adhere to the modified rules of
competitive cycling, to ride the bicycle in a safe manner and to exhibit sportsmanship.
The three levels of cycling skills consist of: a) riding a bicycle with training wheels, b)
riding a bicycle without training wheels, and c) riding a bicycle competitively, hi
addition, the manual offers specific drills, task analysis and tips for conducting a
successful practice session. However, as with previously mentioned training methods, no
empirical evidence masts to determine whether or not the Special Olympics approach is
better than other approaches.
Summary
The review of literature encompassed several topical areas related to the
acquisition o f cycling skills for individuals with nrild MR. The first section examined
strategies and practices utilized by individuals without MR for the purpose o f acquiring
36
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. and performing motor skills. Historically, research in this area has evolved in its focus
from early applied tasks, to a process-oriented approach examining novel tasks, and
finally towards an ecological approach through applied sport and leisure skills in applied
settings. Over the years, these studies have focused on principles including practice
composition, practice schedules, knowledge o f performance/results, and cognitive
strategies. The second section provided information pertaining to the acquisition and
performance o f motor skills for individuals with MR. Many o f the studies in this area
have examined the coordination, balance, and reaction/movement times o f individuals
with MR. In addition, studies have been conducted with emphasis on the structure of
practice, cognitive strategies, and motor task persistence. General recommendations for
improving acquisition and performance of motor skills for individuals with MR point to
an emphasis on retention and transfer, and the provision of ample practice time in natural
settings. In the third section, dynamic systems theory was presented relative to the
acquisition and performance of motor skills. There is a growing database supporting the
dynamic systems principles in motor development and skill acquisition. Numerous
studies are highlighted involving both individuals with and without MR. The fourth
section introduced several devices and strategies, which were developed for the purpose
of cycling acquisition. In addition to training wheels, several alternative training devices
have been patented. These include various combinations of harnesses and handles that
attach either to the bicycle or to the learner. Various teaching methods and strategies are
outlined originating from sources such as Special Olympics and Bicycling Magazine. The
information and research outlined in the previous sections sets the groundwork for a
study of the acquisition o f cycling skills for parsons with MR.
2 7
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. CHAPTERS
METHODOLOGY
This chapter describes the procedures used for the purpose of investigating the
effect o f using adapted bicycles on the acquisition, maintenance, and generalization of
conventional cycling skills by children with mild MR. It contains the following sections:
pilot study, participant selection, description of the independent variable, description of
the dependent variables, procedures, inter-observer agreement, treatment integrity and
procedural reliability, experimental design, data analysis, and social validity.
Pilot Study
A pilot study was conducted. Three females and two males (age range 4-41 years)
participated in the pilot Two participants had a disability (Cerebral Palsy and Autism)
and three participants had no disabilities. All five participants acquired the ability to ride
a conventional bicycle (see Appendix D). Mean trials to acquisition was 153 (range 64-
182) across an average o f 5.2 sessions (range 3-8). All five participants demonstrated
maintenance of the skill at criterion level. However, no participants were able to
generalize the skilL Several changes in methodology took place based upon pilot study
results. In the pilot study a series o f six adapted bicycles were utilized. Essentially, Bike
A was fit with three different configurations o f rollers, Bike B was fit with 2 different
configurations of rollers, Bike C did not exist, rather Bike D was the next bike in the
series, followed by the conventional bicycle. Results indicated that participants did not
38
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. require three versions of Bike A, nor two versions of Bike B. Additionally, it became
obvious that there was a very large gap between Bike B and Bike D. At this point, Dr.
Klein created Bike C as a better transition. Bike C was equipped with a large hoot
sprocket, to increase forward speed in relation to cadence. The original series A -l, A-2,
A-3, B -l, B-2, D and the conventional bicycle utilized in the pilot, were reduced to A, B,
C, D, E (conventional bike). Furthermore, the placement of cones for the generalization
session was reorganized to better accommodate the cognitive level of potential
participants. In the pilot, the cones were arranged in a straight vertical line, and
participants were asked to weave in and out o f the cones. One of the participants did not
understand the task. Therefore, the cones were placed in pairs, so that a zig-zag path
could be more easily visualized Additionally, the verbal command that the investigator
used at the start of each trial was changed from “1,2, 3, Go”, to “Ready, here we go”.
The “1 ,2 ,3 ” signal made some participants more aware ofthe fact that the investigator
was releasing the bicycle. Therefore, a less direct command was utilized Finally, data
were collected via both video-tape and live coders in the pilot study. In the current study
only video-tape coding was necessary as the quality o f the video was sufficient for
coding.
Participant Selection
Ten elementary school students with m ild MR, ranging in age from 7 to II years,
served as participants (Table 1). All participants received special education services and
were identified as developmentally handicapped (DH) by the state of Ohio. In accordance
with the definition o f DH, all participants exhibited deficits in adaptive behaviors.
Eichstaedt and Lavay (1992) define deficits in adaptive behaviors as “outstanding 39
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. limitations in effectively meeting general standards o f maturation, learning, personal
dependence, and/or social responsibility for youngsters o f similar age and cultural group”
(p. 6). Participants had no known physical or sensory impairments that would inhibit
performance o f cycling skills. Participants were purposefully selected based on age and
disability. None of the participants were able to independently ride a conventional bicycle
at the beginning of the study. Participants were identified by identification number and a
first name. The names used were not the actual first names o f the participants.
The research protocol was approved by the Behavioral and Social Sciences
Human Subjects Review Committee of the Ohio State University (see Appendix E).
Consent forms were mailed to the parents or guardians o f the 10 participants (see
Appendix F). The consent form consisted of an explanation o f the proposed study and
required a signature from the parent or guardian prior to the participant's involvement
All consent forms were signed and returned prior to inclusion in this study. In addition,
all participants were asked to give verbal assent o f their participation in the study. Verbal
assent was videotaped in the presence o f the parent/guardian and two witnesses.
I.D. Participant G ender Age H eight C ondition j
1 Jim M ale 10 58 in Asperger syndrome 2 B illy M ale 7 49 in Mild Autism 3 M ary Fem ale 7 48 in Down syndrom e 4 Jack M ale II 59 in Autism 5 Jerem y M ale 9 48 in Down syndrome 6 Bob M ale 8 54 in Down syndrom e 7 Pete M ale 9 51.75 in Developmental Delay S Danny M ale 10 4 8 in Developmental Delay/Cerebral Palsy 9 E rin Fem ale 9 56.5 in Verbal Dyspraxia 10 A llen M ale 9 57 in Mild Autism/ADD Table 1. Participant Profiles
40
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Following, is a profile o feach ofthe participants relative to siblings and prior
experience with bicycles. Jim has one younger sibling, a 4-year-oid sister. Jim has access
to a bicycle at home, and his past experience with bicycles primarily involved riding with
training wheels. He had attempted riding a bicycle without training wheels, but was
unsuccessful. His mother describes him as being very rigid and fearful in his attempts at
riding a conventional bicycle. Billy has three siblings. He is a triplet hi addition to an 11-
year-old brother, he has a 7-year-old brother and a 7-year-old sister. Billy has access to
bicycles at home. His past experience includes riding a tricycle (two years ago). He then
advanced to riding a bicycle with training wheels. Bike riding was slow and without a
particular focus on reaching a destination. He has had limited experience riding a scooter
for short distances. Mary has one older sibling, a 13-year-old brother. She has access to a
bicycle at home. Her past experience involves riding a bicycle with training wheels and
riding a scooter. Jack has two brothers, ages 9 and 12. Jack has access to a bicycle at
home. Jackrs past experience includes riding a tricycle, a “big wheel”, a bicycle with “big
fat” training wheels, and a scooter. He rode the scooter very slowly. Jeremy has two
siblings, a brother age 7 and a sister age 12. He has access to bicycles at home. His
experience includes riding a bicycle with training wheels and previous to that, he rode a
Fisher Price “hot wheels” trike. Bob has two sisters ages 23 and 25. Bob has access to a
bicycle at home. His past experience includes riding a “big wheel”. He was not able to
ride a tricycle or a conventional bicycle. Pete has 3 brothers and I sister who range in age
from 5-14. He has access to bicycles at home. His past experience includes riding a
tricycle and for the past 2 years he rode a bicycle with training wheels. Danny has two
younger brothers, ages 4 and 8. He has access to bicycles at home. His has had numerous
41
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. experiences with bicycles. His mother was very motivated to include Danny on a family
bike ride. At first, he practiced riding on a therapeutic bicycle. Following this, he rode on
a “tag-a-long” bike. The “tag-a-Iong” is an attachment to a conventional bicycle. This set
up is very similar to riding in the second position on a tandem bike. Erin has no sibling.
She does have access to a bicycle at home and experience includes riding a bicycle with
training wheels. Allen has no siblings. He has access to a bicycle at home and his past
experience involved riding a bicycle with training wheels. However, his mother reported
that riding with training wheels was still difficult for him.
Description of Independent Variable
The independent variable for this study was a bicycle intervention (BI) plus
feedback. Participants were introduced to cycling skills through a series of adapted
bicycles (see Appendix A) designed to allow participants to gradually become
accustomed to the dynamics of cycling. The investigator provided both positive
corrective and positive specific feedback based upon individual performance. Feedback
was provided hierarchically on three aspects of performance; 1) pedal rate, 2) steering
participation, and 3) head position. Feedback was given following each trial, while the
participant was not in the act o f riding the bicycle.
Bike A (double-roller)
Bike A featured two rollers in lieu o f conventional pneumatic tires. The rollers
were mounted onto a single-speed bicycle frame. One roller is located in the front
position and the other is located in the rear position of the bicycle. The configuration
consisted of #5 rollers in the front and back positions. The #5 rollers represented the most
stable rollers in that they had they least amount of contour. Bike A had a direct drive or
42
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. fixed gear drive train as opposed to a free wheel or "coaster brake" system. With a direct
drive bicycle; forward motion occurs only when the pedals are moving (this does not
allow for coasting). With a free wheel system, the bicycle can coast forward while the
pedals are stationary. Bike A was the most stable bicycle in the series doe to the weight
and contour of the two rollers. In addition, the gearing was altered sufficiently to slow
forward speed (town relative to pedaling cadence. The bicycle's gearing was about one-
third that o f a conventional similarly sized bicycle. Therefore, participants could
concentrate on pedaling the bicycle without the fear of foiling or the fear of forward
speed.
Bike B (rear-roller)
Bike B is a variation on the two-roller bicycle. It featured only one roller in the
rear position. The front fork was configured with a conventional front fork and front tire.
Roller #5 was used with Bike B. This bike had a direct drive or fixed gear drive train as
opposed to a free wheel or "coaster brake" system.
Bike B was the second bike in the sequence. It was less stable than Bike A in that
it only utilized one roller in the rear position Therefore, the participant had to begin
actively participate in the steering o f the bicycle to maintain balance. Again, the gearing
was altered sufficiently to slow forward speed down relative to pedaling cadence. This
allowed the participant to concentrate on steering participation, without the fear of
forward speed.
43
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Bike C (rear-roHer)
Bike C was the second, rear-roller bicycle. There were two differences between
Bike B and Bike C. First, a #7 roller was used with Bike C. The #7 roller was less stable
than the previous (#5 roller) in that it cut with more contour. Second, the sprocket size on
Bike C was altered, so that the forward speed o f the bicycle was increased relative to
pedal cadence.
Bike O (fat-tire)
Bike O consisted of a standard bicycle frame, which featured a 16 x 6.50-8
inflatable garden tractor tire located in the front position. The rear tire was a conventional
bicycle tire. Bike D operated with a conventional free wheel drive train.
Bike D was the least stable of the four adapted bikes. The width of the fat tire was
about half that of the rollers, although they were similar in weight The gyroscopic action
of the fat tire assisted with stabilization. In addition, Bike D maintained a conventional
drive train. This meant that the forward speed of the bicycle relative to pedaling cadence
was similar to that of a conventional bicycle. The participant was required to actively
participate in the steering while moving at a typical forward speed.
Degrees o f Freedom
As a participant progresses from Bike A to Bike E, the available degrees of
freedom are gradually expanded. This increase in the degrees o f freedom is due to
specific design features o f each bicycle in the progression. For example, from Bike A to
Bike E, the tire configuration changes from very stable rollers, to rollers with more
contour and less stability, to a wide tractor tire, and finally to conventional bicycle tires.
With the change in tires, comes an increase in the degrees of freedom, relative to balance
44
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. and steering participation. The same principle applies in terms of forward speed
allowances along the bicycle progression. Changes in the front crank size and a reduction
in tire friction allow for increasing speed from bike to bike. In essence, are increasing
opportunities in response to the changing dynamics o f each bicycle, which can give rise
to new and adaptive movement forms.
Size of Bicycles
There were two sizes of bicycles available, 16” (40.64 cm) and 20” (50.8 cm).
The dimensions (16”, 20”) refer to the circumference of the tires. Each participant was fit
to a bicycle so that his/her feet could comfortably contact the floor flat-footed. This was
accomplished by adjusting the height of the seat
Description ofthe Dependent Variables
Distance Traveled Independently
The distance traveled independently to the nearest meter on each of the four
adapted bicycles and on the conventional bicycle served as one o fthe dependent
variables in this study. Criterion for each o f the bicycles was riding independently for a
distance of 12 m, in 3 out of 5 consecutive trials. An independent trial was scored when
the participant maintained balance of the bicycle. On bicycles with a conventional drive
train, coasting was permitted. The trial ended when a) the investigator touched the bike or
the participant, b) a foot touched the floor, or c) the front tire of the bicycle touched a
boundary line (see Appendix G). The instructor would intervene to ensure the safety of
the participants. When the bicycle appeared to be tipping over, the instructor would
intervene prior to a fell either by placing her hands on the participants sides and under
4 5
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. the arms, or by grabbing the underside o f the bicycle seat (safety was a priority). Data
involving distance traveled independently were collected through video-tape coding.
Num ber o f Trials
The number of trials to criterion on each o f the four adapted bicycles and on the
conventional bicycle was another dependent variable. Criterion for each o f the bicycles
was 12 m, in 3 out of 5 consecutive trials o f independent riding. Data involving number
o f trials to criterion were collected through video-tape coding.
Downstrokes per Minute
Downstrokes per minute was another dependent variable. The pedal rate
measured in downstrokes per minute (dpm) was another dependent variable. Pedal rate
was reported as downstrokes per minute based on the number of downstrokes per trial,
and the elapsed time for that trial. A downstroke consisted of movement of the foot and
pedal from the top position to the bottom position beginning at the 12 o'clock to 2 o'clock
position and ending at the 6 o'clock position on the crank. When the foot and pedal began
at the 3 o'clock position or lower, a downstroke was not counted.
Head Position
Head position was another dependent variable. Data on head position were
collected by partial interval recording with two-second intervals. If the head was
observed in an upright position anytime during the two-second interval, the interval was
recorded as positive for upright head position. Upright head position was reported as the
percentage o f intervals in which the participant's head was in an upright position. An
example o f upright head position was when the nose was pointed forward (8 o’clock to
10 o'clock position). A non-example occurred when the nose was pointed m the direction
46
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. ofthe floor (6 o'clock to 7 o’clock) or toward the sideline or ceiling (II o’clock to 12
o’clock). These data were collected through videotape observation. Data were collected
during pretest probes and acquisition. Various combinations of head position and pedal
rate have been observed in proficient cyclists as well as in individuals who are initially
developing cycling skills. lit this study, data were collected relative to the stability and/or
instability of the hypothesized attractors involved in the complex skill of cycling.
Maintenance
Maintenance of conventional cycling skills was another dependent variable.
Maintenance is defined as the extent to which a learner continues to perform a target
behavior upon completion of the intervention (Cooper, Heron, & Heward, 1987). In this
study, a maintenance session was conducted to determine the degree to which
participants maintained performance on the conventional bicycle:
Generalization
Generalization was another dependent variable in this study. Response
generalization required the participant to perform a variation of the task. In this case, the
participant was required to navigate through a series of cones (Appendix G).
Social Validity
Social validity data was another dependent variable. At the completion o f the
cycling sessions, a social validity questionnaire was completed by each o f the
parents/guardians of the study participants. Opinions regarding the efficacy of utilizing
adapted bicycles as a learning tool in acquiring conventional cycling skills were obtained.
In addition, opinions regarding the benefits o f acquiring conventional cycling skills
relative to community recreation and leisure were included.
47
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Procedures
Participants rode four adapted bicycles and a conventional bicycle. Participants
attended three, 45 min sessions a week, for a maximum o f five weeks. All sessions took
place inside a gymnasium. Participants were instructed not to practice cycling skills
outside o f study sessions. Parent/guardians were not present in the gymnasium once the
session began. The researcher, two research assistants, and the participant, were the only
persons in the gym at the time of data collection. The research assistants were responsible
for operating the two video-cameras. Participants received individualized instruction.
Initially, a pretest probe was taken to determine the participant's level of performance on
each bicycle progression. Following this, the first bicycle in the series (Bike A) was
introduced. The investigator provided either positive, positive/corrective or
positive/specific feedback relative to the participant's performance on each trial.
Feedback was provided only after the participant had completed a trial and was not in the
act of riding the bicycle. After criterion level performance was reached on a bicycle, one
generalization probe was taken on that bicycle. Following this, one probe of each bicycle
in the progression was taken to determine whether performance changes had occurred in
any other steps. During acquisition, participants rode the bicycles in sequential order (I)
Bike A, (2) Bike B, (3) Bike C, (4) Bike D, and (5) Bike E (conventional bike).
Participants did not advance to the next bicycle in the series untO a criterion level of
performance was reached on the current bicycle. Criterion was set at 12 m of independent
riding on 3 out of 5 consecutive trials. Once a participant met criterion levels on the
conventional bicycle (Bike E), a single generalization probe was taken and the session
48
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. ended. On a separate (by, a maintenance/generalization session took: place. A maximum
o f 15 maintenance and 15 generalization trials occurred during the
maintenance/generalization session. All sessions were video-taped from two angles
using RCA Model CC4362 camcorders. A stationary video-camera was placed at the end
o f the data collection area to capture a front view of each participant. A second video
camera (on rollers) was moved along the sideline to capture a sideview of the participant.
Each trial began at the ready line. The instructor pushed the bicycle forward 13 m
to the starting line. As the front the o f the bicycle touched the starting line, the instructor
released the seat. This is the point were measurement of the trial began. The trial ended
when: (a) the investigator touched the participant or the bicycle, (to intervene prior to a
fall) (b) the participant touched the floor with a foot, or (c) the front tire ofthe bicycle
touched the side boundary line. Upon completion o f each trial, the investigator
announced “stop” and the distance was measured from the starting line to the contact
point o f the lead tire. Gym tape was placed on the floor, (see Appendix G for floor
diagram) in addition to numbered markers, to assist in the measurement of the distance
traveled. At the end of each trial, the investigator asked the child to dismount the bicycle
and walk back to the starting position. Prior to the start of the next trial, the investigator
provided either positive, positive/corrective or positive/specific feedback to the
participant. Feedback addressed the hypothetical attractors of pedal rate, steering
participation or head position. Following is a detailed description of each phase in the
study including scripts.
49
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. The pretest was conducted on a one-to-one (researcher and participant) basis.
When a participant entered the gymnasium, the instructor introduced herself and then
described the purpose of the study. After a brief explanation, the investigator asked for
verbal assent from the participant The investigator said:
“Hi, my name is Tammy. [ teach people how to ride bicycles. I have four special
bicycles that help people learn how to ride a regular bicycle.”
The investigator then showed each of the bicycles to the participant
“Would it be o.k. with you if I taught you how to ride a bicycle?”
Following this, procedures for practice sessions were explained. The investigator said:
“You will get to practice with all of these bicycles. Before you get on a bicycle,
you will have to put your helmet on. We will start by adjusting the seats, so that
they are in the right position for you.”
The seat of each bicycle was adjusted so that the participant could sit on the seat
while his/her feet comfortably maintained contact with the floor.
“First, you will get to try riding each bicycle one time. Then, we will practice on
Bike A. You will start with the bike behind the black tine. You will sit on the bike
and put your feet on the pedals and hands on the handlebars while I hold the seat
from behind. When you are ready, I will help get you started. I will say Ready,
here we go! You just ride the bicycle the best you can. Ride as far as you can.
When you stop, you will get off of the bike and we will walk it back to the
starting line to try again. Do you have any questions?"
50
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. The investigator held the bicycle steady and upright behind the black "ready" line
as the participant mounted the bicycle. On the "Ready, here we go" signal, the
investigator poshed die bicycle forward for a distance of 1.5 m. When the front tire
touched the starting line, the investigator released the bicycle seat The trial ended when
(a) the instructor touched the bicycle or the participant, (b) the participant's foot touched
the floor, (c) the front the o f the bicycle crossed one of the side boundary lines. If a
bicycle began to tip and the participant failed to react appropriately, the investigator
immediately intervened to prevent a fall. Positive feedback was provided during the
pretest probes.
Acquisition
The acquisition phase took place on a one-to-one basis, three days a week, 45
minutes per session. During acquisition, the participant was introduced to a series of five
bicycles (4 adapted, I conventional). The order of progression was Bike A, Bike B, Bike
C, Bike D and Bike E (conventional bike). Instructions were as follows:
“You will start with the bike behind the black line. You will sit on the bike and
put your feet on the pedals and hands on the handlebars while I hold the seat from
behind. When you are ready, I will help get you started. I will say 'Ready, here
we go!’ You ride the bicycle the best you can. Go as for as you can go. When you
stop, you will get off of the bike and we will walk it back to the starting line to try
again Do you have any questions?”
The investigator held the bicycle steady and upright behind the black "ready” line
as the participant mounted the bicycle. Prior to each trial, the instructor reminded the
participant to ride as for as he/she could. On the "Ready, here we go” signal, the
51
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. investigator pushed the bicycle forward for a distance of 1.5 m. When the front tire
touched the starting line; the investigator released the bicycle seat The trial ended when
(a) the instructor touched the bicycle or the participant, (b) the participant's foot touched
the floor, (c) the front tire o f the bicycle crossed one o f the side boundary lines. When a
bicycle began to tip and the participant failed to react appropriately, the investigator
immediately intervened to prevent a fall.
The performance of each participant was closely observed as he/she rode the
bicycle. At the end o f each trial either positive, positive/corrective or positive specific
feedback addressing one of three performance issues (a) pedal rate, (b) steering
participation, or (c) head position was provided. Positive/corrective and positive specific
feedback hierachically addressed pedal rate, steering participation and head position. For
example, if the child was pedaling very slowly, the investigator said, "Good work! This
time, use your feet to pedal faster". In addition to providing verbal feedback on pedal
rate, the participant would occasionally practice pedaling on a stationary bike stand.
When addressing steering participation, a static balance drill was administered in
addition to verbal feedback. With the bike at the starting position and the participant on
the bike (hands on handlebars and feet on pedals), the instructor held the bike seat from
behind with two hands and slightly tipped the bike to the left and to the right while
instructing the child to react by moving the handlebars in the same direction o f the lean.
The investigator said.
“You need to move your arms. When the bike leans this way, you move the
handlebars in the same direction.”
After repeating the static drill three times, the investigator said:
52
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. “Good work! Remember to move your arms!”
If the participant rode with his/her head down or looking towards the sidelines;
the investigator provided feedback related to bead position. The investigator said
“Keep your head up, so you can see where you are going! Look at Curious
G eorge.”
(A sheet with a painting of Curious George was hung at the opposite end of the gym.)
Prior to each trial, the instructor reminded the participant to keep his/her eyes on Curious
George. Once criterion level was met on a bicycle, a single generalization probe was
administered on that bicycle. Following this, one probe was taken on each of the
remaining bicycles in the series and the participant advanced to the next bicycle in the
series.
Generalization Probes
A generalization probe occurred at the completion of criterion level on each
bicycle. Response generalization consisted o f a probe in which the participant was
instructed to navigate the bicycle through a series of cones placed at 1,4,8 and 12 m (see
Appendix G). Prior to the first generalization probe, the instructor demonstrated to the
participant the path that they should take by modeling a single trial. Prior to subsequent
probes, the instructorand participant would walk through the cones to remind the
participant of the correct path to follow. The investigator said:
“This time, you will ride the bike between each set of cones, like this (model one trial).
Now it’s your turn.”
53
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. B icycle Probes
Throughout the acquisition phase, a single probe was taken with each successive
bicycle in the series to determine the relationship between the independent variable and
the successive approximation of the skill o f cycling. For example, once a participant
reached the criterion level for Bike A, a generalization probe was taken using Bike A,
then a single bicycle probe was taken with Bike B, Bike C, Bike D and Bike E
(conventional bicycle) prior to practice on Bike B. In addition, intermittent bicycle probes
were taken throughout acquisition after approximately every 10 trials.
Maintenance/Generalization Session
A maintenance/generalization session took place in the session following
termination of the intervention. This occurred one to two days following acquisition of
conventional cycling skills at criterion level. During maintenance, participants performed
a maximum of 15 trials with the conventional bicycle. If the participant reached criterion
levels after 10 trials, the maintenance session ended. Cooper, Heron, and Heward (1987)
define maintenance as the extent to which a learner continues to perform a target
behavior upon completion o f the intervention. Within the present study, a maintenance
session was conducted to determine the degree to which participants maintained
performance on the conventional bicycle. The instructorexplained the maintenance phase
as follows:
Today, you will be practicing only on the regular bicycle. We will start with the
bike behind the black line. You will sit on the bike and put your feet on the pedals
and hands on the handlebars while I hold the seat from behind When you are
ready, I will help get you started and say ready, here we go? Ride the bicycle as
54
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. far as you can. When you stop, you will get off of the bike and we will walk it
hack to the starting line to try again. Do you have any questions?”
No specific or corrective feedback was provided during maintenance. At the completion
of each trial, the instructor said:
“Good job, let's do it again f”
Prior to each trial, the instructor reminded the participant to ride the bicycle as far as
possible.
After the maintenance trials were completed, the generalization trials began. Each
participant was given a maximum of 15 generalization trials. Again, if the participant
reached criterion levels after 10 trials, the generalization session ended. Response
generalization consisted of trials in which the participant was instructed to navigate the
bicycle through a series of cones placed at 1,4,8, and 12m (see Appendix G). Prior to the
generalization trials, the instructor demonstrated to the participant the path that they
should take by modeling a single trial.
Inter-observer Agreement
The investigator and a physical education doctoral student independently coded
data from the video-tapes. The coding consisted of. (a) number of trials, (b) distance
traveled independently on each o f the five bicycles (Bike A, Bike B, Bike C, Bike D and
Bike E (conventional bicycle), and (c) hypothesized attractors (pedal rate and head
position). The investigator discussed data collection procedures with the second coder
and distributed th e data, sheets (see Appendix H). The second coder attended a practice
session on how to accurately record data on the (feta sheets for video-taped coding.
During this practice session, the investigator and second coder independently coded data
55
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. from the video-tape, then compared and discussed resuits. Coding did not continue until a
minimum o f 90% agreement was reached between the two codecs. The investigator and
second coder discussed any concerns from the practice session. The investigator coded all
bicycle sessions from videotape and the second coder coded one full session for each
participant This inchided sessions across all bikes throughout acquisition, maintenance
and generalization. To ensure accuracy between the observers, the investigator
announced “stop” at the end o f each trial during data collection. Trial by trial agreement
between the two coders was calculated by using the formula:
(Agreement Agreement +■ Disagreement) x (100) = % Agreement).
Treatment Integrity and Procedural Reliability
Treatment integrity refers to the extent to which the independent variable is
applied or implemented as intended (Cooper et al., 1987). To ensure that the independent
variable was presented in an accurate and consistent manner, a procedural reliability
checklist (see Appendix I) was utilized across all session and pertaining to all trials.
Individuals present during the taping o f each session were trained to collect data
regarding all treatment components on the reliability checklist Observer training was
conducted in a live, mock session with the investigator and observers present. During the
training session, the investigator first explained how each trial would progress, step-by-
step. The treatment integrity checklist was introduced and the instructor provided a live
demonstration on the bicycles. Following this, the investigator addressed any questions or
concerns related to treatment integrity and procedural reliability.
56
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Experimental Design
A multiple probe design was used for this study (Cooper et aL, 1987). The
multiple probe design was appropriate for evaluating the relationship between the
independent variables (adapted bicycle intervention plus feedback) and the acquisition of
successive approximations o f a skill (cycling). Specifically, distance traveled
independently, number of trials, pedal rate, head position, maintenance and
generalization. In this study the participants gradually acquired the skill o f cycling as they
practiced on progressively more challenging adapted bicycles. Four adapted bicycles and
a conventional two-wheeled bicycle comprised the instructional series. Rather than
collecting prolonged baseline data on skills that were not yet developed, intermittent
measurements (probes) provided the information necessary to determine whether or not a
change had occurred prior to intervention.
Social Validity
At the conclusion of data collection, a social validity questionnaire was mailed to
the parents/guardians of all study participants. The questionnaire consisted of nine Likert-
scale statements. Opinions regarding the efficacy of utilizing adapted bicycles as a
learning tool in acquiring conventional cycling skills was obtained. In addition, opinions
regarding the benefits o f acquiring conventional cycling skills relative to community
recreation and leisure were included in the questionnaire (see Appendix J). There was a
100% return rate. This required the investigator to provide two parents with a prompt by
phone.
57
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Data Analysis
Visual inspection of the graphs was used to interpret data. Both witiun-phase and
between-phase analyses were conducted Within-phase visual analysis involved a
determination of the number and variability of data points, in addition to the level of
performance and the direction and degree of trends. Between-phase visual analysis, was
conducted to determine changes in level, trend, and degree of variability. Individual
graphics were displayed for each study participant Data were presented descriptively
using means, ranges, and percentages.
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. CHAPTER 4
RESULTS
This chapter presents the results of the effects o f using adapted bicycles on the
acquisition, maintenance, and generalization o f conventional cycling skills by children
with mild MR. Fourteen major sections are included in this chapter. Interobserver
agreement results are addressed in the first section. The second section provides
information regarding procedural reliability results. Sections three through twelve include
data for all 10 participants. Section thirteen presents a summary o f results. Finally, social
validity results are discussed in the last section of this chapter.
Interobserver Agreement
The interobserver agreement percentage for accuracy o f bicycling acquisition
utilizing a series of adapted bicycles and a conventional bicycle was taken across all 10
participants. Session-by-session interobserver agreement data o f distance by trial were
taken from ten sessions across all five bicycles (Bikes A, B, C, D, and E). Sessions were
selected based upon a predetermined schedule to allow for observation of acquisition
across all five bicycles (see Appendix K). Session-by-session interobserver agreement
data of downstrokes per minute and upright head position were taken from ten sessions
across all 10 participants, examining the first session of each participant Table 2 contains
the interobserver agreement percentage for accuracy o f distance by trial for each of the
ten participants- The mean interobserver agreement for cycling distance by trial was
96.4% across ten participants (range 90% to 100%). 59
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Participant IOA fo r D istance
I 100% 2 100% 3 100% 4 100% 5 90% 6 94% 7 93% 8 95% 9 100% 10 92% Mean 96.4%
Table 2. Interobserver agreement (percent agreement) for distance by trial.
Interobserver agreement percentages for accuracy of downstrokes per minute and
upright head position by trial for each of the ten participants are displayed in Tables 3 and
4 respectively. The mean interobserver agreement for downstrokes per minute by trial
was 91.6% across ten participants (range 83 to 98%). The mean interobserver agreement
for upright head position by trial was 78% across 10 participants (range 67 to 88%).
Although and IOA of 90% or better are generally considered adequate for permanent
products, this percentage is arbitrary and must be considered in light of the complexity
and quantity o f observations. Interobserver agreement with an average of 75% is
considered to be adequate for data collected across intervals of 5 seconds or less (Cooper,
Heron, & Heward, 1987).
Reproduced with permission ofthe copyright owner. Further reproduction prohibited without permission. Participant IOA fo r Downstrokes p er M inute I 94% 2 83% 3 83% 4 94% 5 91% 6 97% 7 98% 8 87% 9 93% 10 96% M ean 91.6%
Table 3. Intecobserver Agreement (Percent Agreement) for Downstrokes Per Minute
Participant IOA for Upright Head Position 1 82% 2 86% 3 70% 4 84% 5 70% 6 88% 7 82% 8 67% 9 78% 10 73% Mean 78%
Table 4. Interobserver Agreement (Percent Agreement) for Upright Head Position
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Procedural Reliability
Procedural reliability for this study was established by the use o fa procedural
reliability checklist consisting o f seven questions (see Appendix I). Procedural reliability
data were obtained for every session in the study (total o f 58 sessions). The video-tape
operator completed the procedural reliability checklist at the end o f each session. Across
all sessions for all participants, procedural reliability was calculated at 98.7% (range 94
to 100%). Procedural reliability questions pertained to all trials in a session.
Participant Procedural Reliability Percentage t 100% 2 100% 3 100% 4 100% 5 100% 6 94% 7 100% 8 98% 9 97% 10 98% Mean 98.7%
Table S. Procedural reliability by participant across all sessions. The values represent the percent of number of “yes” answers on the procedural reliability checklist
Participant I
Distance and Trials
Jim rode the 20 in (50.8 cm) size bicycles (A-E) and acquired the skill of riding a
conventional bicycle (Bike E) in one session (29 trials). Figure 1 is a graphic display of
Jim’s acquisition, maintenance, and generalization o f conventional cycling skills across
Bikes A-E. During the pretest trials, Jim rode: Bike A, a distance of 12 m; Bike B, a
distance o f4 m; Bike C, a distance o f I m; Bike D, a distance o f 12 m and Bike E, a
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
DISTANCE/METERS 12 O -i©t Figure I . D istance traveled in m eters, by bike, trial, session ( | ) (Participant #1) (Participant ) | ( session trial, bike, by eters, m in traveled I istance . D Figure I ___ TRIALS 63 distance of 3 m. Following the pretest, Jim immediately met criterion levels on Bike A.
He was also able to generalize this skill at a distance o f 12 m. Likewise, on Bikes B and
C he immediately met criterion levels (12 m). He was also able to generalize this skill on
Bikes B and C (12 m). On Bike D he immediately met criterion levels. The generalization
probe elicited a distance of 1 m. Again, on Bike E he immediately met criterion levels (12
m). Jim was moderately successful at generalization with a trial distance of 8 m. Jim
demonstrated skill maintenance for 100% of the trials, (distance of 12 m). He
demonstrated skill generalization for 50% of the trials, (distance o f 12 m).
Downstrokes per Minute
Downstrokes per minute was another dependent variable that was recorded
Figure 2 is a graphic display of the number of downstrokes per minute, by bike and by
trial. The number of acquisition downstrokes per minute (dpm) on Bike A range from
60-200. There was a sharp increase in dpm during acquisition, with a drop to 126 dpm for
the generalization probe. Bike B acquisition elicited a rather sharp increase in dpm (from
70-200dpm). During the generalization probe, there was a decrease to 140 dpm. On Bike
C, Jim demonstrated a sharp increase in dpm (from 30-180), followed by a decrease from
180-105 dpm. This decrease followed instructor feedback asking Jim to slow down. Jim
was intentionally speeding up as he approached the wall at the end of the gym and the
instructor felt that it was necessary to intervene to ensure his safety. During the Bike C
generalization probe, Jim rode at 113 dpm. During acquisition on Bike D, he exhibited a
range o f44-155 dpm. Jim again demonstrated a rapidly increasingly data
path, followed by a sharp decrease when reminded to slow down. The Bike D
generalization probe elicited 40 dpm. On Bike E, Jim’s initial probe was 30 dpm. This
64
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
DOWNSTROKES PER MINUTE •Z' A Figure 2. D ow nstrokes p er M inute, by bike and tria l (P articipant #1) articipant (P l tria and bike by inute, M er p nstrokes ow D 2. Figure * * * * * * * TRIALS 65 * S 0 GENERALIZATION 0 • PCACriCE * FEEDBACK * FEEDBACK PCACriCE • MAINTENANCE e d o k was followed by an increase as well as a mildly variable data path during acquisition,
(range o f 69-84 dpm). During maintenance, be demonstrated a mildly variable data path
(range o f69-96 dpm). During generalization, the pattern was also mildly variable, (range
o f75-96 dpm).
Head Position
Figure 3 is a graphic display of upright head position (uhp) data based on the
percentage o f intervals that the participant’s head was in an upright position On Bike A
acquisition, Jim demonstrated a sharp increase (0 to 50%) in uhp. Dining the Bike A
generalization probe, upright head position was recorded at 33%. On Bike B, Jim
demonstrated 0% uhp throughout acquisition and the generalization probe. On Bike C
acquisition, Jim initially demonstrated a steady data path of 0% uhp, followed by a rapid
increase to 100%. On the Bike C generalization probe, he also displayed 100% uhp. On
Bike D acquisition, he initially demonstrated 0% uhp followed by a rapid increase of
100%. On Bike D generalization probe, a rapid decrease to 0% uhp was observed. On
Bike E acquisition, Jim demonstrated a highly variable data path o f upright head position
(range of 0-100%). During the Bike E maintenance session, upright head position
increased from 0-50%, followed by a decrease and then a consistent pattern of 0%.
During the generalization session, upright head position was highly variable, (range o f 0-
100%).
66
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
% UPRIGHT HEAD POSITION Figure 3. Percent U pright Head Position* by bike and tria l (P articipant #1) articipant (P l tria and bike by Position* Head pright U Percent 3. Figure tees- 67 TRIALS m E s o a r O A CEMEKAUZA.TWN Q • PRACTICE * FEEDBACK * PRACTICE • ntenance c n a n e t in a m A Summary
Jim successfully acquired the skill o f riding a conventional bicycle after 29 trials,
in o ik session. He maintained this skill at 100%. He was able to generalize this skill 50%
of the time. He demonstrated a mean o f 85 dpm and 10% upright head position during
maintenance. During the generalization session, he demonstrated a mean o f 82 dpm and
25% uhp.
Participant 2
D istance and T rials
Billy rode the 16 in (40.64 cm) bicycles and acquired the skill of riding a
conventional bicycle in two sessions (50 trials total). Figure 4 is a graphic display of
Billy’s acquisition, maintenance, and generalization of conventional cycling skills across
Bikes A-E. During the pretest tnals, Billy rode: Bike A, a distance of 12 m; Bike B, a
distance of 0 m; Bike C, a distance of 9 m; Bike D, a distance of 1 m and Bike E, a
distance of 3 m. Billy immediately met criterion levels on Bikes A, B and C. hi addition,
he was also able to generalize this skill for a distance o f 12 m on Bikes A, B and C. Up to
this point, bicycle probes for Bike D ranged horn 0 to I m in distance. The data path for
Bike D was extremely variable, ranging from 0 to 12 m. After 17 trials, Billy successfully
met criterion level (12 m) m 3 out o f 5 trials. He was also able to generalize this skill at a
distance o f 12 m on Bike D. Up to this point, bicycle probes o f Bike E ranged from 0-12
m. Baseline measures for Bike E were extremely variable, ranging from 4-12 m. After 10
trials, Billy successfully met criterion levels o f 3 out o f 5 trials at 12 m. He was also able
to generalize this skill at a distance o f 12 m on Bike E. During the maintenance and
68
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
DISTANCE/METERS Figure 4. D istance traveled in m eters, by bike, tria l, session ( | ) (P articipant #2) articipant (P ) | ( session l, tria bike, by eters, m in traveled istance D 4. Figure *T®|—0 B, 5 |~ (J |~ 5 B, 1 •r > • . a i ® 1 1 1 l \ t 1 ------! * i L i I#’ B ~ si ------. ------° T r TR/ACS 4HMMKMMX Q(Mwmg>now Y^TVY ------* B C A generalization session, Billy demonstrated maintenance o f the skill doting 20% o f the
time, at 12 m. He demonstrated generalization o fthe skill during 80% o f the
generalization trials, at 12 m.
Downstrokes per Minute
Figure 5 is a graphic display ofthe number o f downstrokes per minute, by bike
and by triaL The number o f acquisition downstrokes per minute (djm ) on Bike A range
from 49-92. Billy demonstrated a gradual increase in dpm during acquisition. The
generalization probe was recorded at IB dpm. On Bike B, the data path initially revealed
a rapid increase, followed by a gradual increase in downstrokes per minute. The range
was 30-120 dpm on Bike B. The generalization probe was recorded at 133 dpm. On Bike
C, the range was 64-106 dpm during acquisition. Billy exhibited a gradual increase in
dpm. The generalization probe for Bike C was recorded at 113 dpm. On Bike D, the
range was 0-80 dpm during acquisition. Downstrokes per minute were variable during
acquisition. The generalization probe was recorded as 72 dpm on Bike D. On Bike E, the
data path was variable, with a range of 0-86 dpm. The generalization probe was 75 dpm
on Bike E. During Billy's maintenance session, he demonstrated a variable data path,
with a range o f20-90 dpm. During generalization, the data path was variable, with a
range o f30-90 dpm.
Head Position
Figured is a graphic display of head position data based on the percentage of
intervals that Billy's head was in an upright position. On Bike A, Billy demonstrated a
higdily variable data path, with a range of 0-78% during acquisition. Upright head
7 0
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. * PRACTICE* FEEDBACK. 0 PROBE Q oenerauzation MAINTENANCE ------»A
r & fc*o ■? €
Cj r § *5v*
^ - D
■ f t v A A 0
TRt/HS
Figure 5. Downstrokes per Minute, by bike and trial (Participant # 2 )
71
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. • PRACTICE * FEEDBACK 0 PROBE Q GENERALIZATION A MAINTENANCE f r
IV &
o
Figure 6. Percent Upright Head Position, by bike and trial (Participant #2)
72
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. position was 0% for the generalization probe on Bike A. On Bike B, the data path was
extremely variable, with a range from 20-100% uhp. The generalization probe was
recorded at 50%. On Bike C, the data path was extremely variable, with a range of 25-
100% uhp. The generalization probe on Bike C was recorded at 67%. On Bike D, the data
path was extremely variable, with a range of 0-100%. The generalization probe was
recorded as 67% on Bike D. On Bike E, the majority of uhp data points (12 out of 14)
were at 100%. The range on Bike E was 0-100%. The generalization probe was recorded
at 0% uhp. During Billy’s maintenance session, the data path was extremely variable,
with a range o f 0-100%. During the generalization session, the data path was extremely
variable, with a range o f 0-100%.
Summary
Billy successfully acquired the skill of riding a conventional bicycle after a total
o f 50 trials, across two sessions. He maintained this at 20%. He was able to generalize
this skill 80% of the tnne. He demonstrated a mean of 51 dpm and 67% upright head
position during maintenance. During the generalization session, he demonstrated a mean
of 65 dpm and 70% upright head position.
Participant 3
D istance and T rials
Mary rode the 16 in (40.64 cm) bicycles and acquired the skill of riding a
conventional bicycle in four sessions (82 trials total). Figure 7 is a graphic demonstration
ofMary’s acquisition, maintenance, and generalization of conventional cycling skills
across Bikes A-E. During the pretest trials, Mary rode: Bike A, a distance of 12 m; Bike
B, a distance o f 3 m; Bike C, a distance of 12 m; Bike D, a distance of 3 m; and Bike E, a
73 j
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced Figure 7 . D istance traveled in m eters, by bike, tria l, session ( ! ) (Participant #3) (Participant ) ! ( session l, tria bike, by eters, m in traveled istance D . 7 Figure a-|«,— 0 a-|«,— "I
Pi'STAHCe/AiimtS L^r i * » ej- !*-»• » • ■» a-l • ------* i • • * _ • 1 — 1 • —~- - ~ t— t i l ------( 1 1_ ' ' 0 . " W J U w m i n — H ^ b M^ M T B M M C X . i .♦ 1 ------TRIALS 74 ----- * 1 ------T W/“ ------« a A & B c distance of I m. Following the pretest, Mary immediately met criterion levels on Bike A.
She was also able to generalize this skill at a distance of 12 m on Bike A. On Bike B,
Mary had one bike probe at 11 meters. During acquisition, she met criterion after 6 trials.
She was also able to generalize this skill at a distance of 12 m on Bike B. On Bike C,
Mary had two probes, one at 5m and one at 12 m. She immediately met criterion levels
on Bike C in three trials. She was able to generalize this skill at a distance of 8 m on Bike
C. On Bike D, Mary had three probes at 0 m. The data path for Bike D was extremely
variable and increasing. After 40 trials, Mary met criterion levels on Bike D. She was
able to generalize this skill at a distance of 4 m. On Bike E, Mary had seven bike probes
ranging from 0-5 m in distance. Mary met criterion levels during acquisition after 12
trials. The data path was extremely variable. Two generalization probes were recorded at
0 and I m in distance. During the maintenance and generalization session, Mary
demonstrated maintenance o f the skill 70% of the time, at 12 m. Mary demonstrated
generalization of the skill at 1-4 in, on Bike E.
Downstrokes per Minute
Figure 8 is a graphic display of the number of downstrokes per minute, by bike
and by trial. The number of downstrokes per minute on Bike A range from 78-112, with a
variable data path. The generalization probe on Bike A was recorded at 100 dpm. On
Bike B, the data path was extremely variable, with a range o f30-124. The generalization
probe on Bike B was recorded at 96 dpm. On Bike C, the data path was gradually
increasing, with a range o f 58-115 dpm. The generalization probe on Bike C was
recorded at 110 dpm. On Bike D, the data path was variable, with a range of 0-120 dpm.
The generalization probe on Bike D was recorded at 48 dpm. On Bike E, the data path
75
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Figure S. Downstrokes per Minute, by bike and trial (Participant #3)
76
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. over the first half of trials was extremely variable, with a range o f 0-150 dpm. During the
remaining trials, the data path became more stable, with a range o f70-96 dpm. The
generalization probe was recorded at 60 dpm on Bike E. During Mary’s maintenance
session, the data path was stable, with a range o f69-96 dpm. During generalization trials,
the data path was stable, with a range o f60-72 dpm.
Head Position
Figure 9 is a graphic display o f upright head position data based on the percentage
of intervals that the participant’s head was in an upright position. On Bike A, the data
path was extremely variable, with a range o f 0-50%. The generalization probe was
recorded at 60% uhp. On Bike B, the data path was extremely variable, with a range o f 0-
100%. The Bike B generalization probe was recorded at 0% uhp. On Bike C, the data
path was variable (range o f 0-33%) uhp. The generalization probe was recorded at 0%
uhp. On Bike D, the majority (27 out of 28) of data points over the first half of
acquisition, were at 0% uhp. During the second half of Bike D acquisition, the data path
became extremely variable, (range o f 0-100%). The generalization probe for Bike D was
recorded at 100% uhp. On Bike E, the first half of the data path was stable at 0% uhp.
The second half of the data path was extremely variable, with a range of 0-100% uhp.
The generalization probe on Bike E was recorded at 100% uhp. During the maintenance
session, Mary demonstrated an extremely variable data path, with a range of 0-100% uhp.
During the generalization session, Mary exhibited an extremely data path, with a range of
0-100% uhp.
77
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Figure 9. Percent Upright Head Position, by bike and trial (Participant #3)
78
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Summary
Mary successfully acquired the skill of riding a conventional bicycle in five
sessions (82 trials total). She maintained this skill 70% of the time at a distance of 12 m.
She generalized this skill at 1 to 4 m. Mary demonstrated a mean of 88 dpm and 20%
upright head position during maintenance. During the generalization session, she
demonstrated a mean o f 63 dpm and 63% upright head position.
Participant4
D istance and Trials
Jack rode the 20 in (50.8 cm) bicycles and acquired the skill of riding a
conventional bicycle in 4 sessions (156 trials total). Figure 10 is a graphic display of
Jack’s acquisition, maintenance, and generalization o f conventional cycling skills across
Bikes A-E. During the pretest trials, Jack rode: Bike A, a distance of 12 m; Bike B, a
distance of 0 m; Bike C, a distance o f 0 m; Bike D, a distance of 0 m; and Bike E, a
distance of 0 m. Jack immediately met criterion levels of 3 out of 5 trials at 12 m on Bike
A. He was also able to generalize this skill at a distance of 12 m. Jack rode 0 m on Bike B
during a bicycle probe. Dining acquisition, the data path was rapidly increasing He met
criterion levels after 6 trials. The generalization probe elicited a distance of 4 m. On Bike
C, two probes elicited distances o f 0 and 1 m respectively. During acquisition, he was
able to meet criterion levels following 6 trials. The generalization probe elicited a 1 m
distance. On Bike D, three probes elicited distances ranging from 0-1 m. Throughout the
first 77 intervention trials (two-thirds of all intervention trials), Jack demonstrated a
variable data path, (range of 0-7 m in distance). For the remaining 27 intervention trials,
the data path became extremely variable, (range of 2-12 m). During tins period, Jack met
7 9
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Figure 10. Distance traveled in meters, by bike, tria
I 80 i
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8
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stance traveled in meters, fay bike, trial, session (I) (Participant #4)
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. criterion levels on Bike D. On Bike E, Jack experienced 11 probes, with a range of 0-5 m.
Daring acquisition, Jack met criterion levels on Bike E after 15 trials. The data path was
extremely variable, with a range of 3-12 m. During the maintenance and generalization
sessions, Jack demonstrated maintenance o fthe skill daring 90% o fthe trials, at 12 d e l He
demonstrated generalization o f the skill during 40% of the trials at a distance of 12 m.
Downstrokes per Minute
Figure 11 is a graphic display of the number of downstrokes per minute, by bike
and by triaL The number or downstrokes per minute (dpm) on Bike A increased rapidly,
with a range of46-105. There was a decrease in dpm with the generalization probe,
which elicited a cadence o f 86 dpm. On Bike B, there was a rapid increase in the data
path, with a range of 0-105 dpm. The generalization probe was recorded at 68 dpm. On
Bike C, the date path was variable, with a range of 0-60 dpm. The generalization probe
was recorded at 45 dpm. On Bike D, the data path was variable, with a range of 0-80
dpm. The generalization probe was recorded at 60 dpm. On Bike E, the data path
variable with a range of 0-60 dpm. During Jack’s maintenance session, he demonstrated a
steady data path, with a range o f53-70 dpm. During generalization, the data path was
steady, with a range o f40-70 dpm.
Head Position
figure 12 is a graphic display of head position data based on the percentage of
intervals that the participant’s head was in an upright position. On Bike A, the data path
was extremely variable, with a range o f33-100%. The generalization probe was recorded
at 75% uhp. On Bike B, the data path was extremely variable, with a range of 0-100%.
During the generalization probe, uhp was recorded at 100%. On Bike C, the data path
s i
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
Pew»tncc»*< ftH aimvTV i U ' S Figure 11. D ow nstrokes p er M inute, by bike and tria l (P articipant #4) articipant (P l tria and bike by inute, M er p nstrokes ow D 11. Figure 82 TPtALC* tuamuKS £ 0 B Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
% UPfi\iXT «£/*0 A * /7 * W IV TV r i ■ V | Figure 12. Percent U pright H ead P osition, by bike and tria l (P articipant #4) articipant (P l tria and bike by osition, P ead H pright U Percent 12. Figure 1 IV BBH^p ^ H B tB y W H W S M P T 85 QcoOTMrtoncw e ------"V " •
...... 0 E 6 c 1) A was extremely variable, with a range of 0-100%. The generalization probe was recorded
at 100% uhp. On Bike D, Jack demonstrated 100% uhp during a majority o f the trials (94
of 107), with a range o f 0-100%. The generalization probe was recorded at 100% uhp. On
Bike E, Jack demonstrated 100% uhp during a majority o f the trials (22 o f 28), with a
range o f 0-100%. During Jack's maintenance session, a stable data path o f 100% uhp in 9
out of 10 trials was observed. One trial was observed at 0%. During the generalization
session, uhp was stable at 100% in 13 o f IS trials. Two trials were observed at 50% uhp.
Summary
Jack successfully acquired the skill of riding a conventional bicycle in four
sessions (156 total trials). He maintained this skill 90% o f the time at a distance of 12 m.
He was able to generalize this skill 40% of the time at a distance of 12 m. He
demonstrated a mean of 60 dpm and 90% upright head position during maintenance.
During the generalization session, he demonstrated a mean o f 53 dpm and 87% upright
head position.
Participant 5
D istance and T rials
Jeremy initially rode the 20 in (50.8 cm) bikes. He easily met criterion on the 20
in Bike A, but experienced difficulty with the 20 in version o f Bike B. At this point, he
switched to the 16 in (40.6^ cm) bicycles and remained on the 16 in bicycles throu^iout
the study. Jeremy acquired the skill of riding a conventional bike in four sessions (195
total trials). Figure 13 is a graphic display of Jeremy's acquisition, maintenance, and
generalization of conventional cycling skills across Bikes A-E. During the pretest trials,
Jeremy rode: Bike A, a distance o f 12 m; Bike B, a distance o f I m, Bike C, a distance of
84
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I_____
Figure 13. Distance traveled in meters
85
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. c
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.AWA f W e 7*vtS stance traveled in meters, by bike; trial, session (1) (Participant #5)
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. I m; Bike D, a distance of I m and Bike E, a distance of I m. Jeremy immediately met
criterion levels (3 out o f5 trials at 12 m) on Bike A. He was able to generalize this skill
at a distance o f 12 m. On Bike B, he had one probe at a distance o f 1 m. After 32 trials
Jeremy experienced very limited success, (distance range of 0-5 m). At this point, a
decision was made to put Jeremy on the 16 in (40.64 cm) bike. After 13 trials on the
smaller bike, Jeremy met criterion levels. He was able to generalize this skill at a distance
of 12 m. On Bike C, Jeremy experienced two probes at 0 m (20 in bike) and I m (16 in
bike). On Bike C, Jeremy immediately met criterion IeveL He was able to generalize this
skill at a distance of 12 m. On Bike D, Jeremy had three probes. The first probe was on a
20 in bike at 1 m, and the next two probes were on the 16 in bike, both at I m. During the
first 35 trials (first third) of intervention, Jeremy demonstrated a variable data path in the
range of 0-5 m. Over the remaining 70 trials (last two-thirds) of intervention Jeremy
demonstrated an extremely variable data path, with a range of 0-12 m. During this time,
he did not reach the criterion level o f 3 out of 5 trials at 12 m. Rather, it was during a
probe of Bike E, that he met criterion levels on Bike E, effectively skipping Bike D.
Jeremy experience a total of 27 probes o f Bike E throughout the study. The first 23
probes were in the range of 1-8 m. In the final four consecutive probes, Jeremy rode Bike
E a distance o f 12 m each time. During the generalization pro be o f Bike E, he rode a
distance of 4 m. During the maintenance and generalization session, Jeremy
demonstrated maintenance of the skill during 40% of the time at 12 m. He demonstrated
generalization ofthe skill in the range o f 1-4 m.
86
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Downstrokes per Minute
Figure 14 is a graphic display of the number o f downstrokes per minute, by bike
and by triaL The number o f downstrokes per minute (dpm) on Bike A ranged from 33-46.
The generalization probe was recorded at 34 dpm for Bike A On Bike B, Jeremy
demonstrated a variable data path, with a range of 0-62. The generalization probe was
recorded at 66 dpm on Bike B. On Bike C, the data path was rapidly increasing, with a
range o f 0-73 dpm. The generalization probe was recorded at 66 dpm on Bike C. On Bike
D, Jeremy demonstrated an extremely variable data path, with a range of 0-180 dpm. On
Bike E, the data path was initially extremely variable and increasing, this was followed
by a variable data path. The range for Bike E was 0-150 dpm. The generalization probe
elicited a cadence of 150 dpm on Bike E. During the maintenance session, the data path
was extremely variable, with a range of60-140 dpm. During the generalization session,
the pattern was extremely variable, with a range o f60-120 dpm.
Head Position
Figure 15 is a graphic display of head position data, based on the percentage of
intervals that the participant’s head was in an upright position. On Bike A, Jeremy
demonstrated an extremely variable data path (range o f56-100%). The generalization
probe elicited 67% uhp on Bike A On Bike B, the data path was extremely variable,
with a range o f 0-100%. The generalization probe elicited 71% uhp on Bike B. On Bike
C, the data path was extremely variable. The generalization probe elicited 60% uhp.
On Bike D, the data path was extremely variable across the first 72 trials (first two-thirds)
of acquisition, (range of 0-100%). The final 36 Bike D acquisition trials (last third) were
variable, with 32 trials at 100% and 4 trials at 0% uhp. On Bike E, the majority of the
87
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. **-1 * rucna * nnaMX
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Figure 14. Downstrokes per Minute, by bike and trial (Participant #5)
88
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. #nucm *ntnua n 0NflN BaBWutfrmw A
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Figure 15. Percent Upright Head Position, by bike and trial (Participant #5)
89
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. first half of the trials were at 0% uhp (15 of 17). During second half of trials were stable
at 100% for 11 consecutive trials. The generalization probe was elicited 100% uhp.
During the maintenance session, Jeremy demonstrated a variable data path, with a range
of 0-100%. During the generalization session, the data path was stable, with 13 out of 15
trials at 100%.
Summary
Jeremy successfully acquired the skill o f riding a conventional bicycle in four
sessions (195 total trials). He maintained this skill 29% o f the time at 12 m. He was able
to generalize this skill for a distance of 1-4 m_ Jeremy demonstrated a mean of 109 dpm
and 83% upright head position during maintenance. During the generalization session, he
demonstrated a mean of 96 dpm and 87% upright head position.
Participant 6
Distance and Trials
Bob rode the 20 in (50.8 cm) bicycles and acquired the skill of riding a
conventional bicycle in 6 sessions (162 total trials). Figure 16 is a graphic display o f
Bob’s acquisition, maintenance, and generalization o f conventional cycling skills across
Bikes A-E. During the pretest trials, Bob rode: Bike A, a distance of 12 m; Bike B, a
distanceof I m; Bike C, a distance of I m; Bike D, a distance o f 0 m; Bike E, a distance
o f 0 m. Bob immediately met the criterion levels on Bike A. He was also able to
generalize this skill at a distance of 12 m on Bike A. During acquisition, Bob
demonstrated an extremely variable data path. He meet criterion levels after 26 trials on
Bike B. The generalization probe was recorded at 4 m. On Bike C, Bob had one probe at
0 m. During acquisition, Bob had a higher level o f responding, but with more variability,
90
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Figure 16. Distance tra\
91
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. *ruao>«ciDucx.
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I fi. Distance traveled in meters, by bike, trial, session ( |) (Participant #6)
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. (range o f 5-12 m). Bob met criterion levels after S trials. The generalization probe elicited
a distance of 4 m. On Bike D, Bob had two probes at 1 and 2 m_ During acquisition, Bob
demonstrated an extremely variable data path. He met criterion levels after 82 trials on
Bike D. The generalization probe elicited a distance of 1 m. Bob experienced 11 probes
on Bike E, with a range of 0-6 m. The data path during acquisition was extremely
variable, with a range of 4-12 m. Bob met criterion levels on Bike E after 15 trials. The
generalization probe on Bike E elicited a distance of I m. During the maintenance and
generalization session, Bob demonstrated maintenance of the skill during 20% of the
trials at 12 m. The data path during maintenance was extremely variable, with a range of
2-12 m. He demonstrated generalization o f the skill in the range o f 1-4 m after five trials.
He refused to complete the remaining generalization trials.
Downstrokes per minute
Figure 17 is a graphic display o f the number of downstrokes per minute, by bike
and by trial. The number of downstrokes per minute (dpm) on Bike A ranged from 60-80.
The generalization probe was measured at 55 dpm. On Bike B, the data path was
extremely variable, with a range of 0-120 dpm. The generalization probe elicited a
cadence o f 60 dpm on Bike B. On Bike C, the data path was initially extremely variable,
with a range of 12-120 dpm. In the remaining acquisition trials, the data path was stable
and gradually increasing, with a range o f28-75 dpm. Bob demonstrated a decrease
during the generalization probe with 35 dpm. On Bike D, the data path was variable, with
a range o f 0-96 dpm. The generalization probe elicited a cadence of 30 dpm. On Bike E,
the data path was variable, with a range of 0-90 dpm. The generalization probe elicited a
92
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. JB • RACm* fBDtAOC OfMSK
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Figure 17. Downstrokes per Minute, by bike and trial (Participant #6)
95
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. cadence o f 60 dpm. During the maintenance session, Bob demonstrated a variable data
path, (range o f60-90 dpm) on BikeE. During generalization, the data path was steady a t
60 dpm.
Head Position
Figure IS is a graphic demonstration of head position data based on the
percentage o f intervals that the participant's head was in an upright position. On Bike A,
Bob demonstrated an extremely variable data path, with a range o f20-60% uhp. The
generalization probe elicited 20% uhp. On Bike B, Bob demonstrated an initially low and
stable data path at 0% uhp, with one trial of 50%. This was followed by an extremely
variable pattern ranging from 0-100%. The final third ofBob’s trials on Bike B returned
to a low and stable data path o f 0% uhp. The generalization probe elicited 0% uhp.
Upright head position on Bike C was extremely variable. On Bike D, Bob initially
demonstrated a low and stable data path o f 0% uhp. This was followed by an extremely
variable data path (range o f 0-100%) uhp on Bike D. The generalization probe elicited
0% uhp. On Bike E, Bob initially demonstrated a low and stable data path of 0% uhp.
This was followed by an extremely variable data path ranging from 0-100%. The Bike E
generalization probe elicited 0% uhp. During the maintenance session, Bob demonstrated
a low and stable data path at 0% uhp. During generalization, upright head position was
extremely variable with a range o f 0-100%.
Summary
Bob successfully acquired the skill of riding a conventional bicycle in 6 sessions
(162 total trials). He maintained this skill 50% o f the time at 12 m. He was able to
94
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Figure IS. Percent Upright Head Position, by bike and trial (Participant #6)
95
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. generalize this skill in the range o f 1-4 m. He demonstrated a mean o f 73 dpm and 0%
upright head position during maintenance. During the generalization session, he
demonstrated a mean o f 60 dpm and 20% upright head position.
Participant?
D istance and T rials
Pete rode the 20 in (50.8 cm) bicycles and acquired the skill of riding a
conventional bicycle in 6 sessions (273 total trials). Figure 19 is a graphic demonstration
ofPete’s acquisition, maintenance, and generalization of conventional cycling skills
across Bikes A-E. During the pretest trials, Pete rode: Bike A, a distance of 12 m; Bike B,
a distance of I m; Bike C, a distance o f I m; Bike D, a distance o f 0 m; and Bike E, a
distance of 0 m. Following the pretest, Pete immediately met criterion levels on Bike A.
He was also able to generalize this skill at a distance of 12 m. On Bike B, there was one
probe for a distance of I tn. During the first 33 trials of intervention, the data path was
variable, with a range of 0-3 m. It became evident, that Pete was not making any progress
on Bike B. At this point, a roller change was made on Bike B. The #7 roller was replaced
by the #5 roller. Pete immediately met criterion levels on Bike B with the #5 roller and
was able to generalize this skill at 4 m. The #7 roller was then reinserted onto Bike B.
Pete then demonstrated an extremely variable data path with a range o f 0-12 m. He met
criterion levels on Bike B after 62 trials with the #7 roller in place. He was able to
generalize this skill at a distance o f 4 m. Pete experienced 5 probes on Bike C (2-12 m).
He immediately met criterion levels on Bike C. He was able to generalize this skill at a
distance of 12 m on Bike C. Pete experienced 6 probes on Bike D (range of 1-5 m).
During acquisition, the data path was extremely variable. Pete met criterion levels after
9 6
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. n A n ^ tA a /—^ A/S=
Figure 19. Distance traveled in m
97
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. £
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istance traveled in meters, by bike, trial, session ( | ) (Participant #7)
t I . Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 116 trials on Bike D. He was able to generalize this skill at a distance of 4 m on Bike D.
On Bike E, Pete experienced 26 probes, with a range o f 0-12 m. Pete immediately met
criterion levels on Bike E. The generalization probe elicited a distance o f 1 m. Pete
demonstrated maintenance o f the skill 43 % o f the time at a distance o f 12 m. He
demonstrated generalization in the range of 1-8 m on Bike E.
Downstrokes per Minute
Figure 20 is a graphic display of the number of downstrokes per minute, by bike
and by triaL The number of downstrokes per minute on Bike A, range from 57-84, with a
gradually increasing data path. The generalization probe elicited a cadence of 67 dpm. On
Bike B, the data path was initially extremely variable, (range o f 0-180 dpm). At this
point, a roller change from #7 to #5 was made. On Bike B (roller #5) the data path was
gradually increasing (range o f66-94 dpm). Roller #7 was reinserted and the data path
was variable, (range of60-140 dpm). The generalization probe elicited a cadence of 110
dpm. On Bike C, the data path was variable and gradually increasing, (range of 30-100
dpm). The generalization probe elicited a cadence o f 100 dpm. On Bike D, the data path
was initially variable, (range o f 0-120 dpm) across the first 49 trials. The data path for the
remaining 40 trials was fairly stable, (range o f45-80 dpm). The generalization probe
elicited a cadence o f 60 dpm on Bike D. On Bike E, the data path was variable, (range of
0-90 dpm). The Bike E generalization probe elicited a cadence o f 60 dpm. During Pete’s
maintenance session, he demonstrated a variable data path, (range o f38-70 dpm). During
the generalization session, the datapath was variable, (range o f40-90 dpm).
98
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
fKM /♦>***-'rs Figure 20. D ow nstrokes per M inute, by b ike and tria l (Participant #7) (Participant l tria and ike b by inute, M per nstrokes ow D 20. Figure nruK-s gffllBBtfpHBB 99 Head Position
Figure 21 is a graphic display o f head position data, based on the percentage of
intervals that the participant’s head was in an upright head position. On Bike A, Pete
demonstrated a stable data path of 0% uhp. The generalization probe elicited 67% uhp.
On Bike B, the data path was initially low and extremely variable, (range of 0-100%).
The majority of trials (29 out o f 36), w oe at 0% uhp. The rollers were then changed on
Bike B, horn a #7 to a #5. At this point, the data path was rapidly decreasing, with a
range of 0-100% uhp. The #7 roller was reinserted, and the data path became extremely
variable, (range o f 0-100%). The generalization probe elicited 100% uhp. On Bike C, the
data path was initially steady at 0% uhp, followed by extreme variability, (range ofO-
100%). The generalization probe elicited 50% uhp. On Bike D, the data path was
extremely variable (range of 0-100%). The majority of data points (35 out of 46) were at
100% uhp, in the final half of trials on Bike D. The generalization probe elicited 100%
uhp. On Bike E, the data path was extremely variable, (range of 0-100%). The
generalization probe elicited 100% uhp. During Pete's maintenance session, the data path
was extremely variable (range o f 0-100%) uhp. During the generalization session, the
data path was extremely variable (range of 0-100%) uhp.
Summary
Pete successfully acquired the skill of riding a conventional bicycle in six sessions
(273 total trials). He maintained this skill 43% of the time at a distance o f 12 m. He was
able to generalize this skill with a range of 1-8 m in distance. He demonstrated a mean of
56 dpmand47% upright head position during maintenance During the generalization
session, he demonstrated a mean of 58 dpm and 64% upright head position.
too
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. m * n w n > m u x - Q______t 4. MAOrmiAMCK a-
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Figure 21. Percent Uprigbt Head Position, by bike and trial (Participant #7)
101
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Participants
Distance and Trials
Danny rode the 20 in bicycles and acquired the skill of riding a conventional
bicycle in 7 sessions (230 total trials). He did experience 5 trials on the 16 in version of
Bike B. Figure 22 is a graphic demonstration ofDanny’s acquisition, maintenance, and
generalization of conventional cycling skills across Bikes A-E. During the pretest trials,
Danny rode: Bike A, a distance of4m ; Bike B, a distance of 1 m; Bike C, a distance o f 0
m; Bike D, a distance of 1 m; and Bike E, a distance of 1 m. Following the pretest, Danny
met criterion levels on Bike A after a total of 5 trials. The generalization probe elicited a
distance of 1 m. During acquisition demonstrated a steady data path at 0 m. At this point,
the 16 in bicycle was utilized. After 5 trials on the 16 in Bike B, the data path remained
steady at 0 m. The 20 in bicycle was reintroduced and over the next 13 trials, Danny
demonstrated a steady data path (range o f 0-1 m). It was determined that in order for
Danny to experience some degree o f success, the rollers would need to be changed. At
this point, the #7 roller was replaced by the #5 roller. The data path became extremely
variable, and after 20 trials Danny met criterion levels on Bike B with the #5 roller. He
was able to generalize this skill at a distance of 12 m. The #7 roller was reinserted on
B ike B a t this point Danny again demonstrated an extremely variable data path. Criterion
levels were met after 63 trials on Bike B with the original #7 roller in place. The
generalization probe elicited a distance of I m. Danny experienced three bicycle probes
on Bike C, each probe was recorded at a distance o f 1 m. Danny immediately met
criterion levels on Bike C. The (fata path was extremely variable. The Bike C
102
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ' A
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Figure 22. Distance traveled in meters,
103
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v w w \ f * 1 t- I <1 ---- * ------i t ___ w
n w w 1------.s
,WI • *• 1 Y*. ptlHi
i i stance traveled in meters, by bike, trial, session ( |) (Participant #8)
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. generalization probe elicited a distance o f 8 m. Danny experience four probes on Bike D
(range o f 0-1 m in distance). Dining acquisition, the data path was initially extremely
variable at low levels, followed by extreme variability at higher levels. Danny met
criterion levels on Bike D after 68 trials. The Bike D generalization probe elicited a
distance o f I meter. Danny experienced 10 probes on Bike E, (range o f 12 m in distance).
During acquisition, data path was extremely variable across 10 trials. He met criterion
during this time. The Bike E generalization probe elicited a distance o f4 m. Danny
demonstrated maintenance of the skill during 45% o f the time at 12 m. He demonstrated
generalization o f the skill in a range of 0-8 m.
Downstrokes per Minute
Figure 23 is a graphic display of the number of downstrokes per minute, by bike
and by trial. The number of downstrokes per minute on Bike A, ranged from 5-47, with a
gradually increasing data path. The generalization probe elicited a cadence of 47 dpm. On
Bike B, the data path was initially extremely variable (range of 0-120 dpm). After the
first 23 trials, roller #7 was replaced by roller #5. The data path with Bike B (roller #5)
was extremely variable (range of 0-120 dpm). After 21 trials, criterion levels were m et
Roller #5 was replaced by the original roller #7. The data path with Bike B (roller #7)
was extremely variable (range o f40-180 dpm). The Bike B generalization probe elicited
a cadence of 120 dpm. On Bike C, the data path was initially variable and gradually
increasing, this was followed by extreme variability. Downstrokes per minute were in the
range o f20-150 on Bike C. The generalization probe elicited a cadence of 87 dpm.
On Bike D, the data path was variable (range of 0-90 dpm). The generalization probe
elicited a cadence o f 60 dpm. On Bike E, the (fata path was variable (range o f0-70 dpm).
104
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3 1*1 $ -
l^pjK r^rV^iBV 181 TKlALS.
Figure 23. Downstrokes per Minute, by bike and trial (Participant #8)
105
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The generalization probe elicited a cadence o f 30 dpm. During Danny7 s maintenance
session, he demonstrated a variable data path (range o f20-80 dpm). During
generalization, the data path was variable, with a range o f30-60 dpm.
Head Position
Figure 24 is a graphic display of head position data based on the percentage of
intervals that the participant head was in an upright position. On Bike A, Danny
demonstrated an extremely variable data path, (range o f 0-50%) uhp. The generalization
probe elicited 0% uhp. Danny performed a total o f six trials on Bike A during acquisition.
On Bike B, Danny initially demonstrated a low level o f upright head position. The first
20 out o f 23 trials were recorded at 0% uhp (range 0-100%). Following this, a ro ller was
change from #7 to #5 was made. During this period, the data path was extremely variable
(range of 0-100%) uhp. The roller was then switched back to a #7, and the data path
remained extremely variable (range o f 0-100%) uhp. Fifteen of the final 18 trials were
recorded at 100% uhp. The generalization probe elicited 100% uhp on Bike B. On Bike
C, the data path was initially low, with 11 out o f 12 trials at 0% uhp. This was followed
by an extremely variable data path, with the majority of trials at 100% uhp (51 out of 61).
The range on Bike D was 0-100% uhp. The generalization probe elicited 100% uhp. On
Bike E, the data path was extremely variable (range o f 0-100%). The majority o f trials
were at 100% uhp (15 out o f 22). The generalization probe elicited 0% uhp. During
Danny’s maintenance session, the data path was extremely variable (range o f 0-100%)
uhp. The majority (9 out o f 11) of trials were at 100%. During the generalization session,
the data path was extremely variable (range o f0-100%). The majority (7 out o f 10) of
trials were at 0% uhp.
106
hL Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. without prohibited reproduction Further owner. copyright the of permission with Reproduced
yt UfWAfT rt>Si npA) Figure 24. Percent U pright Head Position, by bik e and tria l (Participant #8) (Participant l tria and e bik by Position, Head pright U Percent 24. Figure A 107 t j m lw A O M O a g Q - Summary
D anny successfully acquired the skill of riding a conventional bicycle in seven
session (230 total trials). He maintained this skill 45% of the time at a distance of 12 del
He was able to generalize this skill with a range o f 0-8 m distance. He demonstrated a
mean of 57 dpm and 81% upright head position during maintenance. Dining the
generalization session, he demonstrated a mean of 51 dpm and 30% upright head
position.
Participant 9
D istance and T rials
Erin rode the 20 in bicycles and acquired the skill of riding a conventional bicycle
in seven sessions (381 total trials). Figure 25 is a graphic demonstration o f Erin’s
acquisition, maintenance, and generalization of conventional cycling skills across Bikes
A -E During the pretest trials, Erin rode: Bike A, a distance of 12 m; Bike B, a distance of
0 m; Bike C, a distance o f 3 m; Bike D, a distance of 0 m; Bike E, a distance of 0 m.
Following the pretest, Erin immediately met criterion levels on Bike A. The
generalization probe elicited a distance of 4 m. Erin experienced one probe on Bike B at
9 m. Erin immediately met criterion levels on Bike B. The generalization probe elicited a
/Kgtamv* o f 12 m. Erin experienced two probes on Bike C, both at a distance o f 12 m. On
Bike C, she immediately met criterion level. The generalization probe elicited a distance
of 12 m. Erin experienced three probes on Bike D, with a range of 0-1 m. During the first
168 tn>k (first two-thirds) o f intervention, the data path was variable, (range o f 0-7 m).
During the remaining 108 trials of intervention, the data path became increasingly
variable, (range o f 0-12 m in distance). The Bike D generalization probe elicited a
108
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Figure 25. Distance traveled in
* f*»
109
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i IK. ' - • -** - *. - ' " •; ' ' * '• v l U L n e
mce trav eled in meters, by bike, trial, session (j) (Participant #9)
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. distance of 1 m. Erin experienced 56 probes o f Bike E, (range o f 0-5 m). Daring
acquisition, the data path was extremely variable (range o f 0-12 m). After 29 trials, Erin
met criterion levels on Bike E. The generalization probe elicited a distance of 1 m.
D uring th e maintenance and generalization session, Erin demonstrated maintenance of
the skill 7% of the time at 12 m. She demonstrated generalization of the skill with a range
o f 1-4 m.
Downstrokes per Minute
Figure 26 is a graphic display of the number o f downstrokes per minute, by bike
and by trial. The number of downstrokes per minute (dpm) on Bike A ranged from 126-
150. The generalization probe elicited a cadence of 120 dpm. On Bike B, there was a
rapid increase in downstrokes per minute (range o f60-147). The generalization probe
elicited a cadence of 115 dpm. On Bike C, there was a rapid increase in downstrokes per
minute (range of 51-140). The generalization probe elicited a cadence of 105 dpm. On
Bike D, the data path was variable (range o f 0-120 dpm). The generalization probe
elicited a cadence of 30 dpm. On Bike E, the data path was again variable (range of 0-120
dpm). The Bike E generalization probe elicited a cadence o f 60 dpm. During Erin’s
maintenance session, she demonstrated a variable data path (range o f60-120 dpm).
During generalization, the data path was extremely variable (range of 0-120 dpm).
Head Position
Figure 27 is a graphic demonstration of bead position data based on the
percentage of intervals that the participant’s head was in an upright position. On Bike A,
Erin demonstrated variable data path (range of 0-33%) uhp. The generalization probe
elicited 50% uhpt On Bike B, Erin demonstrated a rapid increase in upright head position
n o
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S'
‘V A .A .’/ '
Figure 26. Downstrokes per Mini
111
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 6mm Q rzoL'. kes per Minute, by bike and trial (Participant #9) .,s. .1 '.a-* t’:• •TfikSffll Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ii Miy U: \ mu i i l L i m m r t m i Figure 27. Percent Upright Head Posil 112 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 1 mnmmmmn^pn ight Head Position, by bike and trial (Participant #9) Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. (range of 0-100%). The generalization probe elicited 100% uhp. On Bike C, Erin initially demonstrated a stable data path at 100% uhp. This was followed by a rapid decrease to 50% uhp. The generalization probe elicited 67% nhp. On Bike D, she demonstrated extreme variability in upright head position during the first half o f acquisition. During the majority of the trials in the first half (86 out of 110) upright head position was at 0%. The range was from 0-100%. During the second half the majority of the trials (60 out of 112) upright head position was at 100%. The data path was extremely variable. The Bike D generalization probe elicited 0% uhp. On Bike E, the data path was mostly stable over the first 32 trials, with 30 out of 32 trials at 0% uhp. The range was 0-100% During the remaining trials on Bike E, the data path was extremely variable, however, the majority o f the trials (35 out of 54), she exhibited 100% uhp (range was 0-100%). During Erin’s maintenance session, she demonstrated a highly variable data path (range of 0-100%) uhp. During the generalization session, upright head position was extremely variable (range of 0-100%). Summary Erin successfully acquired the skill of riding a conventional bicycle in seven sessions (381 total trials). She maintained the skill 7% o f the time at 12 m. While Erin did not meet criterion for skill generalization, she did perform generalization trials (range of 1-4 m). Erin demonstrated a mean of 76 dpm and 67% uhp during maintenance During generalization, she demonstrated a mean of 52 dpm and 47% uhp. 113 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Participant 10 Distance and Trials Alien code the 20 in (50.8 cm) bicycles and acquired the skill o f riding a conventional bicycle in seven sessions (227 total trials). Figure 28 is a graphic demonstration o f Allen’s acquisition, maintenance^ and generalization of conventional cycling skills across Bikes A-E. During the pretest trials, Allen rode: Bike A, a distance o f 12 m; Bike B, a distance of I m; Bike C, a distance o f 3 m; Bike D, a distance o f 0 m; and Bike E, a distance of 1 m. Following the pretest, Allen immediately met criterion on Bike A_ The generalization probe on Bike A was recorded at 1 m. On Bike B, Allen experienced one probe, for a distance o f I m. During acquisition, the data path was extremely variable and gradually increasing. He met criterion on Bike B after 39 trials (range of 0-12). The generalization probe elicited a distance of I m. On Bike C, two probes elicited distances of 2 and 4 m. During acquisition, the data path was extremely variable (range of 1-12 m). He met criterion after!9 trials. The generalization probe elicited a distance o f 1 m. On Bike D, Allen experienced two probes at I and 2 m. During acquisition, the data path was initially variable (range o f 2-5 m) this was followed by an extremely variable data path (range o f 2-12 m). Allen met criterion after 66 trials on Bike D. The generalization probe elicited a distance o f I m. On Bike E, Allen experienced 16 probes (range o f 0-10 m). During acquisition, the data path was extremely variable (range o f 2-12 m). Allen met criterion after 38 intervention trials. While Allen did not meet criterion levels for maintenance; he did exhibit partial maintenance with several trials a t 12 m. While Allen did not meet criterion for skill generalization, he (fid perform several trials (range 1-4 m). 114 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Figure 28. Distance traveled in mete IIS Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. »MlS i iveled in meters, by bike, trial, session (I) (Participant #10) Reproducedwith permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Downstrokes per Minute Figure 29 is a graphic display of the number o fdownstrokes per minute, by bike and by trial. The number of downstrokes per minute on Bike A, range from 30-80, with a gradually increasing data path. The generalization probe elicited a cadence of 86 dpm. On Bike B, the data path was initially extremely variable (range of 0-120 dpm), and was followed by a gradually increasing and variable data path (range of 7S-lS7dpm). The generalization probe elicited a cadence of 60 dpm. On Bike C, the data path was extremely variable (range of26-120 dpm). The generalization probe elicited a cadence of 120 dpm. On Bike D, the data path was variable (range o f 0-90 dpm). The generalization probe elicited a cadence o f 60 dpm. On Bike E, the data path was variable (range o f 0- 100 dpm). During Allen’s maintenance session, he demonstrated a somewhat variable data path, (range o f60-80 dpm). During generalization, the data path was somewhat variable (range o f40-60 dpm). Head Position Figure 30 is a graphic display of head position data based on the percentage of intervals that the participant’s head was in an upright position. On Bike A, Allen demonstrated an extremely variable data path (range of 0-80%) uhp. The generalization probe elicited 0% uhp. Allen performed a total of six trials on Bike A during acquisition. On Bike B, Allen demonstrated an extremely variable data path (range o f 0-100%) uhp. The Bike B generalization probe elicited 100% upright head position. Allen performed a total of 53 trials on Bike A during acquisition. On Bike C, Allen demonstrated an extremely variable (fata path (range of 0-100%) uhp. The Bike C generalization probe elicited 100% uhp. Allen performed a total o f 37 trials on Bike C during acquisition. On 116 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. *3 ^ _ _ Braoac ^ 8 QtWaKAUZATMH 0 0“ A Figure 29. Downstrokes per Minute, by bike and trial (Participant #10) 117 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bmai ■ QaMMUZAnON •I\ A. MMOSUMI — L n ------_ A Figure 30. Percent Upright Head Position, by bike and trial (Participant #10) its Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Bike D, Alien demonstrated an extremely variable data path (range of 0-100%) uhp. Initially, the majority o fdata points (24 out o f 30) were recorded at 0% uhp. During the remaining trials, the majority o f data points (22 out o f 38) were at 100% uhp. The Bike D generalization probe elicited 100% uhp. Allen performed a total of 68 trials on Bike D during acquisition. On Bike E, Allen demonstrated an extremely variable data path (range of 0-100%) uhp. Initially, the majority ofdatapom ts( 13 out of 19) were at 0% uhp. Following this, the majority o f data points (30 out o f44) were at 100% uhp. He performed a total of 63 trials on Bike E. During Allen’s maintenance session, the data path was initially extremely variable (range o f 0-100%) uhp. Following this, the data path became more stable, with 11 out o f 12 trials recorded at 100% uhp. During the generalization session, upright head position was initially extremely variable (range of 0- 100%) followed by a stable data path, with 7 out of 7 trials at 100% uhp. Summary Allen successfully acquired the skill of riding a conventional bicycle in 7 sessions (227 total trials). He maintained this skill 47% of the time at 12 m distance. While Allen did not meet criterion for skill generalization, he did perform several trials (range of 1-4 m). He demonstrated a mean of 73 dpm and 87% uhp during maintenance. During the generalization session, he demonstrated a mean of 54 dpm and 60% uhp. Overall Summary ofResuIts Table 6 summarizes the results o f each participant, including number o f trials^ maintenance/generalization, bike size, downstrokes and head position. Table 7 is a summary ofmean elapsed time and range in seconds by bike. 119 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Summary o f Results P a rt T rials: Total M ain. Gen. S ize dpm uhp A B C D E t 4 5 6 7 7 29 YY 20 in 85 10% 2 4 5 6 21 14 50 N Y 16 in 51 67% 3 4 8 6 44 20 82 Y N 16 in 88 20% 4 4 8 9 108 27 156 Y Y 20 in 60 90% 5 4 47 6 no 28 195 N N 16 in 109 83% 6 4 31 16 85 26 162 N N 20 in 73 0% 7 4 101 9 127 32 273 YN 20 in 56 47% 8 6 106 15 76 21 230 Y N 20 in 57 81% 9 4 5 7 271 94 381 NN 20 in 76 67% 10 5 55 36 69 62 227 YN 20 in 73 87% Table 6: Summary of results including participant numbers, trial per bike, total trials, ability to maintain and generalize skill, bike size, mean downstrokes per minute (dpm), and mean percentage o f upright head position (uhp) during maintenance B ike A B ikeB B ikeC B ikeD B ikeE Mean 19.9 sec 8.3 sec 9.8 sec 3.5 sec 3.8 sec Range 8.8-30 sec 4.6-14.2 sec 6.4-14.7 sec 2 .l-6 .5 se c 2.Q-6.9 sec Table 7: Mean elapsed time and range in seconds by bike 120 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Social Validity A four-point Likert scale questionnaire was utilized fo r obtaining the opinions o f participants’ parents, regarding the value of conventional cycling skills (Appendix J). The questionnaire was completed fay 10 of the participants1 mothers. The scale was composed o f the following responses: strongly agree, agree, disagree, ami strongly disagree: Mine of the 10 respondents (90%) strongly agreed and one respondent (10%) agreed with statement one, that a gradual introduction to bicycle-riding is less threatening than the traditional approach of trial and error. Nine of the 10 respondents (90%) strongly agreed and one respondent (10%) agreed with statement two, that their children looked forward to attending cycling sessions. Eight o f the 10 respondents (80%) strongly agreed and two respondents (20%) agreed with statement three, that the use o f adapted bicycles made it possible for their children to ride a conventional bicycle. Six of the 10 respondents (60%) strongly agreed, two agreed (20%), one disagreed (10%) and one strongly disagreed (10%) with statement four, that their children will bicycle ride with friends and/or family. The respondent who strongly disagreed, went on to explain that her child would not attempt to ride the conventional bicycle in an outdoor setting. Four of the 10 respondents (40%) strongly agreed, five respondents (50%) agreed and one respondent (10%) disagreed with statement five, that the ability to ride a conventional bicycle would increase their child1 s level o f physical activity. Eight o f 10 respondents (80%) strongly agreed and two respondents (20%) agreed, with statement six, that the ability to ride a conventional bicycle will increase their child’s feeling o f independence. Six o f 10 respondents (60%) strongly agreed and four respondents (40%) agreed, with statement seven, that learning to ride a conventional bicycle had boosted their child’s self-esteem. 121 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Five of 10 (50%) respondents strongly agreed, four respondents (40%) agreed and one respondent (10%) disagreed, with statement eight, that bicycle riding is a popular recreational activity in my neighborhood Seven of 10 respondents (70%) strongly agreed and three respondents (30%) agreed, with statement ten, that bicycle riding is a lifelong sport/leisure activity. In summary, results of the social validity questionnaire provide strong support for the use o f adapted bicycles in developing conventional cycling skills. This method was perceived as being less threatening than traditional approaches and children anticipated participation in cycling sessions. Strong support was also evident relative to the social, physical, and emotional affects o f learning how to ride a conventional bicycle. Finally, there was strong agreement in terms of the popularity and perception ofbicycling as a lifelong leisure activity. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHAPTERS DISCUSSION This chapter provides 2 discussion of the results of using 2 series o f adapted bicycles on the acquisition, maintenance, and generalization o f conventional cycling skills by children with mild MR The discussion focuses on each of the five research questions, perceived limitations of the study, implications for practice, and suggestions for future research. Finally, a summary of the study is presented. Research Questions Research Question I: Does the use of adapted bicycles by individuals with mild MR affect the acquisition o f conventional cycling skills? Initial probes on Bike E (conventional bike), revealed that none o f the participants in this study were capable of riding a conventional bicycle prior to intervention. The mean distance traveled (hiring initials probes on the conventional bicycle was Im, (range of 0-3 m). O f the 10 participants in this study, all 10 acquired the skill of riding a conventional bicycle at criterion level (3 out of 5 consecutive trials at 12 m). These results represent a 100% success in terms o f acquiring conventional cycling skills. Despite the common knowledge that individuals with MR have difficulty in learning and performing motor tasks, especially tasks that require a temporal response (Kail, 1992; Newell, Wade, & Kelly, 1979), the children in this study experienced success in a short period of time. In addition, findings support the notion that through a progressive change in the task (adapted bicycles), the learner can shift to other modes (e.g. upright head 123 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. position, pedal rate) of functioning (Kelso, 1995). The movement system (learner) spontaneously develops a preferred mode o f coordination to fit the new task (adapted bicycle) constraints (Corbetta & Vereijken, 1999). This was evident as each child progressed from bike to bike. Although there have been no previous empirical studies on the acquisition of conventional cycling skills, the data from this study supports anecdotal evidence from several bicycle camps conducted in Wisconsin and California. Children with a variety of disabilities participated in these bicycle camps and utilized similar adapted bicycles. Overall, the one-week bicycle camps were successful in teaching children how to ride conventional bicycles. However, this is the only empirical study to demonstrate that the use of adapted bicycles has a positive affect on the acquisition o f conventional cycling skills for children with mild MR. cl How many trials to criterion are requiredfor each bicycle during acquisition? On Bike A, the mean trials to criterion was 4.3 (range 4-6). All 10 participants required no positive corrective or positive specific feedback on Bike A. And participants experienced immediate success. This is due to the contour o f the #5 rollers, which make Bike A extremely stable, even when the bike is motionless. On Bike B, the mean trials to criterion was 37.1 (range 5-106). Two participants (Bob- #6 and Allen- #10) required a more than average practice with feedback. Bob (Down syndrome) had difficulty following directions and staying on task. Allen (mild autism/ADD) was very cooperative, however he was generally not focused on the task at hand. He sang songs during most of the trials. It is interesting to note that although most children with MR exhibit developmental motor delays, these seem to be more related to cognitive factors such as 124 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. attention and comprehension rather than to physiological or motor deficits (Krebs, 2000). One participant (Jeremy- #5) experienced initial difficulty on Bike B doe to an inappropriate fit He was 48 in/121.92 cm tall and was attempting to leant on a 20 in/50.8 cm bicycle. Once this was corrected and Jeremy was placed on the 16 in./40.64 cm version of Bike B, he quickly met criterion levels. The remaining two participants (Danny- #8 and Pete- WT) experienced difficulty on Bike B, with the original #7 roller in place. After a period of time, with very limited success, the #7 roller was exchanged for the less contoured (more stable) #5 roller. Both participants experienced success with the £5 roller and quickly met criterion levels. At this point, the #7 roller was reinserted and both participants eventually met criterion levels on Bike B, with instructor intervention. When Danny (developmental delay/cerebral palsy) initially began riding Bike B, he would over-react to any tipping sensation by tightening the muscles in his legs so, that his knees would touch. This reaction would cause the bike to tip. Once he began to participate in the steering to (counter tipping), he began to relax and was less likely to tighten his leg muscles. Postural deviations and cerebral palsy are common in children with MR and can pose problems relative to body mechanics and balance (Krebs, 2000). This was certainly true for Danny. However, taking these factors into consideration and adapting the task by providing him with additional practice on less contoured rollers enabled Danny to experience success and continue to improve. Paul (developmental delay) also had some difficulties with Bike B. He tended to be extremely cautious and reacted to the tipping sensation by taking his feet off of the pedals and placing them on the floor. Again, once he began to participate in the steering, he experienced more success. On Bike C, the mean trials to criterion was 11.6 (range 6-36). Bike C was 125 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. designed to move along with increased forward speed in relation, to pedal cadence. This appeared to be extremely heipfid in assisting participants to maintain balance and meet criterion levels quite rapidly on Bike C. Many o f the participants noticed and commented on the increase in speed. On Bike D, the mean trials to criterion was 91.8 (range 7-271). Only two participants (Joe- #1 and Billy- #2) immediately met criterion levels on Bike D. Joe (Asperger syndrome) has a very high functioning form o f autism. He was extremely attentive and followed directions explicitly. He was very inquisitive and asked a lot of questions about the bikes. Billy (mild Autism) was a risk-taker. He was very relaxed on the bikes from the start. The remaining participants required a additional practice and feedback prior to meeting criterion levels. A few o f the participants seemed to have difficulty with the weight of Bike D. They exhibited this by rocking back and forth as they were riding, in an attempt to gain forward momentum. However, Bike D also proved to be crucial, in that once criterion levels were finally met on this bike, the transition to the conventional bike generally occurred over a short period of time. One participant (Jeremy- #3) effectively skipped Bike D by meeting criterion levels on Bike E during one of the probes. Jeremy was very small and lightweight On Bike E, the mean trials to criterion was 33.1 (range 7-94). Seven of 10 participants immediately met criterion levels on the conventional bicycle. The remaining three participants required very little practice and feedback prior to meeting criterion levels on Bike E. The limited amount of practice and feedback on Bikes A, B, C and E point to the effectiveness o f the adapted bicycle design, in that the bicycles do most o f the teaching From a dynamic systems perspective, the task constraints were amenable to the current abilities of the performer. 126 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. The previous results point to the importance of activity modification. Individuals with MR can participate in challenging sports skills when appropriate modifications are made to enable successful experiences (Krebs, 2000). Modifications were made for the task of cycling by initially reducing the speed of execution and the requirements in terms of reaction time to tipping. Griffin & Keogh (1982) stress the importance of successful experiences in movement situations, because it is these experiences that lead to movement confidence. In this sense, it is essential to know the learner and to provide more simple tasks at first, to provide sufficient practice for mastery and automaticity (Bouffard, 1990). Following the provision o f less demanding tasks, more challenging tasks can be presented. This can be related to the instructional approach o f task analysis, which is commonly utilized with individuals with MR. Since many children with MR have difficulty attending to multiple task cues as typically developing children, breaking the skills down into sequential tasks is a valuable approach (Krebs, 2000). On Bike A. the participant could concentrate on pedaling due to the fact that the bike was so stable. On Bike B, stability became more of an issue, however, the bike was still geared to move forward at a slow speed. On Bike C, the gearing was modified to increase forward speed relative to cadence, however, the stability remained the same. On Bike D, the stability was decreased and the forward speed remained the same. Finally, on Bike E. the participant was ready to tackle the dynamics of a conventional bicycle. The initial successful experiences on the first bikes in the series may have attributed to continued success as the progression became more challenging 127 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. b. What is the overall direction, degree and extent o fvariability o f the trend as defined by the relationship between distance and tried by bike during acquisition? On Bike A, 9 of the 10 participants exhibited a trend that was high and stable, with zero trend. Presumably, this is due to the contour of the #5 toilers, which provide extreme stability, even when the bicycle is motionless. One participant (Danny-#8) demonstrated a trend that was initially tow, but rapidly increased to a high and stable level. Initially, Danny (Cerebral Palsy) exhibited hip and knee flexion with internal rotation. This action was counterproductive to pedaling. On Bike B, 3 of the 10 participants (#’s 1,2 & 9) exhibited a trend that was high and stable, with a zero trend. One participant (#4) demonstrated a trend on Bike B, that was initially low, but rapidly increased to a high and stable level Another participant (#3) demonstrated a trend that was initially extremely variable. However, the variability decreased and performance became more stable. One participant (#6) exhibited a trend that was initially low and variable, followed by extreme variability and increasing levels. One participant (#10) demonstrated extreme variability with a gradually increasing level of performance. One participant (#5) initially exhibited a low and variable trend with the 20 in (50.8 cm) bicycle. After switching to the 16” (40.64 cm) bicycle, the trend rapidly increased to a high and stable leveL Two of the participants (#Ts 7 & 8) required a roller change on Bike B. Both of these participants started out with roller #7 on bike B. Both exhibited trends that were low and variable with zero trend. Upon switching to roller #5 (less contour/more stable at 36.25 arc in) on Bike B, one o f the two participants (Pete-#7) exhibited an immediate increase to a high and stable level. When the #7 (more contour/less stable at 26.35 arc in) roller was reinserted, Pete demonstrated an extremely 128 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. variable trend that gradually increased to a high level. When Danny (#8) experienced a roller change from #7 to #5, he exhibited and extremely variable trend that gradually increased to a high level. When the #7 roller was reinserted, Danny exhibited a highly variable trend that increased to a high level. On Bike C, 6 o f the 10 participants (#’s 1, 2, X 5,7, & 9) immediately exhibited trends that were high and stable with zero trend. The remaining four participants (#Ts 4,6,8, & 10) demonstrated trends that were extremely variable on Bike C. On Bike D, one of the 10 participants (#1) exhibited a trend that was immediately high and stable. Two participants (#’s 2 & 7) demonstrated trends that were extremely variable on Bike D. The remaining seven participants (#Ts 3 ,4 ,5 ,6 ,8 ,9,& 10) demonstrated trends that were initially low and variable, followed by gradually increasing performance levels with extreme variability. On Bike E, one o f the 10 participants (#1) exhibited a trend that was immediately high and stable. One participant (#7) demonstrated a trend that was initially low, followed by a rapid increase to a high level with stability. Seven o f 10 participants (#’s 2, 3 ,4 ,6 ,8 ,9,& 10) exhibited trends with extreme variability. One participant (#5) met criterion level on Bike E during a probe. These probes were stable at a high level on B ikeE . These data concur with descriptions of change as described by dynamic systems theory. For example, Corbetta and Vereijken (1999) describe behavior changes in terms of stability and instability. They note that environmental and/or internal modifications can bring about instability in a movement system. The increasing level o f difficulty from bike to bike and roller to roller represented a change in the task that consequently 129 J I Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. perturbed the movement system towards instability. This was evident in the extreme variability that was observed prior to reaching criterion levels on each bicycle. It is daring these periods of instability that the movement system becomes more flexible; and new modes of functioning are likely to emerge (Corbetta & Vereijken, 1999). Moreover, Kelso et aL, (1993) recognized that unstable patterns are generally considered as predictors of change. Preferred modes of coordination (attractor states) that occur before and after periods o f instability or transition are comparatively stable and resilient to change (Kelso et at., 1993). Traditionally, motor skill acquisition has been described as the process of reducing variability relative to outcome measures. However, in contrast to this Vereijken, van Emmerik, Whiting and Newell (1991) describe the acquisition of coordination as the search for optimal movement strategies. Increased variability prior to the acquisition of a motor skill is supported by Thelen, Corbetta and Spencer (1996), in which the development of reaching in infants was examined. During what is referred to as an "active period”, infants displayed a high level o f variability and enhanced exploration in speed parameters prior to discovering more stable and appropriate speeds for reaching movements. This phenomenon is also evident in research studies involving skill acquisition such as independent walking (Clark, Whitail & Phillips, 1988), a bimanual rhythmic task (Schmidt, Treffiter, Shaw & Turvey, 1992), drawing movemnts (van Emmerick. 1992) and stepping patterns (Vereijken & Thelen, 1997). Therefore, the observation of an increase in the variability of performance is a positive indication that the participant is in the process of exploring increased degrees o f freedom and demonstrating selforganization prior to acquiring and refining new skills. 130 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Visual examination of the graphic display o f data supports the notion that unstable patterns are predictors o f change (Kelso et aL, 1993). Extreme variability in the d ata paths was followed by an increase in performance. The shift from bike to bike represented a change in the task that consequently perturbed the movement system towards instability. c. What is the total number oftrials to criterion fo r conventional bicycle riding during acquisition? The mean trials to criterion for conventional cycling, across Bikes A, B, C, D and E was 179 (range o f29-381). The majority of trials occured on Bike D with a mean of 91.8 trials (51%). Comparatively, the mean number of trials per bike were; Bike A, 4.3 (3%), Bike B, 37.1 (21%), Bike C, 11.6 (7%) and Bike E, 33.1 (18%). The numerous trials on Bike D points to the need for either the creation of an additional bike between Bikes C and D or an alteration in the design o f Bike D. This might assist in filling the gap and providing for a smoother transition from bike to bike. In addition, less instructor intervention would be required From a dynamic systems perspective, if the task dynamics correspond to the existing intrinsic dynamics of a participant, learning the new pattern will be easier (Zanzone & Kelso, 1991). The wide range of total trials (29-381) could be attributed to the personality, disability, and/or behavior of each participant Learner constraints such as attentiveness, flexibility, cooperativeness, and/or motivation could easily attribute to the length o f time required to Ieam a particular skill. Several o f the participants were easily distracted (#’s 2, 3 ,4 ,6 & 10). Again, cognitive factors such as attention and distractibility may be influential in developmental motor delays evident in children with MR (Krebs, 2000). 131 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. One participant (#5) was uncooperative and (fid not follow directions well. When he became frustrated, he would remove his helmet and sit down, refusing to participate. Four participants (#’s 2 ,3 ,5 & 6) could be categorized as being risk-takers. For example, these participants would continue with rapid pedaling despite the fact that they were about to fall. The inclination to take risks was advantageous to learning. It allowed for longer trials and more practice time. They would generally pedal faster and trust that the investigator would catch them if they did fall. In terms o f disability, participant #8 (cerebral palsy) did struggle at times in large part to spasticity in his legs. Three of the participants with autism (#’s 2,4 & 10) were not very focused and were easily distracted. Ail three had a tendency to talk or sing to themselves as they rode the bikes. Perhaps the extreme stability of the adapted bicycles made it possible for participants with an inclination to distraction and inattention to succeed regardless o f their ability to focus on the task. From a dynamic systems perspective, the constraints of the task (stability, slow speed) made allowances for subsystems (such as attentiveness) to gradually fall into place. Newell (1984) supports the notion that movement or skill development such as bicycle riding develops from an interaction among the individual, the task and the environment. However, once participants advanced to less stable variations of the bicycle and the conventional bicycle, some degree of attention became necessary in order to afford safe participation. It may be the case that participants with different ages and behavior characteristics or disabilities might respond differently to the bicycle intervention. 132 i Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Research Question 2: Is the riding o f a conventional bicycle by individuals with mild mortal retardation maintained following the use o fadapted bicycles? Six out of 10 participants (#’s 1,3 , 4 , 7 , 8 & 1 0 ) maintained the skill of conventional cycling at criterion levels. The mean percentage for conventional cycling maintenance was 47% for all participants (range 7-100%). For several participants, a strong attractor well bad not yet developed. Attractors are considered to be preferred modes of behavior (Thelen & Smith, 1994). The attractors for conventional cycling were still in a state of instability. Therefore, they continued to exhibit a highly variable performance. To increase the level o f maintenance by children with mild MR it may be necessary to provide additional practice time on the conventional bicycle, once the skill has been acquired This would result in more stable attractors relative to the skill of cycling. In the present study, as soon as each participant met the 3 out of 5 criterion, practice ceased until the generalization session. A study by Porretta and O’Brien (1991) supports the use of additional practice time relative to increasing retention and transfer of motor skills by children with mild MR. Presenting multiple contexts of related or similar skills can also facilitate retention and transfer o f motor skills (Brooks & McCauley, 1984; Liberty, Haring, White, & Billingsley, 1988). In fact, Salmoni, Schmidt, and W alter (1984) suggest that the acquisition o f motor skills can only be accurately evaluated by examining retention and transfer data. 133 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Research Question 3: Is the riding of a conventional bicycle by individuals with mild MR generalized to a variation of the task? In this study, response generalization was observed. Three o f the 10 participants (#’s 1 ,2 & 4) were able to generalize the skill o f conventional cycling at criterion levels (3 out of 5 consecutive trials at 12 m), through cones set up in a zig-zag pattern. It is interesting to note, that the presence of the cones on the floor were particularly helpful to participant #2 (autism). Although he generally had difficulty focusing on the task, the cones seemed to give him a focal point and his performance greatly improved during generalization trials. Two participants (#’s 7 & 8) were able to generalize the skill up to a distance of 8 m. The remaining five participants (#Ts 3 ,5 , 6,9 & 10) were able to generalize the skill up to a distance of 4 m. Perhaps the low level of generalization performance was due to the limited space in the gym or the spacing of the cones (environmental and task constraints). Moreover, additional practice time on the conventional bicycle may have led to improved generalization. Additionally, more generalization trials could have led to better performance. From a practical standpoint, Bouffard (1990) suggests that retention and transfer of skills should be emphasized in any learning situation. Although generalization probes occurred throughout the acquisition phase, the minimal level of success with generalization in this study points to a need for an increased emphasis in this area, particularly for children with mild MR. In addition to response generalization, practice in natural outdoor environments should also be considered. Bouffard (1990) suggests that individuals with MR be taught in contexts that are as similar as possible to the target task. Consideration o f the natural environment in which the task will eventually be performed should be emphasized (Brown & Campione, 134 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 1986). This is particularly applicable to participant #5, whose mother reported that following the study he refused to ride his bicycle outside. Rather, he wanted to revert to riding his bicycle with training wheels around the neighborhood. This scenario supports the observation by Salmoni, Schmidt, and Waiter (1984) highlighting the need for an examination o f both retention and generalization o f motor skills as part o f a complete evaluation of motor skill acquisition. Research Question 4: Relative to select variables o f dyna m ic systems theory; a. What percentage o f intervals did participants maintain an upright head p o sitio n ? On Bike A, the mean percentage for the upright head position was 35% (range 13- 85%) for all 10 participants. On Bike B, the mean percentage for the upright head position was 40% (range 0-80%) for all 10 participants. On Bike C, the mean percentage for the upright head position was 48% (range 16-83%) for all 10 participants. On Bike D, the mean percentage for the upright head position was 49% (range 14-94%) for all 10 participants. On Bike E, the mean percentage for the upright head position was 49% (range 14-81%) for all ten participants. The interobserver reliability for percentage of upright head position was reported in Table 4. Although and IOA o f 90% or better are generally considered adequate for permanent products, this percentage is arbitrary and must be considered in light o f the complexity and quantity of observations. Interobserver agreement with an average of 75% is considered to be adequate for data collected across intervals o f 5 seconds or less (Cooper, Heron, & Heward, 1987). In this study, the intervals were two seconds in duration. 135 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In order to contextualize the percentage of upright head position and the number of downstrokes per minute, refer to Table 7 fora summary o faverage elapsed tune per trial by bike in addition to the range of elapsed time by bike. The average time per trial on Bike A was 19.9 sec (range of 8.5-30.0), Bike B was 8.3 sec (range of 4.6-14.2), Bike C was 9.8 sec (range o f 6.4-14.7), Bike D was 3.5 sec (range of 2 .1-6.5), and Bike E was 3.8 sec (range of2.0-6.9). Trials on Bike A lasted the longest and trials on Bike D were the shortest in duration. In general, there was a decrease in elapsed time from Bike A to Bike E, with slight variability. Therefore, an upright head percentage of0% or 100% on Bike A would be more significant than an upright head percentage of 100% on Bike E. The same logic applies to do wnstrokes per minute on Bikes A-E. b. What was the member o f downstrokes per minute durmg acquisition? This data is presented based on two different bike sizes. Due to the different circumference of the tires (16 in and 2 0 in), dpm must be compared with the same bike size. On the 16 in (40.64 cm) Bike A, three participants exhibited a mean of 8 8 dpm (range 77-99). On the 20 in (50.8 cm) Bike A, seven participants exhibited a mean o f 81 dpm (range 23-134). On the 16 in (40.64 cm) Bike B, three participants exhibited a mean of76 dpm (range 41-100). On the 20 in (50.8 cm) Bike B, seven participants exhibited a mean of 92 dpm (range 42-141). On the 16 in (40.64 cm) Bike C, three participants exhibited a mean of 115 dpm (range 62-92). On the 20 in (50.8 cm) Bike C, seven participants exhibited a mean o f 76 dpm (37-120). On the 16 in (40.64 cm) Bike O, three participants exhibited a mean o f 71 dpm (range 44-103). On the 20 in (50.8 cm) Bike D, seven participants exhibited a mean of 54 dpm (range 40-73). On the 16 in (40.64 cm) Bike E, three participants exhibited a mean of 82 dpm (range 58-109). On the 20 in (50.8 136 j Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. cm) Bike E, seven participants exhibited a mean of 58 dpm (43-71). Due to the difference in tire circumference between the 16 in and 2 0 in bicycle tires, the expectation would be for a slightly higher rate of dpm on the 16 m bicycle. This was true for all bicycles in the series with the exception of Bike B. A reasonable explanation for this would be the extreme dpm scores for participant # 1. The ideal dpm fora 16 in and 20 in conventional bicycles respectively was 82 and 58. This estimation is based on the average dpm across all ten participants during maintenance sessions. However, the environmental constraints o f the gymnasium should be taken into consideration. In an outdoor setting or on an uneven surface, the dpm data might be different Consideration should be given to the amount o f force applied to the pedal for participants pedaling in an aggressive/passive manner or on a surface with an incline/decline. In addition, in a more natural setting, there would likely be more space to travel longer distances such as on a bike path or large parking lo t All of the trials in the gymnasium were limited to a distance of 12 m. In addition, due to the fact that participants were in the early stages of learning a new skill, many o f the trials were very short in length, perhaps only one or two meters per trial. The combination o f these circumstances (constraints) made it impractical for participants to settle into a comfortable cadence over an extended period o f time. From a theoretical standpoint, the environmental constraints o f an indoor setting could have an effect of the pedal rate. As Newell (1984) suggests, all elements of the environment, the task, and the individual must be taken into consideration when interpreting these data. From a dynamic systems perspective, systems undergoing change are characterized as being complex, coordinated and somewhat self-organizing (Clark & Whitall, 1989). Through this process order emerges through the interaction o f the many 137 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. components that make op such a complex system. In a dynamic systems analysis, it is important to identify variables that represent the essence of a particular behavior pattern. Kelso and Schoner (1988) refer to these as collective variables. The collective bicycle tiding variables that were examined in this study were head position and dOwnstrokes per minute. These are just two examples of the many potential variables that could be considered in the developmental landscape of bicycle tiding. Over time and horn bike to bike the percentage of upright head position increased from 35-49%. Perhaps the reason that participants did not demonstrate a significant increase in uhp could be that they were attending to other variables, such as steering participation or pedal cadence. Another explanation might involve eye position. It is possible that the head could have be down while the eyes were looking forward These reasons are in alignment with (Jobling, 1999: Sugden & Keogh, 1990) who suggest that children with MR have enduring problems with postural control and balance. Difficulties with postural control can have direct relevance to head position. Overall, there was evidence of extreme variability, particularly on Bikes A, B and C. However, the percentage of upright head position had a tendency to increase as participaiits reached criterion levels on Bikes D and E. In terms o f cadence, as measured by downstrokes per minute, participants had a tendency to increase the number o f downstrokes per minute, bike by bike, and then level out to a sufficient rate to maintain balance o f the bicycle. These findings are supported by Thelen (1994) in her study involving interlimb coordination of infants. When participants are presented with a novel task, intrinsic dynamics can be modified The preferred mode 13S I Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. of coordination at the start o fthe teaming process for cycling acquisition was a tendency to lo o k down and to pedal slowly. As the intrinsic dynamics began to change, participants becam e m ore proficient w ith cycling skills- Research Question 5: What is the social value o f learning to ride a conventional bicycle through the use o f adapted bicycles? The results obtained from the social validity questionnaire support the notion that a gradual introduction to bicycle-riding is less threatening than the traditional approach of trial and error (100%). Furthermore, parents indicated that children looked forward to attending cycling sessions for this study (100%). Results illustrate that the use of adapted bicycles made it possible for each child to ride a conventional bicycie( 100% agreement). Overall, results support the notion that children will ride bicycles with friends and/or family once they learn to ride. However, one parent disagreed and another parent strongly disagreed that their children would ride with others. The parent who strongly disagreed, explained that although her son teamed how to ride a conventional bicycle in an indoor setting, he refused to ride his bike in an outdoor setting near his home. This highlights the importance of skill generalization. Porretta (1988) explains that the lack of skill generalization may be the most pervasive and difficult educational problem for individuals with MR. Teaching skills in the environment where the skills will ultimately be used is preferable to artificial environments (Krebs, 2000). The negative response by the other parent may be due to the foct that the participant has only one 4 year old sibling. Other possible explanations would be that the participant does not have many neighborhood friends and/or his parents do not ride bicycles themselves. Social value 139 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. results support the idea that the ability to ride a conventional bicycle would increase the child’s physical activity level (9 out of 10). One parent disagreed with this statement. This was the same parent, whose child refused to tide his bicycle outside. Furthermore, there is strong support relative to parental perceptions for the notion that learning to ride a bicycle increases self-esteem and a feeling o f independence (100%). Studies involving psychosocial outcomes of Special Olympic athletes report increased self-concept (Wright & Cowden, 1986) and increased levels of perceived competence and perceived social acceptance (Gibbons & Busbakra, 1989). Results also illustrate that bicycling is a popular activity inm ost neighborhoods (9 out of 10). Finally, all respondents ( 10) agreed that bicycle tid in g is a lifelong sport/leisure a c tiv ity .Krebs (2000) concurs, stating that cycling is a useful skill and can be considered as a lifelong leisure pursuit Limitations 1. This research study was limited to two female and eight male participants (7-11 years of age) with mild MR. 2. The setting for this study was inside a gymnasium on the campus o f a large mid-west university. The gym was small (18.7 m by 11.2 m). Only 5.2 meters o f free space was available past the finish line. It is possible that the outcomes might have differed if the study took place in a larger gymnasium, or an outdoor setting. In addition, the gym had a tendency to be warm. As a result, room temperature may have affected the performance of participants. 3. Sessions for this study were conducted in the late afternoon and evening, (4-8 pm). Some participants came to the study directly from school and prior to eating dinner. Other participants came following mealtime. As a result, the time o f day may have 140 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. affected performance. In addition, the study took place in the winter months between November and January. As a result, the cold outdoor temperatures may have affected motivation, due to the fact that this newly acquired skill could not be implemented in a natural setting. 4. Exposure to training wheels or negative experiences on bicycles without training wheels could have possibly impacted participants’ performance. Children who were accustomed to riding with training wheels may have developed a tendency towards increased upper-body articulation. This can be described as leaning the upper torso to the right or left, in an attempt to balance the bicycle. This habit is contraindicatory to conventional bicycle riding. Those who have experienced falling while attempting to ride a conventional bicycle may have been fearful. In other instances, participants who experienced repeated failure, may have had low expectations. 5. Distance traveled, head position, and downstrokes per minute were the dependent variables for this study. Fear of contacting the wail may have prevented some participants from crossing the 12 m line. The same may be true for downstrokes per minute, in that the pedal rate may have been altered due to the proximity of the wall at the end of the gymnasium. Head position may have been affected due to various distractions in the environment Although participants were encourage to look at the Curious George banner at the end of the gym, many participants were visually attracted to the meter markers placed along the sidelines. Several participants counted the markers as they rode the bikes. Likewise, the rolling video-camera along the opposite sideline was a focal point for certain individuals. Although family members were not permitted inside the gymnasium, they were often just outside the doorway. At times, this caused participants 141 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. to look backward as they were riding the bicycle: Perhaps more stringent guidelines for individuals accompanying participants would have affected performance. 6. Braking and independently starting are skills that were outside the scope o f this study. However, once each child completed the study, the investigator spent 10-15 minutes working with the child on braking and independent starts. The parent was asked to come into the gym at this time, in order to receive instructions relative to practicing braking and independent starts with the child 7. The data collected relative to upright head position was based only on the position of the head Consideration was not given to eye position. In many instances, the head could have been down, when the eyes were looking forward or vice-versa. 8. Due to the multiple probe design, there may have been a practice effect for participants who received multiple probes on the conventional bike (Bike E). Implications for Practice This study shows, that children with mild MR can benefit from an adapted bicycle intervention. Ail 10 participants acquired the skill of riding a conventional bicycle. In terms of skill maintenance, 6 o u t o f 10 participants were able to maintain this level of performance. Four of the 10 participants revealed a slight decrease in performance during the maintenance session following acquisition. Three out o f 10 participants were able generalize the skill o f conventional bicycle riding at criterion levels ( 12 m , 3 out o f 5 trials). Furthermore, two participants were able to generalize this skill up to 8 m in distance T he fiv eremaining participants had limited success w ith response generalization, in that they were only able to generalize this skill up to 4 m. Based on these findings, it is important for teachers and coaches to provide ample practice time and 142 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. to emphasize maintenance and generalization of cycling skills in teaching children with mild MR. With regard to generalization, it is recommended that natural environments be utilized. Although the adapted bicycles axe designed for indoor use, after a child has progressed to riding a conventional bicycle, it is important to provide opportunities to practice in an outdoor environment Initially, it is recommended that children practice in an outdoor setting such as a parking lot, with free space and limited obstacles. Following this, learners can advance to bicycle trails and other venues that require more refined movements and reactions. It has been demonstrated that it is practical for physical educators and coaches to utilize adapted bicycles in their respective cycling programs. From a dynamic systems perspective, the use of a series of adapted bicycles represents a progressive task change. The presentation of a gradual continuum of more challenging bikes encouraged a shift by participants to more advanced modes o f functioning. Moreover, by initially providing the participants an appropriate task, participants were provided with successful experiences from the start In addition to increasing movement competence, participants were motivated to continue participation and meet new challenges as they progressed from bike to bike. From a practical standpoint, although the adapted bicycles are not currently available to the general public, it may be possible to obtain them in the foreseeable future. This purchase would be for adapted physical education teachers and therapeutic recreation specialists who teach a large number o f children. In this way, hundreds and thousands of children could learn to ride conventional bicycles and the cost for parents would be mhrimal. 143 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Relative to bicycle design, it is important to have access to various roller contours. Each child is different and the task must be adapted to fit the needs o feach individual. For the participants in this study, the #5 and #7 rollers were sufficient for adapting the task to individual needs. In addition, as the design becomes more streamlined in terms o f roller exchange, it would be less labor intensive if a quick release design were implemented as opposed to the current method of roller exchange. This would also decrease the amount of time that children would have to wait while transitioning between bicycles and/or rollers. The addition o f Bike C to the series was essential in bridging the gap between Bikes B and D. The increased forward motion of Bike C provided an invaluable experience prior to transitioning onto Bike D. However, the majority of trials and time continued to be concentrated on Bike D, the final bicycle in the adapted series. Perhaps a variation o f Bike D could be effectively utilized to make the transition even smoother. In terms o f bike size, both the 16 in (40.64 cm) and 20 in (50.8 cm) series were used in this study. Participants who were 49 in (124.46 cm) tall or less benefited from the use of the 16 in (40.64 cm) series, while participants 52 in (132.08 cm) and taller benefited from the use o f the 20 in (50.8 cm) series. There was one exception. Participant # 8 (height 48 in/121.92 cm) had more success on the 2 0 in (50.8 cm) bicycles. He was heavier and exhibited spasticity in his legs. The majority (7 out of 10) of children learned on the 20 in (50.8 cm) bicycle series. Therefore it is recommended that both sizes are made available for optimum use and success 144 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Future Research L Replicate the study with an additional number o f participants o f other ages and disabilities. 2 . Compare the use of the adapted bicycle series with other methods such as with existing patented devices/methods, or more traditional methods o f trial and error. 3. Increase the number o f trials to criterion on the conventional bicycle, in order for participants to more fully acquire the skill o f bicycle riding. 4. Utilize markers and biomechanical software to obtain precise data in re^rd to upper- body articulation and steering participation, head position and cadence. 3. Examine the effects of an adapted bicycle intervention on generalization to an outdoor setting. 6. Conduct studies examining variations of conventional bicycling skills such as the use o f geared bikes, riding with one hand, retrieving a water bottle, etc. Summary The purpose of this study was to investigate the effect of using a series o f adapted bicycles and feedback on the acquisition, maintenance^ and generalization of conventional cycling skiUs by children with mild MR. An applied behavioral analysis multiple probe design was utilized The adapted bicycle series consisted of four bikes; Bike A, Bike B, Bike C, and Bike D. The goal was to gradually progress to riding Bike E (conventional bike). 145 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. In the first session, a probe was taken with each bike to determine each participant's current a b ility level. Prior to each probe, the instructor to ld the participant to ride the bicycle as far as possible to the end o fthe gym. Next was the acquisition phase which included feedback. Feedback was in the form o f positive, positive/corrective or positive/specific feedback, relative to bead position, pedal rate and steering participation. Criterion for each bicycle was set at 3 out of 5 consecutive trials at a distance of 12 m. Once criterion was met on a particular bike, a generalization probe was administered. Upon advancement, another probe was taken on each bicycle in the series. Generalization was tested in the form of response generalization. Cones were placed by pairs in a zig-zag pattern across the gymnasium The participant was instructed to ride the bicycle through the cones to the end of the gym. The instructor provided a demonstration of the correct pathway. No feedback was given during generalization trials. Following acquisition of cycling skills on Bike E (conventional bicycle) the session ended. Maintenance and generalization phases were then initiated respectively. During the maintenance phase, the participant was instructed to ride the bike as far as possible. Each participant received a maximum of 15 maintenance trials. During the generalization phase, the cones were set up and the participant was instructed to ride through the cones in a weaving pattern as far as possible. Each participant received a maximum of 15 trials. Acquisition results indicate that all ten participants acquired the skin of riding a conventional bicycle at criterion level (3 out of 5 consecutive trials at 12 m). These results represent a 100% success rate in terms o f acquisition of conventional cycling 146 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. skills. The majority of participants ( 6 oat o f 10) demonstrated maintenance of conventional cycling skills at criterion levels. Across ail ten participants, maintenance was evident an average o f47% o f the time. Three often participants were able to generalize this skill at criterion levels. The remaining participants demonstrated lower levels of generalization. Visual examination ofthe graphic display of data supports the notion o f dynamic systems, that unstable patterns are predictors o f change (Kelso et aL, 1993). Extreme variability in the data paths was followed by an increase in performance. The shift from bike to bike represented a change in the task that consequently perturbed the movement system towards instability. Additionally, the data collected relative to head position and pedal rate revealed that the preferred mode of cycling at the beginning of the learning process was capable of being altered. Initially, upright head position was extremely variable. As upright head position became more consistent, cycling proficiency increased. As upright head position became more consistent, cycling proficiency increased. Likewise, participants initially proceeded with caution in terms of pedal rate. As the number o f downstrokes per minute increased and stabilized, cycling proficiency increased. This demonstrates that as instrumental variables fall into place across the developmental landscape, performance is affected in a positive manner. 147 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UST OF REFERENCES Adams, J. A. (1971). A closed-loop theory o f motor learning Journal o f Motor B eh a vio r, J, 111-150. American Association on Mental Retardation. (1992). M ental retardation: Definition, classification, and systems ofsupports (9th ed.). Washington DC: A uthor. AnsheL, M. H. & Singer, R. N. (1980). Effect o f learner strategies with modular versus traditional instruction on motor skill learning and retention. Research Quarterly For Exercise and Sport, 51, 451-462. Baddeley, A. D. & Longman, D. J. A. (1978). 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J. & Porretta, D. L. (1999). Sport/leisure skill learning by adolescents with mild mental retardation: A four-step strategy. Adapted Physcial Activity Quarterly, 16, 300-515. Zanzone, P. G. & Kelso, J. A. S. (1991). Experimental studies of behavioral attractors and their evolution with learning. In J. Requm& G. E. Stelmach (Eds.), T u to ria ls in motor neuroscience (pp. L21-133X Dordrecht, The Netherlands: Kluwer Academic Publishers. Zigler, E. & Hodapp, R. M (1986). Understanding mental retardation. New York: Cambridge University Press. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX A BICYCLE PHOTOGRAPHS i 160 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. B ikeB j 161 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. BikeC BikeD 162 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. B i k e E Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX B ADAPTED BICYCLE DESCRIPTION The independent variable for this study is the use o f a series of four adapted bicycles (see Appendix A) created by Dr. Richard Klein, professor emeritus of mechanical engineering from the University of Illinois. Dr. Klein provided the following description of the adapted bicycles. Three of the four adapted bicycles feature 12 inch long by 3.25 inch (mid-point) diameter rollers in lieu of conventional pneumatic tires. The rollers are made of solid polyurethane rubber molded onto a two inch OJD. (outside diameter) steel tubular core. The thickness of the molded polyurethane covering material is 518 inch, and thus the rollers start out as cylindrical at 3.25 inches in diameter (2" +- 5/8" + 5/8") prior to being crowned by machining on a modem lathe. The inner steel cores (for each of the respective rollers) are hollow, with a 1.25-inch internal diameter. The rollers are first internally bored on each end to accept a 1 3/8-inch x l/2-inch standard flange bearing Then, using the internal bearing bores as centering mounts, the outer polyurethane rollers are turned on a numerically controlled (NC) lathe to exacting proportions. In short, each roller is machined to have a precisely controlled crown, where the description of the respective crowns are termed in "arc-inches" using tire industry terminology. Thus, each roller has a crown in its respective center, which gradually tapers down to the ends. Moreover, the crown can be varied (in the NC lathe operation) to give the respective rollers differing arc-inch crowns. The rollers to be used in this study have crowns ranging 164 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. from 60.15 to 180.05 arc-inches. The rollers have been mounted onto a 16 inch (the diameter), single-speed bicycle frame. The frame o f the bicycle is adapted in its structure (by frame modification) to preserve the original ground points of contact Hence, the frame accommodates the rollers by extending downward as the rollers have a significantly smaller diameter as compared to the original 16-inch bicycle tire configuration. Moreover, to provide a means of propulsion, a drive train system exists using a standard bicycle chain and rear sprocket, which in turn drives a standard 5/16- inch automotive style V-belt that in turn drives the rear roller. The rollers are designed such that all rear rollers have been machined at the respective centers) to have an accommodating V-groove to accept the drive V-belt The gearing is altered sufficiently to slow the training bicycle's forward speed down relative to pedaling cadence. The bicycle's gearing is about one-third that of a conventional similarly sized bicycle. The first two bicycles in the series have modified drive trains. This adjustment converts the design to that of a fixed gear as opposed to a free wheel or "coaster brake" system." The fourth adapted bicycle in the series features a wide, 16x8x5 inch inflatable garden tractor style tire as opposed to rollers. To summarize, there are four adapted bicycles in this series featuring a combination of rollers, wide tires, lower gearing ratios, and modified drive trains, designed to accommodate the needs of children in the acquisition of conventional cycling skills. 165 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX C ILLUSTRATED PATENTS Note; The numbers associated with the following illustrations refer to specific parts of the patented equipmenL Refer to the list of references for information on patents. 166 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 3 0 1 4 ^ / 4 4 4 0 Egley, 1994 Cudmore,l972 167 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. GeLIer, 1991 Harrison, 1995 168 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Henrichs, 1996 169 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. BCiauss, 1993 Nanassi, 1995 170 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. t) Pearson, 1993 171 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Saunders, 1989 172 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX D PILOT DATA 173 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Acquisitions • Maintenance^ A Generalizations O Probes & A I * • « €—», L-, E T C«I E R /V S D“ TRIALS Participant #t-P 174 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Acquisitions • Maintenance^ A Generalizations O Probes© D A 1 I I S T A’ 2 A N C E 8“' a a a—« I / M B»f| ® * ° I E T " 1 E i f ] i R S * ■ 9 O i n „ 9 n & i TRIALS Participant #2-P 175 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. i 1-2 § 1 3 0 3 c ■ -2 2 3 B « S l s i • I tn_4 < t-* Participant #3'PParticipant I v T i. » r - -X. Q_e«t- 176 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. cI » i> .2 s H i * f l s l Participant #4*P Participant 177 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. o . < I •I It o <= o S s II J® to o « I itt« s |o 5 s Q_tot- I7S Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX E BEHAVIORAL AND SOCIAL SCIENCES HUMAN SUBJECTS INSTITUTIONAL REVIEW BOARD (IRB) j 179 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. BEHAVIORAL. AND SOCIAL SCIENCES HUMAN SUBJECTS INSTITUTIONAL REVIEW BOARD (IRB) The Ohio State University. Columbus. OH 43210 Research Involving Human Subjects ACTION OF THE INSTITUTIONAL REVIEW BOARD FtiU Committee Review X Original Review x Expedited Review Continuing Review Amendment With regard to the employment o! human subjects in the proposed research protocol: 01 BOW THE USE OF ADAPTED BICYCLES IN THE ACQUISITION. MAINTENANCE AND GENERALIZATION OF CONVENTIONAL CYCLING SKILLS BY CHILDREN WITH MILD MENTAL RETARDATION, David L. Porretta. Tammy L. Burt; Physical Activity & E d u catio n al S e rv ic e s THE BEHAVIORAL AND SOCIAL SCIENCES HUMAN SUBJECTS IRB HAS TAKEN THE FOLLOWING ACTION: APPROVED DISAPPROVED X APPROVED WfTH CONDITIONS WAIVER OF WRITTEN CONSENT GRANTED ' Conditions stated by the IRB have been met by the Investigator and; therefore, the protocol is APPROVED. • It is the responsibility of the principal investigator to retain a copy of each signed consent form for at least three (3) years beyond the termination of the subject's participation in the proposed activity. Should the principal investigator leave the University, signed consent forms are to be transferred to the Human Subjects IRB for the required retention period. • This application has been approved for the period of one year. • You are reminded that you m ust promptly report any problems to the IRB and that no procedural changes may be made without prior review and approval. • You are also reminded that the identity of the research participants must be kept j confidentiaL Date: August 24.2001 Signed: HS-Q25B (Rev. 2/94) 180 with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX F INFORMED CONSENT / 181 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. T * K - E School of Physical Activity Phone 614-Z9Z-5679 OHIO and Educational Services FAX 614-292-7229 SPOE UNIVERSITY CONSENT FOR PARTICIPATION IN SOCIAL AND BEHAVIORAL RESEARCH Protocol title: The me Of adapn-d hif-m-ly* ; t» -x-qmaition- nafmrnmrtt^tirf^nm lrntinniif’ennmtrinnal cycling stalls hv r-hitrfreg with m 'M i w m l retardation Protocol number 01B0147 Principal Investigator Dr. David Porrata I consent to my participation in (arm y child's participation in) research being conducted by Tammy Burt of The Ohio State University and his/her assistants and associates. The investigators) has explained the purpose of the study, the procedures that will be followed, and the amount of time it will take. I understand the possible benefits, if any. of my participation (and/or my child's participation). I know that I can (and/or my child can) choose not to participate without penalty to m e (and/or my child). If I agree to participate. I can (and/or my chftd can) withdraw from the study at any time, and there will be no penalty. • I consent to the use of audiotapes and/or videotapes, t understand how the tapes wilt be used for this study. • t consent to the use of photographs. I understand how the photographs win be used for this study. I have had a chance to ask questions and to obtain answers to my questions. I can contact the investigators at (614)292-0849 or (6141830-0659. If I have questions about my rights as a research participant. I can call the Office of Research Risks Protection at (614) 686-4792. I have read this form or I have had it read to me. I sign it freely and voluntarily. A copy has been given to m e. Print the name of the participant; D ate;______Signed: /PWflcfMnO S ig n e d : ______S igned: I (Panop«ttocadg^nr ar tieamr tum aumi npnsantaOn) (Fnoon auftariatf toeonswir ArpvttapwiC t n q u n d ) W itness: |W fw > n q u n 4 HS4BT(Rmr. 05iav IS 2 with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX G FLOOR DIAGRAM i 183 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Cone placements « Gymnasium dimensions 18.7 m x t L2 m Generalization only Video-camecL 9 m. r A 12 m < V S o n line t_5 m Ready Line investigator 184 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX H DATA COLLECTION SHEETS 185 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Coding Sheet A Phase ______Session ______Date______Participant Total # of Trials Trial I Trial 11 Trial 21 T rial3 l Distance; Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 2 Trial 12 Trial 22 Trial 32 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 3 Trial 13 Trial 23 Trial 33 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 4 Trial 14 Trial 24 Trial 34 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trials Trial 15 Trial 25 Trial 35 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 6 Trial 16 Trial 26 Trial 36 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 7 Trial 17 Trial 27 Trial 37 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: TrialS Trial 18 Trial 28 Trial 38 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 9 Trial 19 Trial 29 Trial 39 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: Trial 10 Trial 20 Trial 30 Trial 40 Distance: Distance: Distance: Distance: Bike: Bike: Bike: Bike: indicate bike as A. B. C D or E Bicycle Probe=BP Generalization Probe=GP 186 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Coding Sheet 3 Participant's Name. ______D ate______Phase. T rial 1 eDownsroket 3 sec/m w Trial U *Do'»«tstrokes B ike_____ Elapsed Time B ik e____ „ Elapsed Tune sec T ria l! 3 Trial IZ *Downstrokes 3 see/mm B ite _____ Elapsed Time ____ B ike_____ BaoacdTtine T hat I 3 sec/m ut T nai 13 « Howtwrm Ir« fpr/im n B ik e_____ Elapsed Time Bike _ ESaosedTune _ J « c . T h a i* * Downstrokes 3 sec/rnta T nai U * Dowmtrokes 3 sec/m in Bike Elapsed Time sec. B ik e____ Q am ert Ttm e fme* T h alS 9 sec/m ui T nai 15 * O o w m trete 3 sec/m ut B ik e_____ Elapsed Time Sec. Bike Elapsed Tune sec. T hai 6 eDownstroke* 3 w t/m in Trial 16 • Dowftftmkei sec/nuik B ite FlanSfdTime sec Bike ElansedTIme sec. T eal 7 • Downstrekes 3 sec/nuik T nai 17 *DnwiH(rekn 3 sec/mm Phptnrt Tine see. Bike Elapsed Tim e sec. T h alS *Dov«ntrakes 3 sec/mu* T nai IS * Dowftstmfces B ite ______s c c . Bike Elapsed T iinc _ sec. Trial 9 * Dowmtrokes 9 teC/reua T nai 19 * Oowasirotces 3 sec/m ia B ite _____ sec. B ik e_____ B am ed Tim e sec. T nai (0 * OnwmcrokM 9 sec/m ut T nai 20 * Oowftsmxte* Bike Elapsed Time ______see B ik e____ Elapsed T une sec. 187 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. C oding S heet C Participant's Name. S ession ______D ate_ . P hase. Trial_ B ite . Partial Interval Recording: 2 second intervals » Intervals w f HP up je 100 = Head Position Up= (>■) Head Position Down= (-) Total Intervals ___ I X X ZE 1 ------1 10 12 14 16 IS Trial Bike Partial Interval Recording: 2 second intervals » Interval? wf HP,ug, I 100 = Head Position lTc*=x f+) Head Position Down= (-) Total Intervals I I V I T X X X s 10 12 1 4 16 IS Trial______B ite______Partial Interval Recording: 2 second intervals » Intervals w f HP up j t 100 = _ Head Position Up= f+) Head Position Down= (-) Total Intervals l \ V > t x r~—i s 10 12 1 4 16 IS T rial. B ite . Partial Interval Recording: 2 second intervals * Intervals w f HP u p jc 100=_ Head Position Up= (+) Head Position Down= (-) Total Intervals X X to 12 14 16 18 T rial. .B ite . Partial Interval Recottfing: 2 second intervals » Intervals w f HP un jt 100 =. Head Position Uq =(-i-> Head Position Dowa= (-) Total Intervals X X T: ----- I 0 2 4 S 10 12 1 4 16 13 Trial______B ite Partial Interval Recording: 2 second intervals 0 Intervals w f HP tro j t 100 = Head Pttsitioa Ups (+) Head Position Down= (-) Total Intervals r I X 10 12 1 4 16 13 Trial B ite ______Partial Interval Recording: 2 second intervals * Intervals wf HP up J t ioo = _ Head Position Ut*= M Head Position Down= f-) Total Intervals ~ '" i > i ~t t r~ I 0 2 4 3 10 12 1 4 1 6 18 Trial______B ite Partial Interval Recording: 2 second intervals § Intcrrab HP up. j t 100 = Head Position Up=(-v) Head Position Down= (-) T otal Intervals LZ X a s IQ 12 1 4 16 18 188 with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX I Procedural Reliability Checklist Yes No L Did the participant wear a helmet while riding the b i c y c le ? ______ 2. Did the investigator say "Ready? Here we go!" at the start o f each trial? ______ 3. Did the investigator release the bicycle at the start of each tnai? ______ Did the investigator provide positive feedback following baseline and probe conditions? ______ Did the investigator provide positive/corrective or positive/specific feedback at the completion o f each tnai during intervention? ______ 6 . Did the participant dismount the bicycle and walk back to the starting line at the completion of each trial? ______ 7. Did the investigator announce "stop” at the completion of each trial? 189 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX J Social Validity Questionnaire Circle the number that best corresponds to the following statements. l=Strongly Agree 2=Agree 3=Disagree 4=Strongly Disagree SA A D SD 1. A gradual introduction to bicycle-riding is less threatening than the traditional approach o f trial and e rro r. 2 4 2 . My child looked forward to attending cycling sessions. ? 4 3. The use of adapted bicycles made it possible for my child to ride a conventional bicycle. 4. My child will ride his/her bicycle with friends and/or family. 5. The ability to ride a conventional bicycle will increase my child’s level of physical activity. 6. The ability to ride a conventional bicycle will increase my child’s feeling of independence. 4 Learning to ride a conventional bicycle has boosted my child’s selfesteem . Bicycle riding is a popular recreational activity in my neighborhood. 4 9. Bicycle riding is a lifelong sport/leisure activity. 4 [90 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPENDIX K Interobserver Agreement Observation Schedule Participant 1 Session I Participant 2 Session 2 Participants Sessions Participant 4 Session 4 Participants Sessions Participant 6 Session 6 Participant? Session 7 Participant 8 Session 8 Participant 9 Session I Participant 10 Session 2 / I9t Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.