Influence of a Marching Snare Drum System on Joint Kinematics, Electromyography, and Contact Pressure by Andrea Michelle Sumner A dissertation submitted to the Graduate Faculty of Auburn University in partial fulfillment of the requirements for the Degree of Degree of Doctor of Philosophy Auburn, Alabama May 6, 2012 Keywords: load carriage, EMG, contact pressure, kinematics, kinetics Copyright 2012 by Andrea Michelle Sumner Approved by Wendi H. Weimar, Chair, Associate Professor of Kinesiology David D. Pascoe, Professor of Kinesiology Richard D. Good, Professor of Music Joellen M. Sefton, Assistant Professor of Kinesiology ABSTRACT Each year thousands of students participate in marching band. Many participate by carrying a flag, baton, woodwind or brass instrument, or drum. The drumline is of particular interest due to the unique and restricting nature of the instrument: a load carried anterior to the body with the only points of contact on the body at the shoulders and across the abdominal area. The influence of load carriage research on gait and joint mechanics, muscle activity, and contact pressure can be seen in the ever changing backpack designs and recommendations of load mass; however, there still remains a lack of research on marching band load carriage. The purposes of this investigation were: 1) to determine the influence of a standard marching snare drum system (SDS) and a modified marching snare drum system (MDS) on trunk and lower extremity kinematics while standing and marching; 2) to determine the muscular demand placed on the erector spinae, of individuals wearing a SDS and MDS while standing and marching; and 3) to determine the contact pressures at the shoulders and abdominal region of individuals wearing the SDS and MDS systems. The results showed that the SDS during stationary tasks decreased hip flexion, and increased trunk flexion, ankle plantarflexion, ES EMGAVG and EMGPEAK as a result of the changes in posture, and contact pressures at the shoulders. When the participants wore the SDS while marching, the results showed increased trunk flexion, and increased ES EMGAVG and EMGPEAK as a result of the changes in trunk angle. When implementing ii a lumbar belt there were similar significant findings at the joints and muscle activity level from the unloaded condition only, suggesting that the implementation of the lumbar belt did not alter the marching kinematics of the performer. The MDS condition however, did result in lower contact pressure values at the shoulders and higher pressures at the abdominal region, indicating a redistribution of pressure and load to the belt, hips, abdomen, and pelvic girdle and off of the shoulders. Therefore it can be concluded that implementing a lumbar belt to a SDS system ameliorates skin contact pressure and discomfort at the shoulders, potentially decreasing the occurrence of an injury, and anecdotally providing relief to the participants. iii ACKNOWLEDGMENTS The author would like to thank Dr. Wendi Weimar for not only introducing her to the field of Biomechanics, but for the dedication to her academic and professional development and maturity. Thanks to Dr. Weimar’s countless hours of guidance, wisdom, patience, and support, I was able to push myself academically to higher standards which allowed me to be the educator and researcher that I am today. The author would like to thank the members of her committee, Dr. David Pascoe, Dr. Richard Good, and Dr. JoEllen Sefton for their time, patience, and dedication to my development throughout this process and my academic career at Auburn University. The author would also like to thank Dr. David Shannon for his willingness to serve as the outside reader, and Dr. Sara Wolf for her assistance, advice, and support. The author would also like to thank the members of the Sport Biomechanics Laboratory: Jay Patel, Braden Romer, John Fox, and Jared Rehm for the tireless help, hard work, and support throughout the data collection process. To the members of the Auburn University Marching Band Drumline, the author is very thankful for their patience and willingness to participate. Most importantly, the author would like to thank her parents, Gordon and Vicki, for their unwavering support and encouragement throughout her entire educational career. Without their love, belief, and patience during the long journey, this would not have been possible. I love you both TMAM. iv Table of Contents Abstract ........................................................................................................................................ ii Acknowledgments ....................................................................................................................... iv List of Tables ............................................................................................................................. viii List of Figures ............................................................................................................................. ix List of Abbreviations ................................................................................................................. xii Chapter I: Introduction .................................................................................................................. 1 Purpose ............................................................................................................................ 15 Hypotheses ..................................................................................................................... 16 Limitations ..................................................................................................................... 17 Delimitations .................................................................................................................. 17 Definition of Terms......................................................................................................... 18 Chapter II: Review of Literature ................................................................................................ 20 Section 1: Biomechanical Effects of Posterior & Combined Anterior/Posterior Load Carriage................................................................................................. 21 Section 2: Biomechanical Effects of Anterior Load Carriage ....................................... 27 Section 3: Muscle Activity & Contact Pressure ............................................................. 32 Section 4: Lumbar Belt Implementation ........................................................................ 43 Section 5: Summary ........................................................................................................ 49 Chapter III: Methods .................................................................................................................. 53 v Participants ...................................................................................................................... 54 Setting ............................................................................................................................ 54 Materials ......................................................................................................................... 55 Instrumentation .............................................................................................................. 61 Design & Procedures ...................................................................................................... 69 Experimental Design & Data Analysis .......................................................................... 73 Chapter IV: Results .................................................................................................................... 75 Section 1: Participant Demographics ............................................................................ .76 Section 2: Joint Kinematics ............................................................................................ 76 Section 3: Erector Spinae Muscle Activity ..................................................................... 85 Section 4: Contact Pressure ............................................................................................ 90 Chapter V: Discussion ............................................................................................................. .93 Section 1: SDS & MDS Conditions on Joint Kinematics ............................................... 94 Section 2: SDS & MDS Conditions on ES Muscle Activity .......................................... 99 Section 3: SDS & MDS Conditions on Contact Pressure ............................................. 102 Section 4: Summary & Future Research ....................................................................... 105 References .............................................................................................................................. .109 Appendix A: Preliminary Medical Questionnaire (PMQ) ........................................................ 116 Appendix B: Informed Consent ................................................................................................ 117 Appendix C: ANOVA Table for the Effect of Load Carriage on Joint Kinematics ................. 120 Appendix D: ANOVA Table for the Effect of Load Carriage on Joint Kinematics ................. 121 Appendix E: ANOVA Table for the Effect of Load Carriage on ES sEMG ............................ 122 Appendix F: ANOVA Table for the Effect of Load Carriage on Peak Contact