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Effects of Workrate and Seat Position on Frontal Plane Knee Biomechanics in Recumbent Cycling

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Effects of Workrate and Seat Position on Frontal Plane Knee Biomechanics in Recumbent Cycling University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 8-2019 Effects of Workrate and Seat Position on Frontal Plane Knee Biomechanics in Recumbent Cycling Tianyi Lu University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Recommended Citation Lu, Tianyi, "Effects of Workrate and Seat Position on Frontal Plane Knee Biomechanics in Recumbent Cycling. " Master's Thesis, University of Tennessee, 2019. https://trace.tennessee.edu/utk_gradthes/5530 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Tianyi Lu entitled "Effects of Workrate and Seat Position on Frontal Plane Knee Biomechanics in Recumbent Cycling." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Kinesiology and Sport Studies. Songning Zhang, Major Professor We have read this thesis and recommend its acceptance: Jared Porter, Joshua Weinhandl Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Effects of Workrate and Seat Position on Frontal and Sagittal Plane Knee Biomechanics in Recumbent Cycling A Thesis Presented for the Master of Science Degree The University of Tennessee, Knoxville Tianyi Lu August 2019 Copyright © 2019 by Tianyi Lu All rights reserved. ii ACKNOWLEDGEMENT First and foremost, I would like to thank my parents Xiaoping Lu and Xiaorong Yan. Without their support, I would not be able to have the chance to start my program at the University of Tennessee, Knoxville. I would also like to thank my research advisor, Dr. Songning Zhang, for his endless academic guidance, patience and efforts throughout the process. He is one of the most knowledgeable people in the biomechanics field and his assist and encouragement has helped me improved a lot as a researcher. I could not ask for a better mentor. In addition, I would like to thank my committee members, Dr. Jared Porter and Dr. Joshua Weinhandl for their valuable advice on the thesis project. I would also like to thank my fellow colleague Tanner Thorsen, along with Erik Hummer and Daniel Sample for their help with data collection and processing. Last but not the least, I would like to thank Eddie “The Beast” Hall for being my biggest motivation. Eddie Hall, as the strongest human being of all time, has done the greatest feat of strength ever, the “Impossible 500kg Deadlift”. His determination, intensity and dedication to his goals have impacted and helped me overcome any obstacle I faced, not only throughout the thesis project, but my entire life. iii ABSTRACT In cycling study, there were limited research on recumbent bike kinetics, especially the frontal plane. Increased internal knee abduction moment (KAbM), on the frontal plane, has been shown to be an effective predictor of knee osteoarthritis. The purpose of this study was to examine the effects of different workrates and seat positions on knee biomechanics during stationary recumbent cycling. Fifteen participants cycled on a recumbent ergometer in 6 test conditions of pedaling in far, medium and close seat positions in each of two workrates of 60 and 100 W, at the cadence of 80 RPM. A three-D motion analysis system and a pair of custom-made instrumented pedals were used to collect kinematic and kinetic data. A 3 ´ 2 (seat position ´ workrate) repeated measures analysis of variance (ANOVA) was used to examine the effect of seat positions and workrates on selected variables of interest. Increased workrates significantly increased peak KAbM and knee extension moment. Different seat positions did not change either peak KAbM or knee extension moment. Due to the larger Q-factor for the recumbent bike used in the study, future study should examine the knee biomechanics with smaller Q-factors, as well as the lower limb muscle activities in recumbent cycling. iv TABLE OF CONTENTS CHAPTER I INTRODUCTION ................................................................................................. 1 Statement of Problem .............................................................................................................. 4 Significance ............................................................................................................................ 4 Hypothesis .............................................................................................................................. 5 Delimitations .......................................................................................................................... 5 Limitations .............................................................................................................................. 5 CHAPTER II LITERATURE REVIEW ...................................................................................... 6 Background of Cycling ........................................................................................................... 6 Benefits of Cycling ............................................................................................................. 6 Injury Risks of Cycling ....................................................................................................... 7 Upright Cycling Biomechanics................................................................................................ 7 Terminology ....................................................................................................................... 7 Kinematics .......................................................................................................................... 8 Kinetics ............................................................................................................................. 10 Recumbent Cycling Biomechanics ........................................................................................ 12 Advantages of Recumebnt Cycling .................................................................................... 13 Equipment & Body Positions of Recumbent Cycling......................................................... 14 Kinematics ........................................................................................................................ 15 Kinetics ............................................................................................................................. 19 CHAPTER III METHODS ....................................................................................................... 25 Participants ........................................................................................................................... 25 Instrumentation ..................................................................................................................... 25 3D Motion Analysis System .............................................................................................. 25 Recumbent Ergometer ....................................................................................................... 26 Customized Pedals ............................................................................................................ 26 Procedures ............................................................................................................................ 27 Data and Statistical Analysis ................................................................................................. 28 CHAPTER IV EFFECTS OF WOEKRATE AND SEAT POSITION ON FRONTAL AND SAGITTAL PLANE KNEE BIOMECHANICS IN RECUMBENT CYCILING ....................... 30 Abstract ................................................................................................................................ 30 Introduction .......................................................................................................................... 31 Method ................................................................................................................................. 33 Participants ....................................................................................................................... 33 Instrumentation ................................................................................................................. 34 Procedures ........................................................................................................................ 35 Data and Statistical Analysis ............................................................................................. 35 Results .................................................................................................................................. 37 Discussion............................................................................................................................. 38 Conclusion ............................................................................................................................ 43 LIST OF REFERENCES .........................................................................................................
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