HIP FUNCTION AND RUNNING MECHANICS IN YOUTH ATHLETES Kelly Roy Sheerin PGDip (Musculoskeletal Physiotherapy), BHSc (Physiotherapy), BSc. A thesis submitted to the AuCkland University of Technology in fulfilment of the degree of Master of Health SCienCe June 2011 TABLE OF CONTENTS List of Figures ........................................................................................................................... 2 List of Tables ............................................................................................................................. 2 Attestation of authorship ......................................................................................................... 4 Candidate Contributions to Co-authored papers.................................................................... 5 Acknowledgements .................................................................................................................. 6 EthiCal approval ........................................................................................................................ 7 AbstraCt ...................................................................................................................................... 8 Chapter 1 .................................................................................................................................... 9 Introduction and rationale (Preface) .................................................................................... 9 Background ......................................................................................................................... 9 Structure of the thesis ....................................................................................................... 11 Chapter 2 .................................................................................................................................. 13 Hip strength and lower limb alignment as risk factors and intervention strategies for running related lower limb injuries in young athletes. .................................................................... 13 Overview ............................................................................................................................ 13 Methods ............................................................................................................................. 16 Findings ............................................................................................................................. 18 Conclusion ......................................................................................................................... 44 Chapter 3 .................................................................................................................................. 45 Reliability of strength measures in young athletes. .................................................. ......... 45 Overview ............................................................................................................................ 45 Introduction ........................................................................................................................ 45 Methods ............................................................................................................................. 46 Results ............................................................................................................................... 48 Discussion ......................................................................................................................... 51 Recommendations for future research .............................................................................. 52 Conclusion ......................................................................................................................... 52 Practical implications ......................................................................................................... 52 Chapter 4 .................................................................................................................................. 53 Reliability of 3D frontal plane hip and knee range of motion during running in young athletes. ............................................................................................................................. 53 Overview ............................................................................................................................ 53 Introduction ........................................................................................................................ 53 Methods ............................................................................................................................. 54 Results and discussion ...................................................................................................... 55 Conclusion ......................................................................................................................... 57 Chapter 5 .................................................................................................................................. 58 Effects of a lower limb functional exercise programme aimed at minimising knee valgus angle on running kinematics in youth athletes .................................................................. 58 Overview ............................................................................................................................ 58 Introduction ........................................................................................................................ 58 Methods ............................................................................................................................. 60 Results ............................................................................................................................... 64 Discussion ......................................................................................................................... 66 Conclusion ......................................................................................................................... 67 Practical implications ......................................................................................................... 68 Chapter 6 .................................................................................................................................. 69 1 Discussion and conclusions .............................................................................................. 69 Thesis limitations and delimitations ................................................................................... 71 Future directions ................................................................................................................ 72 Conclusion ......................................................................................................................... 73 ReferenCes ............................................................................................................................... 74 Appendix 1 ............................................................................................................................... 82 AUT ethics approval .......................................................................................................... 82 AUTEC approval memorandum ............................................................................................. 88 Appendix 2 ............................................................................................................................... 89 Additional data: Reliability of 3D frontal plane Hip ab/adduction range of motion during running in young athletes. ................................................................................................. 89 Appendix 3 ............................................................................................................................... 91 Conference abstract: Reliability of lower limb strength, flexibility and 3D gait measures during running in young athletes ....................................................................................... 91 Appendix 4 ............................................................................................................................... 93 Conference abstract: The reliability of lower limb isometric strength and hip flexibility measures for young athletes ............................................................................................. 93 LIST OF FIGURES Figure 1: Overview of masters thesis chapter flow. ............................................................ 11 Figure 2: Marker placements for running lower limb kinematic analysis. ........................... 62 Figure 3: Conceptual model for the development of lower limb overuse injuries. .............. 70 LIST OF TABLES Table 1. Studies evaluating the relationship between hip muscle strength and lower limb overuse injuries. ................................................................................................... 21 Table 1 cont. Studies evaluating the relationship between hip muscle strength and lower limb overuse injuries. ................................................................................................... 22 Table 2. Studies evaluating the relationship between lower limb alignment and overuse injuries. ................................................................................................................