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Cordingleyz2020m.Pdf (1.899Mb) Lakehead University Knowledge Commons,http://knowledgecommons.lakeheadu.ca Electronic Theses and Dissertations Electronic Theses and Dissertations from 2009 2020 The immediate effects of Tai Chi on the postural stability, muscle activity and measures of inferred ankle proprioception of healthy young adults Cordingley, Zachary http://knowledgecommons.lakeheadu.ca/handle/2453/4683 Downloaded from Lakehead University, KnowledgeCommons Running head: EFFECTS OF TAI CHI ON POSTURAL STABILITY AND ANKLE PROPRIOCEPTION The Immediate Effects of Tai Chi on the Postural Stability, Muscle Activity and Measures of Inferred Ankle Proprioception of Healthy Young Adults Zachary Cordingley Supervisor: Dr. Paolo Sanzo Committee: Dr. Carlos Zerpa and Dr. Kathryn Sinden Lakehead University EFFECTS OF TAI CHI ON POSTURAL STABILITY AND ANKLE 2 PROPRIOCEPTION Table of Contents Table of Contents ...................................................................................................................... 2 List of Figures ........................................................................................................................... 6 List of Tables .......................................................................................................................... 10 List of Abbreviations .............................................................................................................. 11 Abstract ................................................................................................................................... 13 Chapter I: Literature Review .................................................................................................. 14 What is Tai Chi? .................................................................................................................. 14 Fundamentals of Balance .................................................................................................... 16 Fundamentals of Postural Stability ..................................................................................... 18 Mechanics of postural sway. ........................................................................................... 21 Function of sensory input. ............................................................................................... 22 i.) The visual system .................................................................................................... 22 ii.) The vestibular system ............................................................................................. 23 iii.) The somatosensory system ..................................................................................... 24 Integration of sensory input. ............................................................................................ 24 Challenging postural stability .......................................................................................... 25 Center of pressure based measures of postural stability .................................................. 25 The effects of Tai Chi on measures of postural stability. ................................................ 27 EFFECTS OF TAI CHI ON POSTURAL STABILITY AND ANKLE 3 PROPRIOCEPTION Gaps in Tai Chi research on postural stability. ................................................................ 29 An Introduction to Proprioception ...................................................................................... 33 Primary sources of proprioception .................................................................................. 35 Secondary sources of proprioception. ............................................................................. 37 Proprioceptive impairment. ............................................................................................. 37 Importance of ankle proprioception ................................................................................ 38 The effect of Tai Chi on proprioception. ......................................................................... 43 Inferring ankle proprioception: Electromyography. ........................................................ 49 Inferring ankle proprioception: Spectral analysis. ........................................................... 52 Research Problem ................................................................................................................ 55 Purpose ................................................................................................................................ 55 Hypotheses .......................................................................................................................... 55 Chapter II: Methods ................................................................................................................ 57 Participants .......................................................................................................................... 57 Recruitment. .................................................................................................................... 57 Inclusion/exclusion criteria. ............................................................................................. 57 Procedure ............................................................................................................................. 58 Instrumentation ................................................................................................................ 58 Set-up. .............................................................................................................................. 59 Warm-up. ......................................................................................................................... 61 EFFECTS OF TAI CHI ON POSTURAL STABILITY AND ANKLE 4 PROPRIOCEPTION Normalizing electromyography. ...................................................................................... 62 Data collection. ................................................................................................................ 62 Tai Chi intervention. ........................................................................................................ 63 Concluding the session. ................................................................................................... 64 Data processing................................................................................................................ 64 Statistical analysis............................................................................................................ 65 Chapter III: Results ................................................................................................................. 67 Demographics ...................................................................................................................... 67 Scalar Center of Pressure Based Measures ......................................................................... 67 Mean Sway Velocity. ...................................................................................................... 67 95% Elliptical Area. ........................................................................................................ 74 Electromyography Based Measures .................................................................................... 82 R-TA. ............................................................................................................................... 82 L-TA. ............................................................................................................................... 82 R-GM ............................................................................................................................... 82 L-GM ............................................................................................................................... 86 Spectral Analysis Based Measure ....................................................................................... 89 Relative Power ................................................................................................................. 89 Chapter IV: Discussion ........................................................................................................... 90 Scalar COP-Based Measures ............................................................................................... 90 EFFECTS OF TAI CHI ON POSTURAL STABILITY AND ANKLE 5 PROPRIOCEPTION Root Mean Square of the Electromyography Measures ...................................................... 93 Spectral Analysis of Center or Pressure Sway .................................................................... 97 Chapter VI: Limitations and Future Directions ...................................................................... 98 Limitations .......................................................................................................................... 98 Future Directions ................................................................................................................. 99 Chapter VII: Conclusion ....................................................................................................... 102 References ............................................................................................................................. 103 Appendix-A: Cover Letter .................................................................................................... 127 Appendix-B: Informed Consent ...........................................................................................
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