Ithaca College Digital Commons @ IC Ithaca College Theses 2019 Power Characteristics of Conventional and Hexagonal Barbell Jump Squats Josh Kieffer Follow this and additional works at: https://digitalcommons.ithaca.edu/ic_theses Part of the Exercise Science Commons POWER CHARACTERISTICS OF CONVENTIONAL AND HEXAGONAL BARBELL JUMP SQUATS A Masters Thesis presented to the Faculty of the Graduate Program in Exercise and Sport Sciences Ithaca College __________________ In partial fulfillment of the requirements for the degree Master of Science __________________ by Josh Kieffer August 2019 Ithaca College School of Health Sciences and Human Performance Ithaca, New York CERTIFICATE OF APPROVAL __________________ MASTER OF SCIENCE THESIS __________________ This is to certify that the Thesis of Josh Kieffer submitted in partial fulfillment of the requirements for the degree of Master of Science in the School of Health Sciences and Human Performance at Ithaca College has been approved. Thesis Adviser: ________________________________________________ Committee Member: ________________________________________________ Candidate: ________________________________________________ Chair, Graduate Program: ________________________________________________ Dean of Graduate Studies: ________________________________________________ Date: ________________________________________________ ABSTRACT Training to develop power typically involves performing a combination of slow-moving resistance exercises against heavy loads (e.g., back squats) and/or fast-moving exercises against light loads (e.g., jump squats). Hexagonal barbell exercises such as hexagonal barbell deadlift (HBD) and hexagobal barbell jump squats (HBJS) are commonly used alternatives to conventional barbell exercises such as the back squat (BS) and jump squat. The change in load position with these hexagonal barbell exercises appears to allow for greater force, velocity, and power compared to conventional barbell exercises, however knowledge on hexagonal barbell exercises is limited by lack of studies. The current study examined differences in maximum strength between BS and HBD and differences in power characteristics between BJS and HBJS. Twelve resistance trained individuals (9 male, 3 female) volunteered to participate. Participants performed one-repetition maximum (1RM) strength testing in the BS and HBD. Participants also completed loaded jump testing with BJS and HBJS at 0, 10, 20, 30, 40, and 50% 1RM. Jump height and peak power (PP) were measured using a linear position transducer (GymAware, Kinetics, Canberra, ACT). Results showed participants lifted significantly greater 1RM loads using the HBD relative to BS (p < .05). Peak power was greatest for both BJS and HBJS at 0% 1RM. There were no differences in PP between barbell conditions across the six relative loads despite HBJS being performed at greater absolute loads. Analysis of F-v characteristics showed participants demonstrated greater maximum power and maximum force under HBJS compared to BJS conditions (p < .05). The results suggest that HBD and HBJS may provide adequate alternatives to BS and BJS exercises but these alternatives may be more force iii dominant and provide a greater stimulus for training maximum power. Future research should examine differences in training adaptations for these exercises. iv ACKNOWLEDGMENTS I would like to thank my thesis advisors Dr. Sforzo and Dr. Diggin for their support, guidance, and for challenging me throughout this project. Thank you to all of my participants for volunteering your time and effort to be in this study. Thank you to my family for your constant encouragement while I pursue my dreams. And lastly, thank you to my friends at Ithaca College for sharing in my struggles, helping me grow as a person, and making these past two years a great experience. v TABLE OF CONTENTS ABSTRACT ....................................................................................................................... iii ACKNOWLEDGMENTS .................................................................................................. v LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES ............................................................................................................ x Chapter 1. INTRODUCTION ...........................................................................................................1 Statement of Purpose .................................................................................................. 3 Hypotheses .................................................................................................................. 3 Assumptions of the Study ........................................................................................... 4 Definition of Terms..................................................................................................... 4 Delimitations ............................................................................................................... 6 Limitations .................................................................................................................. 6 Summary ..................................................................................................................... 6 2. REVIEW OF LITERATURE ..........................................................................................8 Introduction ................................................................................................................. 8 Power and Athletic Performance ................................................................................ 8 Defining Power ......................................................................................................... 12 Training for Power .................................................................................................... 13 Converting Strength to Power ............................................................................... 16 vi Optimal Loading for Pmax ...................................................................................... 18 F-v Profiling .............................................................................................................. 22 Summary ................................................................................................................... 24 3. METHODS ................................................................................................................... 26 Participant Characteristics ........................................................................................ 26 Experimental Procedures .......................................................................................... 26 Maximum Strength Testing ...................................................................................... 27 F-v Jump Testing ...................................................................................................... 28 Statistical Analysis .................................................................................................... 30 4. RESULTS ..................................................................................................................... 31 Maximum Strength ................................................................................................... 31 Peak Power Output ................................................................................................... 32 Force-Velocity Profile Comparison .......................................................................... 34 Summary ................................................................................................................... 35 5. DISCUSSION ............................................................................................................... 37 Limitations ................................................................................................................ 42 Practical Implications................................................................................................ 44 Summary ................................................................................................................... 45 6. SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS ............................... 46 Summary ................................................................................................................... 46 vii Conclusions ............................................................................................................... 47 Recommendations ..................................................................................................... 47 REFERENCES ................................................................................................................. 49 APPENDICES .................................................................................................................. 58 A. Informed Consent Form ............................................................................................58 B. Health Screening Questionnaire ................................................................................64 C. Raw Data Key ...........................................................................................................68 D. Raw Data ...................................................................................................................70 viii LIST OF TABLES Table Page 1. Back Squat