i The Systemic Myokine Response to an Acute Bout of Blood Flow Restricted Exercise by Eric M ...

145 Pages·2017·4.25 MB·English

by  Eric Bugera

i

The Systemic Myokine Response to an Acute Bout of Blood Flow Restricted Exercise
by
Eric M. Bugera

A thesis submitted to the Faculty of Graduate Studies of
The University of Manitoba
in partial fulfilment of the requirements for the degree of
MASTER OF SCIENCE

Faculty of Kinesiology and Recreation Management
University of Manitoba
Winnipeg

Copyright 2017 © Eric M. Bugera
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ABSTRACT
Blood flow restricted resistance training (BFR-RT) is an emerging hypertrophy training
modality. A complete profile of its mechanisms of action has yet to be elucidated. Cytokines are
universal intercellular messengers. Recent research has begun to implicate certain cytokines
(termed “myokines”) in skeletal muscle hypertrophy pathways; however, no research has been
conducted on the systemic myokine response to BFR-RT. The appearance of systemic myokines
interleukin-6 (IL-6), interleukin-15 (IL-15), and decorin were measured following acute bouts of
low-intensity resistance training (LI-RT), BFR-RT, and high-intensity resistance training (HI-
RT) in young males to determine if BFR-RT modifies the exercise-induced systemic myokine
response. No measureable levels of IL-6 were observed during the project. No significant effects
were observed for IL-15. A significant time but no condition or condition by time effect was
observed for decorin. These findings suggest that BFR-RT does not modify the systemic
myokine appearance of IL-6, IL-15, or decorin.
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ACKNOWLEDGEMENTS
It’s important that I acknowledge the tremendous support and encouragement I’ve
received while completing this program. The challenges and successes I’ve experienced over the
last two years would not have been as meaningful without these individuals.
First and foremost I would acknowledge the efforts of my academic advisor Dr. Stephen
Cornish. Thank you for not only planting the seed to challenge myself with graduate school but
also for your continued mentorship over the course of this two year whirlwind. While it seemed
like fires would start at every turn, we successfully maneuvered through it all unscathed. Further,
I would thank my committee members Dr. Todd Duhamel and Dr. Jason Peeler for their
critiques, insights, and dedication to guiding my progress. Your contributions have all been
invaluable to my education.
Similarly, I would like to acknowledge my cohort members Tim Beaver and David
Turczyn. The experiences we shared during our coursework are the foundation with which this
project is based.
I humbly thank my participants and phlebotomists for their efforts throughout this
project. None of you could have been more forthcoming and pleasant to work with.
I would like to specifically acknowledge the contributions of Jérémie Chase, Mark
Pinder, and Tanya Podilchak. In many ways Jérémie acted as a co-advisor to Dr. Cornish.
Jérémie provided critical insights and experiences at every step for which I may never be able to
adequately repay him. Mark has been an irreplaceable mentor and friend as we traversed
(commiserated) through our programs, may this bond continue throughout life my friend.
Finally, Tanya has provided a fresh perspective and in many ways mirrors my own experiences
through graduate school thus far. She is a constant reminder of my own trials and tribulations,
but also my commitment to finishing the job right.
I must also thank my family for their continuous support throughout every challenge I
undertake. Your constant presence provides me the confidence and ambition to better myself.
Further, to my extended family and friends, I apologize for my absence during times which
required an extremely narrow focus on success. Although unspoken, your understanding meant
everything.
Finally, to my beautiful girlfriend Victoria. You are the sole person to have experienced
every step of this program alongside me. Words would never do justice to the emotion evoked
reminiscing our shared experiences during these last two years. Simply, you are the reason for
my success. I love you. May we conquer all of life’s adventures together.
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TABLE OF CONTENTS
TITLE................................................................................................................................................i
ABSTRACT..................................................................................................................................... ii
ACKNOWLEDGEMENTS ............................................................................................................ iii
TABLE OF CONTENTS................................................................................................................ iv
LIST OF TABLES ......................................................................................................................... vii
LIST OF FIGURES ...................................................................................................................... viii
LIST OF APPENDICES ................................................................................................................. ix
CHAPTER 1 – SCIENTIFIC FRAMEWORK ............................................................................... 1
1.1 Introduction ...................................................................................................................... 1
1.2 Review of Literature.............................................................................................................. 4
1.2.1 Blood Flow Restriction Training .................................................................................... 4
1.2.2 Proposed BFR-RT Mechanisms of Action......................................................................... 4
1.2.3 BFR-RT Safety Considerations .................................................................................... 14
1.2.4 Cytokines and Myokines .............................................................................................. 19
1.2.5 Interleukin-6 ................................................................................................................. 20
1.2.6 Interleukin-15 ............................................................................................................... 24
1.2.7 Decorin ......................................................................................................................... 26
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1.3 Statement of Problem .......................................................................................................... 27
1.4 Hypotheses .......................................................................................................................... 28
CHAPTER 2 – METHODS .......................................................................................................... 30
2.1 Participants .......................................................................................................................... 30
2.1.1 Sample Size Calculation ............................................................................................... 30
2.1.2 Inclusion and Exclusion Criteria .................................................................................. 31
2.2 Procedures ........................................................................................................................... 32
2.2.1 Blood Flow Restriction via KAATSU.......................................................................... 33
2.2.2 Familiarization and 1RM Testing ................................................................................. 33
2.2.3 Resistance Training Bouts ............................................................................................ 35
2.2.4 Blood Sampling and Analysis ...................................................................................... 38
2.2.5 Dietary Tracking ........................................................................................................... 39
2.3 Statistical Analysis .............................................................................................................. 41
CHAPTER 3 – RESULTS ............................................................................................................ 42
3.1 Participant Characteristics ................................................................................................... 42
3.2 Exercise Interventions ......................................................................................................... 43
3.3 Blood Analysis Results ....................................................................................................... 43
CHAPTER 4 – DISCUSSION ...................................................................................................... 48
4.1 Interleukin-6 ........................................................................................................................ 49
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4.2 Interleukin-15 ...................................................................................................................... 52
4.3 Decorin ................................................................................................................................ 55
4.4 Study Limitations ................................................................................................................ 58
CHAPTER 5 – CONCLUSION.................................................................................................... 61
5.1 Implications for Future Research ........................................................................................ 61
REFERENCES ............................................................................................................................. 63
APPENDICES .............................................................................................................................. 77
vii

LIST OF TABLES
Table 1.1 Summary of BFR-RT Hypertrophy Research ................................................................ 3
Table 1.2 Plasma IL-6 Responses to Various Exercise ................................................................ 23
Table 1.3 Plasma IL-15 Responses to Various Exercise .............................................................. 25
Table 1.4 Plasma Decorin Response to Resistance Exercise........................................................ 27
Table 2.1 Exercise Intervention Details ........................................................................................ 35
Table 3.1 Participant Descriptive Characteristics ......................................................................... 42
Table 3.2 Numerical Data for Systemic Myokine Concentrations ............................................... 46
viii

LIST OF FIGURES
Figure 2.1 Visual Depiction of Blood Flow Restricted Knee Extensions via KAATSU ............. 32
Figure 2.2 Timeline of Participant Intervention ........................................................................... 36
Figure 2.3 Timeline of One Study Arm ........................................................................................ 38
Figure 3.1 Plasma Interleukin-15 Concentrations ........................................................................ 44
Figure 3.2 Plasma Decorin Concentrations .................................................................................. 45
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LIST OF APPENDICES
APPENDIX A – Comparison of Hormones and Myokines.......................................................... 78
APPENDIX B – Myokine Research Summary ............................................................................ 80
APPENDIX C – PAR-Q+ ............................................................................................................. 88
APPENDIX D – Anti-Inflammatory Guide.................................................................................. 93
APPENDIX E – Dietary Intake Log ............................................................................................. 95
APPENDIX F – NSCA 1RM Test Protocol ............................................................................... 105
APPENDIX G – Ethics Approval Certificate ............................................................................. 107
APPENDIX H – Informed Consent ............................................................................................ 109
APPENDIX I – ELISA Information ........................................................................................... 117
APPENDIX J –Plasma Myokine Concentration Data ................................................................ 130
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CHAPTER 1 – SCIENTIFIC FRAMEWORK
1.1 Introduction
Resistance training designed with the goal of enhancing skeletal muscle hypertrophy has evolved
to include many unique exercise techniques. Each particular protocol may present the user with
varying degrees of training stimuli such as mechanical tension, metabolic stress, or muscle
damage which results in skeletal muscle adaptation (Schoenfeld, 2010). While these three stimuli
appear to initiate skeletal muscle hypertrophy pathways, many underlying mechanisms which
ultimately produce the hypertrophic adaptations have since been detailed. Stimulation of
myogenic pathways, endocrine influence, and myogenic stem cells may all provide unique
contributions to skeletal muscle hypertrophy (Schoenfeld, 2010); however, recent research has
also identified a potential role for myokines in this process as well (Pedersen, 2011; So, Kim,
Kim, & Song, 2014).
One particular training method receiving greater research interest is blood flow restricted
resistance training (BFR-RT). BFR-RT can be described as applying a pressurized cuff around
the most proximal portion of an exercising limb (arm or leg), inflating the cuff to a
predetermined occlusive pressure such that venous return is restricted while arterial flow is
unimpeded, and completing a low load, high repetition, low rest period training protocol under
the condition of mild vascular restriction (Pope, Willardson, & Schoenfeld, 2013).
An interesting dichotomy then arises between typically prescribed exercise parameters designed
to elicit skeletal muscle hypertrophy and BFR-RT techniques. Standard exercise parameters
designed to elicit muscular hypertrophy in novice to intermediate trainees includes loading