MAKING THE CUT:

NUTRITION, HYDRATION, & PERFORMANCE IN COMBAT SPORTS

A Dissertation

presented in partial fulfillment of requirements

for the degree of Doctor of Philosophy

in the Department of Nutrition and Hospitality Management

The University of Mississippi

By

KATHARINE L. HALFACRE

May 2020
 ProQuest Number: 27959485

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 ABSTRACT

This study investigated nutrition, hydration, supplementation, and body composition in

relation to performance among mixed martial arts athletes practicing rapid weight loss. Mixed

martial arts athletes practice intentional dehydration and nutritional fasting to achieve rapid

weight loss, a practice that can damage health and performance. Male mixed martial arts athletes

practicing rapid weight loss participated in the study during a week of competition which was

not the same for all athletes. Food/activity journals were collected to assess nutrition, fasting, and

supplementation. Urine specific gravity was assessed at baseline, weigh-ins, and endpoint. Body

composition and punch velocity were assessed at baseline and endpoint. Competition result and

self-rated performance data were also recorded. Descriptive statistics, Pearson correlations,

ANOVA, and t-tests were utilized to determine the significance of relationships between

variables. Of the participants who completed the study, eight (88.9%) were dehydrated at the

official weigh-ins to qualify for competition, with one (11.1%) failing to achieve euhydration

prior to competition. Among the sample of nine mixed martial arts athletes, significant weight

loss was observed (M=14.54 lb, SD=4.21 lb). Changes in punching velocity were negatively

correlated with fasting duration (r=-0.763, p<.05). Self-rated performance was positively

correlated with changes in punching velocity (r=0.676, p<.05) and negatively correlated with

endpoint USG (r=-0.678, p<.05). These findings suggest shorter fasting periods may be

ii
beneficial to combat sports athletes practicing rapid weight loss. However, a study of these

factors across a larger sample is warranted before drawing definitive conclusions.

iii
 DEDICATION

I dedicate this dissertation to my daughter Scarlett, may you be strong, brave, and unique.

I cannot wait to meet you.

To my husband, Mykel, for his unwavering support, positivity, and wonderful skills at

brewing coffee and mixing cocktails, I dedicate this dissertation to you.

I also dedicate this research to the combat sports fighters of the past, present, and future.

This research honors the sacrifices you make in your pursuit for greatness.

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 LIST OF ABBREVIATIONS AND SYMBOLS

ABC Association of Boxing Commissions and Combative Sports

AF Activity factor

ALEA Acute Low Energy Availability

AMPK AMP-activated protein kinase

BF% Body fat percentage

BMR Basal metabolic rate

BW Body weight

CLA Conjugated linoleic acid

CSAC California State Athletic Commission

DHA Docosahexaenoic acid

EEE Exercise energy expenditure

EPA Eicosapentaenoic acid

FFA Free fatty acids

FFM Fat-free mass

IOC International Olympic Committee

ISAK International Society for the Advancement of Kinanthropometry

LEA Low Energy Availability

MMA Mixed Martial Arts

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NCAA National Collegiate Athletic Association

NDSR Nutritional Data System for Research

RED-S Relative energy deficiency in sport

RWL Rapid weight loss

TEA Total energy availability

TEE Total energy expenditure

TEF Thermic effect of food

TKD Taekwondo

URTI Upper respiratory tract infection

USG Urine specific gravity

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 ACKNOWLEDGEMENTS

The guidance and support of Dr. Kathy Knight, Dr. Melinda Valliant, Dr. David Joung,

and Dr. Martha Bass were vital in the formulation, execution, and reporting of this research

project. I am very grateful for their contributions.

Dr. Knight, I could not imagine going through this process with anyone else. You were

an extremely supportive supervisor, and I sincerely appreciate your willingness to offer your

wisdom while providing me absolute freedom to research a niche topic that was important to me.

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 TABLE OF CONTENTS

ABSTRACT………………………………………………………………………………………ii

DEDICATION……………………………………………………………………………………iv

LIST OF ABBREVIATIONS AND SYMBOLS………………………………………………....v

ACKNOWLEDGEMENTS……………………………………………………………………...vii

LIST OF TABLES……………………………………………..……………………………...….ix

CHAPTER I: INTRODUCTION………………………………………………………………….1

CHAPTER 2: REVIEW OF LITERATURE…………………………………………...…………3

CHAPTER 3: METHODS……………………………………………………...………………..22

CHAPTER 4: RESULTS……………………………………………………………………..….31

CHAPTER 5: DISCUSSION……………………………………………………….……………46

BIBLIOGRAPHY………………………………………………………………………………..59

LIST OF APPENDICES…………………………………………………………………………97

VITA……………………………………………………………………………………………106

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 LIST OF TABLES

1. VARIABLE DEFINITIONS AND MEASUREMENTS………………………...…….……29

2. HYPOTHESES AND STATISTICAL ANALYSIS…………………………………..…….30

3. SAMPLE CHARACTERISTICS AT VARIOUS STAGES OF RAPID WEIGHT LOSS....32

4. FREQUENCIES FOR RAPID WEIGHT LOSS PARAMETER AMONG MMA

ATHLETES………………………………………………………………………………….34

5. ONE-WAY ANOVA FOR CHANGES IN BODY COMPOSITION DURING RWL……..37

6. PEARSON’S R: NUTRITION, HYDRATION, BODY COMPOSITION,

SUPPLEMENTATION, & PERFORMANCE………………………………………………40

7. INDEPENDENT-SAMPLES T-TESTS FOR IMPROVED PUNCHING VELOCITY…....43

8. INDEPENDENT-SAMPLES T-TESTS FOR SELF-RATED PERFORMANCE………….45

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 CHAPTER 1

INTRODUCTION

Combat sports competitions, which include boxing, kickboxing, wrestling, judo, jujitsu,

karate, taekwondo (TKD), and mixed martial arts (MMA), are often separated into weight

divisions to promote fairness in competition. However, this encourages fighters to attempt to

gain a competitive edge through rapid weight loss (RWL) and refeeding, a practice that involves

voluntary dehydration, fasting, and other behavioral strategies aimed at achieving significant

weight loss prior to qualifying for weight-class competition (Brito et al., 2012; Coswig, Fukuda,

& Vecchio, 2015; Fleming & Costarelli, 2007; Langan-Evans, Close, & Morton, 2011; Matthews

& Nicholas, 2016; Pallares et al., 2016; Pettersson, Eckstrom, & Berg, 2012; Pettersson,

Ekstrom, & Berg, 2013; Reljic et al., 2015; Timpmann, Oopik, Paasuke, Medijainen, & Ereline,

2008). RWL is common among combat sports athletes of all age groups (Brito et al., 2012).

Though, the safety of RWL among this population is unclear and yet to be placed under

scientific scrutiny, the practice has been linked to hospitalization (Carroll, 2018; MMANewPL,

2017) and death (Cruz, 2013; Rondina, 2017; Zidan, 2014).

Fighters modify their nutrition, hydration, and behavior during training to “make weight,”

the process of achieving enough weight loss to compete in a lighter weight class. Despite its

seeming importance, there appears to be no consensus opinion on which nutritional strategies

produce the best results for health and performance. Hydration is central to the RWL and

refeeding process, and athletes practice several different strategies to lose water weight,

1
including but not limited to the use of diuretics and saunas, as well as exercising in sauna suits

(Brito et al., 2012; Franchini et al., 2012; Matthews & Nicholas, 2016), to remove large amounts

of body water through perspiration and urine in order to make weight. These practices, as well as

the general practice of RWL, present risks and rewards for combat sports athletes seeking a

competitive edge. This analysis aims to identify the nutritional and behavioral practices utilized

by combat sports athletes in order to “make the cut,” achieving a weigh-in weight that does not

exceed the maximum allowable weight in their weight class. It is also important to identify the

consequences of this practice on the physical and cognitive ability of combat sports athletes.

Research Objectives and Specific Questions

The purpose of this study is to analyze how hydration, nutrition, dietary supplementation,

and body composition are associated with athletic performance among MMA athletes practicing

RWL. This research aims to answer these specific questions:

1. What is the status of MMA fighters pertaining to dehydration, acute energy availability,

dietary supplementation, and body composition at different stages of combat preparation?

2. What associations exist between hydration, nutrition, dietary supplementation, and acute

changes to weight and body composition among MMA fighters?

3. Are changes in performance after refeeding correlated with acute body composition

changes, nutrition, and hydration status among MMA fighters?

4. How are hydration, acute energy availability, dietary supplementation, and acute changes

in weight and body composition related to objective and perceived performance among

MMA fighters?

2
 CHAPTER 2

REVIEW OF LITERATURE

Although RWL and refeeding to quickly regain weight are familiar practices among

combat sports athletes of all age groups (Brito et al., 2012), the practice has been linked to

hospitalization (Carroll, 2018; MMANewPL, 2017) and death (Cruz, 2013; Rondina, 2017;

Zidan, 2014), results that are increasing as combat sports, particularly MMA, have become more

popular. This review highlights existing literature regarding hydration, nutrition, and dietary

supplementation among combat sports athletes, identifying topics which may deserve more

attention from empirical studies.

Hydration

Intentional water restriction is a very common practice among combat sports athletes

practicing RWL (Hoffman & Maresh, 2011). Additionally, several studies have found that many

combat sports athletes, at various levels of competition, are inadequately hydrated (Fleming &

Costarelli, 2007; Matthews & Nicholas, 2016; Pallares et al., 2016; Pettersson & Berg, 2014).

Researchers have observed dehydration’s association with impaired physical (Cheuvront, Carter,

Montain, & Sawka, 2004; Nielsen et al., 1981) and cognitive (Edwards et al., 2007; Wilson &

Morley, 2003) functions. Physical traits such as heart rate and body temperature significantly

increase among dehydrated athletes competing in high-intensity activities (Maughan, 2003).

Dehydration prior to exercise has an observed association with higher self-reported fatigue as

well as the incidence and severity of concussions and associated symptoms (Patel, Mihalik,

3
Notebaert, Guskiewicz, & Prentice, 2007). Dehydration may also have a confounding influence

on the clinical measures of baseline concussion tests (Weber et al., 2013). Intentional

dehydration appears to warrant additional attention from athletes, coaches, policymakers, and

other stakeholders who may influence guidelines and reduce exposure to the risks of intentional

dehydration.

In 2017, the National Collegiate Athletic Association (NCAA) set several standards and

regulations pertaining to the weight of collegiate wrestlers and the practice of RWL (National

Collegiate Athletic Association, 2017). According to these NCAA guidelines, urine specific

gravity (USG) should be utilized as a screening for qualification to weigh-in prior to wrestling

competition. Currently, collegiate wrestlers are required to determine hydrated weight through a

measurement of weight and urine specific gravity. In doing so, collegiate wrestlers are required

to be present for weight measurements and to provide urine samples to be analyzed using a

digital refractometer, providing an assessment of hydration status based on USG. A measurement

of body mass taken with an accompanying urine specific gravity of less than or equal to 1.020 is

considered a valid hydrated weight. Once hydration weight has been determined, body fat

percentage is calculated using skin-fold measurements, hydrostatic weighing, or

plethysmography analysis using a Bod PodTM (COSMED, Rome, Italy). From this, the

wrestler’s weight at 5% body fat is calculated. After body fat has been determined, the final

determination of minimum wrestling weight is determined by comparing the outcomes of two

methods. The first method estimates the wrestlers weight at 5% body fat, holding other factors

constant. The second method allows for a reduction of 1.5% body weight (BW) each week prior

to competition; this is estimated with the equation: BW – (0.015/7 × number of days until

4
competition × BW) = minimum BW. Once the two estimations of lowest allowable weight are

calculated, the athlete’s minimum wrestling weight is always the higher of the two values.

In 2017, the California State Athletic Commission (CSAC) passed the most stringent

restrictions, to-date, on RWL among MMA athletes in the United States (Raimondi, 2017).

Although several components of the CSAC’s 10-point plan dealt with the financial aspect of the

sport, two key points were aimed at addressing the risks of RWL among MMA athletes

competing under the CSAC’s jurisdiction. First, additional weight divisions for MMA

competitions sanctioned by the CSAC were created at the 165, 175, 195, and 225-pound levels.

Previously, weight divisions existed at the 115, 125, 135, 145, 155, 170, 185, 205, and 265-

pound levels, leaving 15+ lb gaps between some weight divisions. Despite fitting closely

between the newly created weight-divisions, the CSAC did not vote to eliminate the 170-pound

weight division after considering its significance in the history of MMA in the United States. The

170-pound “welterweight” division has featured popular mixed martial artists such as Pat

Miletich, Matt Hughes, B.J. Penn, Georges St-Pierre, Robbie Lawler, Johnny Hendricks, and

Tyron Woodley, giving it a prominent place in the history of the sport for its role in the growth in

the sport’s popularity in the United States. Additionally, the new regulations allow for MMA

athletes competing in CSAC-sanctioned competitions to regain no more than 10% of his or her

body weight between weigh-in and fight-day weight checks. In reaction to the passing of these

CSAC regulations, the Association of Boxing Commissions and Combative Sports (ABC)

adopted 165, 175, 195, and 225 weight divisions under the unified rules for MMA (Marrocco,

2017). The ABC did not adopt the 10% limit on regained weight that was within the CSAC

regulations.

5
 Previous research has identified mild dehydration at a decrease of 1-2% body weight

(Parrish, Valliant, Knight, & Bass, 2018), a threshold associated with impaired athletic ability

(Cheuvront et al., 2004; Nielsen et al., 1981) and cognitive function (Edwards et al., 2007;

Wilson & Morley, 2003). Therefore, the restrictions placed on MMA athletes under the 10-point

CSAC plan may not be effective in eliminating all the detrimental effects of intentional

dehydration during RWL. Studies among this population have observed sample weight-cuts as

low as 2.3% body mass (Reale et al., 2016) and as high as 10.0% (Coswig, Fukuda, & Vecchio,

2015), among both male and female athletes (Fleming & Costarelli, 2007; Matthews & Nicholas,

2016; Timpmann et al., 2008). It is important to note that the Coswig, Fukuda, & Vecchio (2015)

and the Matthews & Nicholas (2016) studies were the only two found through this review which

assessed the RWL practice of MMA athletes. These samples also displayed the greatest observed

values for percentage of body mass reduction through RWL (Coswig et al., 2015; Matthews &

Nicholas, 2016), suggesting that MMA athletes may undergo extreme RWL compared to other

combat sports athletes. The place of RWL in combat sports culture, particularly its nearly-

universal practice among MMA fighters (Hillier et al., 2019), combined with potentially

inadequate regulations, may put combat sports athletes at serious risk for health and performance

issues as a result of intentional dehydration during RWL.

The metabolic implications of dehydration have been thoroughly documented as several

animal studies have found an association between hydration and muscle glycogen uptake (Low,

Rennie, & Taylor, 1996; Neufer et al., 1991; Waller, Heigenhauser, Geor, Spriet, & Lindinger,

2009). While Fernández-Elías, Ortega, Nelson, & Mora-Rodriguez (2015) did not find a

relationship between muscle hydration and glycogen in male cyclists, their findings did not

oppose such a relationship either. Muscle glycogen is depleted through exercise, but 40% of the

6
expenditure can be restored after four hours with adequate carbohydrate intake (Ivy, Katz,

Cutler, Sherman, & Coyle, 1988; Ivy, Lee, Brozinick, & Reed, 1988). Muscle glycogen is stored

with water at a ratio of 1:3 (Fernández-Elías et al., 2015), highlighting the importance of

adequate hydration in order for optimization of energy availability during athletic performance.

However, despite the findings of muscular water-to-glycogen ratios as high as 17:1 by

Fernández-Elías et al. (2015), recent research has found that this excess water is not released

during exercise and utilized to rehydrate the body (King, Jones, & O’Hara, 2018). This suggests

that although dehydration could be detrimental to performance, intentional hyperhydration,

compared to euhydration, likely yields no additional benefits to glycogen storage within muscle

tissue. Due to the practice of dehydration during RWL, combat sports athletes could be training

and potentially competing with less than optimal glycogen stores within their muscle tissues.

In a study of hydration and protein metabolism, McCue, Sandoval, Beltran, & Gerson

(2017) observed increased rates of muscle catabolism in mice during times of low food intake

and dehydration. While this effect was not statistically significant and not as dramatic as similar

observations among birds (Gerson & Guglielmo, 2011), it does show that mammals increase

protein catabolism while dehydrated and fasting. The mechanism behind this metabolic shift is

likely due to the amount of water that is released as a result of protein catabolism, five times the

amount of water released during fat oxidation (Gerson & Guglielmo, 2011; Jenni & Jenni-

Eirmann, 1998). These processes may not be present in humans, and more research is needed to

explore the association between dehydration and increased protein catabolism. If this effect is

present among human subjects, then intentional dehydration during RWL cycles would directly

conflict with the aims of reducing fat mass while retaining lean mass prior to competition.

7
 Hydration and energy metabolism have been studied extensively for the past 20 years,

primarily with a focus on reducing the prevalence of obesity and other chronic illnesses.

Evidence of the role of hydration in nutrient metabolism among healthy men is fairly limited, but

findings suggest that dehydration, acute or chronic, could have undesirable effects on the

metabolism of combat sports athletes. Multiple studies have found individuals in a state of

hyper-hydration to experience protein-sparing effects compared to those in a dehydrated or

euhydrated state (Berneis, Ninnis, Haussinger, & Keller, 1999; Keller, Szinnai, Bilz, & Berneis,

2003). Additionally, lipolysis appears to be upregulated by higher intercellular hydration levels

(Achten & Jeukendrup, 2004; Berneis et al., 1999; Keller et al., 2003), independent of lipolysis-

regulating hormones (Bilz, Ninnis, & Keller, 1999). These findings suggest that the intentional

dehydration practices that combat sports fighters undergo may not be conducive to the retention

of lean mass and catabolism of fat mass during the fight week. Important considerations of

hydration, metabolism, lean-mass retention, and weight-loss goals should be made by fighters

and coaches during the fight-week weight cut; however, these associations are complex and are

not well-observed among this population.

The intentional dehydration practice of combat sports athletes is among the life-

threatening aspects of sport today. The risks of intentional dehydration in this family of sports is

apparent through its association with recent hospitalizations (Carroll, 2018; MMANewsPL,

2017) and deaths (Cruz, 2013; Rondina, 2017; Zidan, 2014). Specifically, these hospitalizations

and deaths have all been the result of acute changes in cardiac performance, which can cause

stroke, heart attack, cardiopulmonary failure, and sudden death. Scientific investigation of the

acute cardiac changes associated with RWL among combat sports athletes is scarce. Electrolyte

balance is a potential causal factor in this phenomenon as the Sodium-Potassium ATPase proton

8
pump (NA+ - K+ ATPase) sparks glycolysis and ATP production, particularly in neural tissue

(Armengaud et al., 2009; James et al., 1996; Raffin, Sick, & Rosenthal, 1988; Raffin, Rosenthal,

Busto, & Sick, 1992; Roberts, 1993). Because of Na+-K+ ATPase’s role in maintaining a stable

heartbeat (Karaki, Urakawa, & Kutsky, 1984; Pohl, Wheeler, Murray, 2013), excessive

dehydration could theoretically neutralize the electrical gradient across cellular membranes,

resulting in significant alterations to cardiac rhythm. We have yet to critically investigate how

hydration, nutrition, and dietary supplementation during the RWL cycles of combat sports

athletes affect cardiac function. Electrolytes have important implications for protein synthesis

(Canady, Ali-Osman, & Rubel, 1990; Cannon, Frazier, & Hughes, 1952; Cunningham &

Bridgers, 1970), bone health (Barzel, 1995; Green & Kleeman, 1991; Krieger, Frick, &

Bushinsky, 2004; Lemann, Litzow, & Lennon, 1966; Lemann, Bushinsky, & Hamm, 2003), and

metabolism (Armengaud et al., 2009; James et al., 1996; Raffin et al., 1988; Raffin et al., 1992;

Roberts, 1993). Yet, we know little of the how electrolyte levels fluctuate during the fight-week

RWL cycle commonly practiced in combat sports. Further research into the safety of RWL,

particularly intentional dehydration, may be instrumental in preventing death, hospitalization,

injury, and impaired performance among this population. Additionally, research efforts in this

subfield of nutrition could yield important information for combat sports athletes, coaches, and

administrators associated with combat sports that could shape the future of the sport to optimize

safety, health, and performance.

Nutrition

Due to the influence of carbohydrates, fats, proteins, vitamins, minerals, and water on

energy availability and health, it is essential that fighters consume of these nutrients to ensure

optimal performance during training and after the RWL-refeeding process. As mentioned

9
previously, water is especially important due to its involvement in transporting nutrients,

temperature regulation, and most other physiological processes of the human body. In addition to

intentional dehydration being the primary nutritional approach to RWL, research has identified

the widespread practice of limiting nutritional intake among judo (Artioli et al., 2010), boxing

(Hall & Lane, 2001; Morton, Robertson, Sutton, & MacLaren, 2010), taekwondo (Fleming &

Costarelli, 2007; Fleming & Costarelli, 2009), and wrestling competitors (Alderman, Landers,

Carlson, & Scott, 2004; Kininghamn & Gorenflo, 2001; Oppliger, Steen, & Scott, 2003). Other

studies have observed MMA fighters reducing nutritional intake significantly during RWL

cycles (Coswig et al., 2015; Matthews & Nicholas, 2016). Presently, the parameters which

combat sports athletes follow in regards to their nutrition during RWL are unclear.

Carbohydrates are the driving force behind anaerobic activity, the primary facilitator of

the intermittent skeletal movements in combat sports. Despite the importance of carbohydrates in

fueling relevant muscle contractions and the limited amount of carbohydrate storage available,

many fighters choose to reduce carbohydrates during RWL (Fleming & Costarelli, 2007;

Pettersson & Berg, 2014; Reljic et al., 2015). By reducing glycogen stores, the capacity for

anaerobic respiration during training is impaired. Though, fighters accept that risk with the aim

of reloading glycogen stores with carbohydrate consumption between weigh-in and competition,

often by consuming carbohydrate-rich drinks (Pettersson & Berg, 2014). By utilizing this

practice of carbohydrate loading prior to competition, fighters limit their ability to oxidize lipids

during activity (Langan-Evans et al., 2011). This limitation is the result of insulin secretions in

response to carbohydrate-rich foods and beverages, a detriment to lipolysis (Horowitz, Mora-

Rodriguez, Byerley, & Coyle, 1997). Additionally, this slowing of lipolysis may last for up to

four hours after a meal (Montain, Hopper, Coggan, & Coyle, 1991). Research has suggested that

10
an effectively-timed meal that is high in carbohydrates, with a lower glycemic impact, will not

attenuate lipolysis to the same degree as foods with higher glycemic impacts (Wee, Williams,

Tsintzas, & Boobis, 2005). While providing adequate glycogen stores should be a priority for

combat sports athletes who will require significant energy through glycolysis and the lactic acid

cycle, it is important that fighters and coaches are well-educated on the importance of priming

additional fuel systems such as the Kreb’s Cycle by promoting lipolysis. The popularity of

carbohydrate-rich drinks among combat sports athletes was observed by Petterson & Berg (2014)

and suggests that fighters and coaches are not effective in fueling the multiple energy systems

that will be relied on during the high-intensity, intermittent activities involved in martial arts

competition. According to current research, both athletes and their coaches may lack the

necessary nutritional understanding to ensure adequate fueling for training, and particularly

competition after RWL.

Dietary protein provides the body’s building blocks for muscle synthesis. Under ideal

conditions, protein would never be a primary source for energy during activity. This presents one

of the primary nutritional concern for combat sports athletes practicing RWL, the need for

protein. Fighters may need as much as 3 or 4 times more dietary protein compared to the average

person (Hoffman, 2002). Daily protein consumption at 0.8 – 1.0 g/kg body weight is needed for

the maintenance of adequate nitrogen balance, facilitation of muscle synthesis, and improvement

of muscular strength under stress (Hoffman et al., 2009; Lemon, Tornopolsky, Macdougal, &

Atkinson, 1992). The Academy of Nutrition and Dietetics suggests that athletes consume

between 1.2 – 2.0 g/kg body weight of protein each day, consistent with the demands of their

training sessions (Academy of Nutrition and Dietetics, American College of Sports Medicine,

and Dietitians of Canada, 2016; Campbell et al., 2007). For additional strength benefits, it has

11
been suggested that power athletes consume more than 2.0 g/kg protein each day (Hoffman,

Ratamess, Kang, Falvo, & Faigenbaum, 2006). This high requirement for protein presents a

complicated situation for combat sports athletes practicing RWL as they seek to maintain lean

mass while reducing their body mass, sometimes by more than 15% during the week of

competition.

Increased protein consumption makes it difficult to restrict caloric intake; however, it is

necessary to prevent the degradation of lean mass. Moreover, RWL often requires extreme

caloric restriction, such that competitors cannot meet protein requirements. Despite adaptations

to preserve body proteins during prolonged fasting (Cahill, 1970; Saudek & Felig, 1976),

previous studies have observed that long fasting periods result in muscle loss (Fryburg, Barrett,

Louard, & Gelfand, 1990; Nair, Woolf, Welle, & Matthews, 1987; Pozefsky, Tancredi, Moxley,

Dupre, & Tobin, 1976) as proteins are catabolized and mobilized to fuel gluconeogenesis in the

liver. This adaptation to low energy availability is signaled by reduced insulin and the increased

presence of glucocorticoids (Kettelhut, Pepato, Migliorini, Medina, & Goldberg, 1994).

Starvation conditions result in the signaling of atrogenes which rapidly mobilize proteins for

breakdown (Lecker et al., 2004); though the atrogene responses to starvation can vary by muscle

fiber type (Moriscot et al., 2010). Research has observed that protein breakdown to fuel

gluconeogenesis during fasting is more pronounced in the fast-twitch muscle fibers that athletes

rely on for explosive movements (Li & Goldberg, 2006). While athletes regularly practice

fasting to an extent that mobilizes large amounts of protein tissue for gluconeogenesis, scientific

evidence suggests that training can attenuate protein metabolism and promote lipolysis to fuel

gluconeogenesis and the Kreb’s Cycle (Gudiksen et al., 2018). Though, this may aid athletes in

lean-mass retention during RWL, there is no cessation of protein metabolism during the extended

12
fasting state that many combat athletes experience during RWL. Though combat sports athletes

typically experience fasting periods much shorter than the 60+ hour fasting periods associated

with observed muscle loss, little is known of its role in predicting health and performance

outcomes among this population.

The literature indicates that dietary fat may be the prioritized source of energy for the

fighter utilizing a low-carbohydrate, protein-rich diet. Fatty acids can be metabolized for energy

at light and moderate intensities of activity (Hoffman & Maresh, 2011). As glycogen stores are

depleted, fat takes over as the primary source for energy throughout the remainder of an activity

session (Hoffman, 2002). Assuming the intensity of training does not exceed the fueling ability

of fat, the primary difficulty with dietary approaches that prioritize fat and protein over

carbohydrate, for fighters, is that they must “prime” their bodies for fat oxidation throughout the

day (Langan-Evans et al., 2011) in order to reduce the impact of the insulin response on

lipolysis. This can be accomplished by spreading out the training sessions across the day to

balance the utilization of macronutrients (Langan-Evans et al., 2011). The case-study by Morton

et al. (2010) found that a professional boxer could have success with a carbohydrate-restricting

diet while having a morning running session, a pre-lunch technical session, and a final session

focused on strength and conditioning in the early evening. This practice has scientific merit as a

means to prime the body for fat oxidation by avoiding the lipolysis-slowing effects of

carbohydrate intake and the subsequent insulin response that lasts for hours (Montain et al.,

1991). However, researchers should seek a deeper understanding of the high-fat, low-

carbohydrate dietary approach and its effects on performance in training and competition among

this population.

13
 Regarding the metabolic importance of macronutrients, carbohydrate consumption is

necessary to produce and store glycogen needed for energy metabolism, particularly during

physical activity. Both insulin and endurance training stimulate the uptake of glucose by skeletal

muscle (Jensen, Rustad, Kolnes, & Lai, 2011). It is in the skeletal muscles where glucose is

primarily disposed, with 90% of the muscles’ glucose being stored as glycogen (Jue et al., 1989).

The importance of glycogen stores cannot be exaggerated in regards to athletic performance, as

glycolysis is the primary energy pathway for the movement of Type II, or slow twitch, muscle

fibers. By breaking down glycogen, these muscles are provided ATP needed for exercise;

however, these stores run out quickly which then places the burden of energy metabolism on free

glucose and free fatty acids (FFA) (Holloszy, Kohr, & Hansen, 1998). Additionally, the onset of

activity stimulates the process of glycolysis through the activation of several enzymatic pathways

(Greenberg, Jurczak, Danos, & Brady, 2005). As muscle contractions continue, glycogen stores

become depleted, resulting in the slowing of glycogen phosphorylase activity (Chasiotis, Sahlin,

& Hultman, 1983). While research does not agree on the importance of glucose uptake for all

populations, the review by Greenberg, Jurczak, Danos, & Brady (2005) indicates that, at high

intensities, an increased uptake of glucose is necessary for continued muscle contraction once

glycogen stores run out and lipolysis slows. The literature suggests that, through careful, well-

executed dietary glucose uptake, combat sports athletes could prime their bodies for

metabolizing FFAs by repeatedly depleting and limiting glycogen stores during training sessions

(Pilegaard et al., 2002). AMP-activated protein kinase (AMPK) is the enzyme that acts as the

primary force behind this shift from glycogenolysis to lipolysis during physical activity (Winder,

& Hardie, 1999). AMPK increases energy production while inhibiting the storage of muscular

glycogen. The regulation of energy metabolism by AMPK is activated as ATP is utilized and the

14
ratio of AMPK to ATP increases (Hardie, 2004). In addition to this, AMPK has been shown to

bind glycogen and is not affected by further addition of glycogen (Polekhina et al., 2003). This

allows the body to utilize extracellular glucose and FFA to produce energy through the activation

of translocation of the enzyme GLUT4, and the restriction of the limiting-enzyme, acetyl-CoA

carboxylase (Greenberg et al., 2005). These metabolic processes during high-intensity activity

highlight the importance of adequate energy availability at the time of competition in combative

sports.

In a consensus statement, the International Olympic Committee (IOC) listed male combat

sports athletes as a population at risk for relative energy deficiency in sport (RED-S) (Burke et

al., 2018; Mountjoy et al., 2018). Central to the IOC’s model of RED-S is chronic low energy

availability (LEA). LEA has significant biological impacts across many organ systems in both

sexes. However, the differences and similarities between the biological responses to chronic

LEA among male and female athletes is unknown (Loucks, 2007). While the intentional

dehydration practiced by combat sports athletes presents serious health concerns, chronic LEA

associated with RED-S presents a multitude of concerns for various body systems, specifically in

regards to the hormone testosterone (Hackney, Moore, & Brownlee, 2005; Hooper et al., 2017;

Tenforde, Barrack, Nattiv, & Fredericson, 2016). With targeted weight loss >10%, almost all

fighters would be classified as having acute LEA according to parameters suggested by previous

research (De Souza, et al., 2014). In the IOC’s Consensus Statement, a strong case is made for

the advancement of the scientific understanding of RED-S in various athlete populations due to

the metabolic, hematological, hormonal, cardiovascular, immunological, gastrointestinal, and

psychological constructs and consequences associated with the condition (Mountjoy et al., 2018).

Very little research has been conducted to include LEA, acute or chronic, and RED-S as they

15
relate to the various groups of combat sports athletes. Understanding the weight-management

practices and potential health and performance implications of combat sports athletes is crucial

to building our scientific body of knowledge on the subject.

The nutritional needs of the athlete in combat sports vary depending on the sport. For

instance, training needs will be very different for wrestlers as opposed to boxers. In theory, a

low-carbohydrate, high-protein diet with well-timed, calorically-balanced meals could be very

beneficial in priming these power athletes’ bodies for performance. The evidence, however,

indicates that combat sports athletes regularly consume diets that would not align with these

principles (Alderman et al., 2004; Artioli et al., 2010; Fleming & Costarelli, 2007; Fleming &

Costarelli, 2009; Coswig et al., 2015; Hall & Lane, 2001; Kininghamn & Gorenflo, 2001;

Matthews & Nicholas, 2016; Morton et al., 2010; Oppliger et al., 2003). Combat sports athletes

going through RWL are aiming to reduce body mass as much as possible, while also priming the

body for a high-intensity bout of activity. Herein lies the key nutritional dilemma faced by this

population, but they have coping strategies. There is a large body of evidence citing the use of

supplements among combat sports athletes. As indicated in the review by Langan-Evans et al.

(2011), the common supplements taken by athletes during RWL could be defined as either a

weight-loss supplement or an immune-boosting supplement. There is a large variance in the

amount of research and the validity of data regarding these supplements, as they relate to combat

sports athletes.

The most common weight-loss supplement used by combat sports athletes is caffeine

(Langan-Evans et al., 2011). Supplementation of caffeine has been associated with improved

metabolism during exercises of at least moderate intensity (Graham, 2001; Graham, Baltram,

Dela, El-Sohemy, & Thong, 2008; Ivy, J.L., Costill, Fink, & Lower, 1979; Maki et al., 2009;

16
Rains, Agarwal, & Maki, 2011; Venebles, Hulston, Cox, & Jeukendrup, 2008; Wetserterp-

Platenga, 2010). In addition to metabolic function, caffeine enhances weight loss through

thermogenic effects (Hursel & Wetserterp-Plantenga, 2010). Caffeine has an observed positive

effect on performance and energy availability (Davis & Green, 2009). A study by Santos et al.

(2014) found that caffeine supplementation of 5 mg/kg of body mass reduced reaction time in

combat sports athletes who were not fatigued. Additionally, caffeine supplementation of 3-5

mg/kg of body mass has improved intensity early in fights while also helping to maintain

intensity through successive bouts of competition among combat sports athletes (Diaz-Lara et al.,

2016; Santos et al., 2014). Risks associated with caffeine consumption include central nervous

system responses resulting in anxiety, dependency, and withdrawal (Burke, 2008; Jenkinson &

Harbert, 2008; Tunnicliffe, Erdman, Reimer, & Shearer, 2008).

Another supplement that is popular among combat sports athletes is a naturally-occurring

fatty acid, conjugated linoleic acid (CLA). Combat sports athletes consume CLA supplements

because of its claimed ability to reduce fat mass, improve insulin sensitivity, and decrease

plasma glucose. While most of the research on the effects of CLA have been conducted on

animals (Langan-Evans et al., 2011), there have been some studies conducted using human

subjects that show promise. A randomized, double-blind study of 60 overweight or obese

individuals found that supplementation of 3.4 – 6.8 g/d of CLA was associated with a significant

reduction in body fat, compared to a placebo group receiving 9 g/d of olive oil (Blankson et al.,

2000). This study did not find that 6.8 g/d of CLA was more effective than 3.4 g/d of CLA.

Another research, with a similar design, observed this association among 53 healthy individuals.

This double-blind trial resulted in a 3.8% reduction in body-fat percentage in the CLA group,

which was significantly different from the olive oil placebo group (Smedman & Vessby, 2001).

17
A study of CLA supplementation among subjects with experience in resistance training found

promising but no statistically significant effects on body mass and fat mass (Kreider, Ferreira,

Greenwood, Wilson, Almada, 2002). The merits of CLA supplementation among combat sports

athletes are questionable after considering the findings of Kreider et al. (2002).

The review by Langan-Evans et al. (2011) identified carnitine supplementation as a

common practice among combat sports athletes. Normally consumed as part of a regular diet,

carnitine is stored in the muscles and plays a role in the transportation of fatty acids for

oxidation. The primary issue with supplementation of L-carnitine is that it is not put to use in the

muscle, rather it passes through the body as free carnitine, unable to be utilized (Barnett et al.,

1994). Research by Stephens et al. (1985) suggested that insulin may be a factor in muscular

carnitine retention. More recent efforts have found that carnitine levels increase in the muscle

when supplementation is taken at a time where carbohydrates are readily available (Stephens,

Constantin-Teodosiu, Laithwaite, Simpson, & Greenhaff, 2006). In regards to combat sports

athletes, the literature suggests the potential benefits of L-carnitine supplementation may not be

worth the carbohydrates needed to retain the carnitine in the muscle tissue.

Multivitamins are a popular immune-boosting option for combat sports athletes

practicing RWL (Langan-Evans et al., 2011). There is a plethora of information regarding the

role of micronutrients found in multivitamins and their role in immune functions. The stress of

training has been investigated for its role in suppressing the immune system (Bishop, Blannin,

Walsh, Robson, & Gleeson, 1999). Additionally, the risk for nutritional deficiencies could

potentially exacerbate the adverse effects of training on the immune system of combat sports

athletes. Particularly during a weight cut, combat sports athletes reduce carbohydrate intake to

the point of micronutrient deficiency (Langan-Evans et al., 2011). While research has identified

18
that healthy adults practicing diets focused on macronutrient intake can consume adequate levels

of micronutrients (Gardner et al., 2010), it remains to be determined if combat sports athletes

regularly consume micronutrients at levels that would or would not warrant the use of

multivitamins.

In order to increase eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)

intake, many combat sports athletes supplement their diets with fish oils during a weight cut.

These fatty acids are claimed to reduce inflammation and boost immune function (Buckley &

Howe, 2009; Ramel, Martinez, Bandarra, & Thorsdottir, 2010). Simopoulos (2007) suggested

that many athletes should aim to consume EPA and DHA at a ratio 2:1, respectively, with

consumption of 1 to 2 g/d of the fatty acids. This is much different from the standard ratio of

today’s Western diets which contain EPA and DHA at ratios between 10:1 and 20:1, which may

limit the body’s ability to reduce inflammation during and after high-intensity activity

(Simopoulos, 2007). A recent study observed that EPA and DHA were effective in decreasing

indicators of inflammation; however, these effects were not significant after 60 minutes of

moderate exercise (Bloomer, Larson, Fisher-Wellman, Galpin, & Schilling, 2009). Bloomer et

al. (2009) found that exercise-trained men experienced minimal inflammation and oxidative

stress responses to hour-long bouts of exercise, regardless of EPA/DHA supplementation.

Another supplement that is often used by combat sports athletes is the flavonoid

quercetin. It is claimed to provide antiviral immune support, attractive to athletes looking to

avoid upper respiratory tract infections (URTIs) (Langan-Evans et al., 2011). The effectiveness

of quercetin in reducing URTI incidence has been observed in a double-blind randomized trial

involving 40 trained cyclists (Nielman et al., 2007). There is additional evidence suggesting that

quercetin supplementation may be effective in reducing the stress of exercise on the immune

19
system, reducing the risk for URTI (Davis, Murphy, McClellan, Carmichael, & Gangemi, 2008).

While the body of knowledge regarding quercetin supplementation is still growing, immune

benefits appear to be present when supplementation is 1 gram daily.

Other supplements offer potential benefits to combat sports athletes looking to make a

weight cut; however, there is a large variation in the quality and validity of current evidence

regarding each supplement. The most promising of these supplements is bovine colostrum, the

first milk from a cow. Bovine colostrum has been associated with improved biomarkers of

immune health and lower incidence of URTI (Crooks, Wall, Cross, & Rutherfurd-Markwich,

2006; Davison & Diment, 2010). There are conflicting reports regarding the benefits of

Echinacea supplementation. The herbal supplement has some scientific merit; however, more

recent studies do not corroborate with those findings (Hall, Fahlman, & Engels, 2007; Senchina,

Hallam, Dias, & Perera, 2009; Szolomicki, Samochoweic, Wojcicki, & Drozdzik, 2000).

Supplementation of the amino acid glutamine has no observed benefits or risks in human trials;

however, it is commonly consumed by combat sports athletes under the assumption that

supplementation will aid in muscle recovery (Gleeson, 2008; Langan-Evans, 2011). Manuka

honey possesses a high level of antibacterial activity, but research has yet to identify if it has any

role in reducing the incidence of URTI (Badet & Quero, 2011). Athletes are likely testing other

supplements in the search of a competitive edge, particularly during the weight cutting process.

Gaps in Knowledge

The evidence suggests that athletes in combat sports commonly practice intentional

dehydration, limit nutritional intake, and practice questionable supplement usage (Brito et al.,

2012; Fleming & Costarelli, 2007; Hoffman & Maresh, 2011; Langan-Evans et al., 2011;

Matthews & Nicholas, 2016; Pallares et al., 2016; Franchini et al., 2012; Pettersson & Berg,

20
2014; Pettersson & Berg, 2014; Reljic et al., 2015; Timpmann et al., 2008). These practices,

aimed at achieving RWL, are likely detrimental to performance in competition within physical

(Cheuvront et al., 2004; Nielsen et al., 1981) and cognitive domains (Edwards et al., 2007;

Wilson & Morley, 2003). The practice of intentional dehydration is particularly risky due to its

association with recent hospitalizations and deaths (Carroll, 2018; MMANewPL, 2017) and

deaths (Cruz, 2013; Rondina, 2017; Zidan, 2014). Further understanding of the practices of

MMA fighters is needed due to the lack of breadth of knowledge regarding their RWL practices.

Additionally, this subpopulation of combat sports athletes also possesses the most extreme

observed losses in body mass (Coswig et al., 2015; Matthews & Nicholas, 2016). These findings

suggest that MMA fighters may be placing themselves at the greatest risk for hospitalization or

death. With the risks well-known and publicized, creating changes within the culture of combat

sports may be necessary to catalyze revolutionary changes in the practices and administration of

combat sports athletes and promotions. Due to its place in the sport, a reasonable approach for

researchers is to seek opportunities to clarify which weight-management practices are most

strongly associated with health and optimal performance. Despite the popularity of weight-

cutting through intentional dehydration and dietary fasting, there is little evidence of how

hydration, nutrition, and dietary supplementation impact MMA fighters’ physical performance.

The sport of MMA combines aspects of most combat sports and may place a unique combination

of exercise-induced stresses on the sport’s athletes. Due to the gaps in our knowledge regarding

MMA athletes, the risks involved in RWL, and the implications of weight-management practices

in combat sports, further research is warranted into assessing the role of hydration, nutritional

intake, and dietary supplementation in predicting the athletic performance of MMA athletes.

21
 CHAPTER 3

METHODS

Study Design

This research is a cross-sectional study. Nutrition, hydration, body composition, and

performance were measured among a sample of MMA fighters at various stages of the week

prior to competition. The research methods included participant screening, measurements of

height, weight, bone girths, skinfold measurements, punch force, and energy expenditure.

Additionally, participants provided food journals, personal supplement usage, RWL strategies

utilized, and their perceptions of the RWL process and their performance.

Recruitment and Data Collection Procedures

All participants were amateur or professional MMA fighters recruited from competitions

within fight promotion organizations in the southeastern United States. Recruitment and

measurement protocols were approved by the University of Mississippi Institutional Review

Board. Recruitment occurred via written email invitation [Appendix A] which may have been

followed by additional methods of recruitment such as phone calls and emails to accompany the

written invitation. Participants were provided informed consent and contact information of the

primary investigator prior to participation in the study [Appendix B]. Information gathered

through this study such as participants’ identities was coded at the conclusion of data collection

to provide confidentially. Screening was conducted to ensure participants are 18 years or older.

Individuals who did not meet the screening criteria were thanked for their time and invited to

22
participate once they are eligible, if possible. Participants were invited to perform multiple cycles

of RWL, if possible. Data collection required a baseline measurement 7-10 days prior to weigh-

ins, before the RWL cycle. Endpoint data were collected approximately 24 hours after weigh-ins.

Through recruitment and retention efforts, nine male MMA fighters completed

participation and provided their complete, reliable data. Recruitment was affected by several

factors including injuries, fight cancellations, failure to submit completed materials at the fault of

the participant, rejection of participation, and event cancellation in response to the COVID-19

pandemic. Without any direct incentives, multiple points of contact were skeptical of the benefit

they and/or their fighters would receive through participation.

Variables and Measurement

Nutrition

Nutritional data were assessed through the collection of self-reported 7-day food journals.

The food journals provided information regarding caloric intake (kcal), carbohydrate intake (g),

protein intake (g), fat intake (g), and water intake (fl oz). Diet records were analyzed using the

Nutritional Data System for Research (NDSR) (Schakel, 2001; Schakel, Buzzard, & Gebhardt,

1997; Schakel, Sievert, & Buzzard, 1988) which utilizes a validated database suitable for

nutrition analysis in research. Dietary intake estimations were corrected for BW. Participants

provided lists of dietary supplements used during the study. Prior to analysis, dichotomous

variables were created for each supplement reported by participants with responses being coded

as “0” for no supplement usage or “1” for supplement usage, respective to each supplement

observed across the sample.

A 7-day physical activity log was provided alongside food journals. This information was

used to determine physical exertion and caloric needs of training during fight-week. Dietary and

23
activity information was necessary to determine total energy availability (TEA) which was

crucial in determining the acute effectiveness of the participants’ training diet in meeting fueling

needs. Total energy expenditure (TEE) was calculated as the sum of basal metabolic rate (BMR),

exercise energy expenditure (EEE), and thermic effect of food (TEF). The Cunningham

equation, as seen in (1), was used to assess BMR due to its accuracy and the availability of

information regarding lean body mass (Thompson & Manore, 1996; Fink, Burgoon, & Milesky,

2006). The TEF of participants was calculated using the generalized approach of estimating TEF

as 10% of caloric intake (Reed & Hill, 1996). Additionally, EEE was assessed using metabolic

equivalent (MET) estimations for caloric expenditure during activity, as seen in (2). Mynarski,

Krolikowka, Rozpara, Nawrocka, & Puciato (2013) estimated MET values for various martial

arts-related activities including aikido, capoeira, jujutsu, karate, kickboxing, and MMA. For each

activity, EEE was calculated and added to reflect a daily total for EEE which was used to

accurately estimate TEE.

Total energy availability was defined during three distinct timeframes: Pre-RWL, RWL,

and Refeeding. The length of each timeframe varied between subjects. The “RWL” dietary

timeframe was defined as the time between the last full meal during the Pre-RWL timeframe and

the time of weigh-ins. From the “RWL” timeframe, the dichotomous variable Short Fast was

created and scored as a “1” for fasting periods of less than 24 hours and scored as “0” otherwise.

Therefore, “Pre-RWL” referred to the timeframe of measured dietary intake prior to dietary

restriction, and “Refeeding” referred to the timeframe of measured dietary intake after weigh-ins

and up to the time of competition. From TEA, calculated as the difference in caloric intake and

TEE (the sum of BMR, EEE, and TEF) during three distinct timeframes, the dichotomous

variable Acute Low Energy Availability (ALEA) was created. For positive values of TEA, ALEA

24
was coded as “0”, and for negative values of TEA, ALEA was coded as “1”. ALEA, being only

an acute assessment of energy availability, is not a valid assessment of risk for RED-S among

this population. Therefore, conclusions of the prevalence and/or the relative risk for RED-S were

not drawn during this study. Comparisons were conducted analyzing the difference in the

consumption of carbohydrates, protein, and fat, each represented as grams per kilogram of body

mass.

BMR=500+22×FFM(kg) (1)

EEE/min=0.0175×MET×BW(kg) (2)

Hydration Status

Hydration status was determined using urine specific gravity. There are several methods

for measuring urine specific gravity. Refractometry has been shown to be more consistent and

reliable than alternative methods of measuring urine specific gravity (Minton, O’Neal, & Torres-

McGehee, 2015; Stuempfle & Drury, 2003). Minton et al. (2015) showed that either manual or

digital refractometry is appropriate for measuring urine specific gravity; hence, this study

utilized a digital refractometer to obtain accurate data in a timely manner. Hydration status was

defined as euhydration or dehydration. The dichotomous variable Dehydration was scored as “1”

if the subject’s USG is greater than 1.020 and scored as “0” otherwise. This definition of

dehydration using urine specific gravity was made in accordance with NCAA standards for

determining hydration status among collegiate wrestlers (National Collegiate Athletic

Association, 2017). Additional information regarding intentional dehydration strategies such as

25
sauna-suit use, diuretics use, and sauna use were collected with dietary data in the 7-day food

journals. These data were used to score the dichotomous variable Intentional Dehydration

Strategies as “1” if the participant indicated using any intentional dehydration strategy and “0”

otherwise.

Kinanthropometrics

The participants’ height and weight were assessed at baseline. Bone girths and skinfold

measurements were taken prior to RWL cycle. Skinfold measurements were taken again on the

day of competition. All girth and skinfold measurements were taken by a Level-1 certified

International Society for the Advancement of Kinanthropometry (ISAK) anthropometrist

following ISAK protocol [Appendix C]. ISAK methods were utilized to provide essential

consistency and validity to the measurement of skinfolds (Hume & Marfell-Jones, 2008). In

addition to skinfold measurements, ISAK body composition analysis provided information on

height, weight, as well as muscle and bone mass (MBM). Body fat (BF) was estimated using

Civar’s equation, as seen in (3) (Civar, Ozer, Aktop, Tercan, & Ayceman, 2003), due to its

validated consistency with dual-energy x-ray absorptiometry analyses of athletic populations

(Lopez-Taylor et al., 2018). By comparing baseline and endpoint values for BW, BF%, and

MBM%, new variables were calculated to reflect the changes in these values as a percentage.

The body composition variables that will be relevant to statistical tests are ∆BW, ∆BF, and

∆MBM. Additionally, dichotomous variables BF Increase and MBM Increase were scored as “1”

to reflect increases in body fat percentage and/or muscle and bone mass percentage, respectively,

and scored as “0” otherwise.

BF%=(0.432×triceps)+(0.193×abdomen)+(0.364×biceps)+(0.077×BW)-0.891 (3)

26
Performance

This study analyzed performance in terms of punching velocity. Punching velocity was

measured using Everlast’s PIQ Blue System, a wearable technology that utilizes two 3-axis

accelerometers and a 3-axis gyroscope to assess the movement and performance of fighters

during training. Data collected by the PIQ sensors was transmitted to an accompanying mobile

app in real-time. PIQ sensors were worn by fighters, on their gloves, during training sessions.

Punching velocity was assessed at baseline and endpoint. These figures were used to calculate

the absolute change in peak velocity associated with RWL and refeeding. This data was reflected

in the variable ∆Velocity. The dichotomous variable Improved Punching Velocity was scored as

“1” for positive values of ∆Velocity and scored as “0” otherwise. Competition results were also

analyzed as a measure of performance, being coded as “1” for a win and “0” otherwise.

Responses to the question, “How would you rate your performance in the fight?” were used to

score the variable Self-Rated Performance. This variable was utilized in analyses as a categorical

dependent variable reflecting self-rated performance on a 5-point scale (1 = Very Poor to 5 =

Very Good).

Demographics and Other Variables

Participants were asked to provide demographic and other general information. This data

included: age; race/ethnicity; sex; level of competition; and primary fighting style.

Data Analysis

The IBM SPSS statistical software was used for all statistical analyses. All statistical tests

utilized a two-tailed 95% confidence interval or a significance level of α=.05.

27
 To answer the first research question, descriptive statistics such as frequencies, means,

and standard deviations were calculated for the relevant variables and measurements TEA,

ALEA, short fast, dehydration, intentional dehydration strategies, supplementation, and body

composition. Baseline, weigh-in, and endpoint values were calculated for each measure, while

body composition was only evaluated at baseline and endpoint.

To answer the second research question and determine the associations between

hydration, acute energy availability, and dietary supplementation with changes in body mass and

composition among MMA fighters, ANOVAs were conducted using the independent variables

TEA, ALEA, short fast, dehydration, intentional dehydration strategies, and supplementation

with the dependent variables ∆BW, ∆BF, BF increase, ∆MBM, MBM increase.

Pearson’s correlation coefficients were calculated between all factors included in this

study. To answer the third research question and determine the relationships between key

variables, special attention was paid to Pearson’s correlation results regarding the key variables

TEA, ALEA, short fast, dehydration, intentional dehydration strategies, supplementation. ∆BW,

∆BF, ∆MBM, BF increase, MBM increase, ∆Velocity, and improved punching velocity.

To answer the fourth research question, t-tests were conducted to observe if differences in

the dependent variables Improved Punching Velocity and Self-Rated Performance were observed

across various conditions associated with the nominal independent variables ALEA, short fast,

dehydration, intentional dehydration strategies, supplementation, BF increase, and MBM

increase. ANOVA was used to determine the associations between the independent variables and

the dependent variable ∆Velocity.

28
 Table 1 summarizes definitions and measurements of the variables used in analyses.

Table 2 outlines relevant information for analyses such as research questions, alternative

hypotheses, and plans for analyses.

Table 1
Variable Definitions and Measurements
Variables Definition Coding
The respondent has a USG ≥ 1.020 and
is dehydrated, in accordance with NCAA 0 = Hydrated, USG < 1.020
Dehydration
regulations on weight-management 1 = Dehydrated, USG ≥ 1.020
among collegiate wrestlers.
Defined by a negative value for TEA,
0 = Adequate Energy, TEA ≥ 0
ALEA which is the difference between caloric
1 = ALEA, TEA < 0
intake and TEE.
Variables will be created for each 0 = No Supplementation
Supplementation
supplement observed. 1 = [Supplement] Use
Short Fast Defined by a fasting period of less than 0 = 24+ Hour Fasting Period
Period 24 hours. 1 = Fasting Period < 24 Hours
Percentage change in body mass for
∆BW participants between baseline and Percentage change in BW.
endpoint.
Percentage change in body fat for
∆BF participants between baseline and Percentage change in BF%.
endpoint.
Percentage change in muscle and bone
∆MBM mass for participants between baseline Percentage change in MBM%.
and endpoint.
Absolute change in peak punch velocity
∆Velocity for participants between baseline and Change in punching velocity.
endpoint.
Single self-rated score to the question,
Self-Rated “How would you rate your performance Numerical value of ranging 1-5,
Performance in the fight?” Responses range from very with 5 being the highest rating.
poor to very good.
Dichotomous coding for the result of
0 = Loss, Draw, or No-Contest
Fight Result MMA competition. Losses, draws, and
1 = Win
no-contests will be coded the same.

29
Table 2
Hypotheses and Statistical Analysis
Research Question Hypothesis Analysis
What is the status of MMA fighters
Frequencies for dehydration,
pertaining to dehydration, acute energy
ALEA, and supplement use
availability, dietary supplementation, N/A
and body composition at different
M and SD for BW, BF, MBMa
stages of combat preparation?
Dehydration has a negative effect on changes in ANOVAs
What effects do hydration, acute
weight and body composition during RWL.
energy availability, dietary
Energy availability has a positive effect on changes in IVs: dehydration, ALEA, and
supplementation have on changes to
weight and body composition during RWL. supplementation
weight and body composition during
Dietary supplementation has an effect on changes in
RWL?
weight and body composition during RWL. DVs: ∆BW, ∆BF, and ∆MBM
Changes in BW, BF%, and FFM% are positively
Are changes in performance after Pearson correlation coefficients
correlated with changes in performance.

30
refeeding correlated with acute body
composition changes and hydration Factors: dehydration, ∆BW, ∆BF,
Dehydration is negatively correlated with changes in
status? ∆MBM, and ∆Velocity
performance.
Independent-samples t-tests for
Dehydration is negatively associated with Improved Punching Velocity and
How are hydration, acute energy performance. Self-Rated Performance
availability, dietary supplementation, Energy availability is positively associated with
and changes in weight and body performance. ANOVA with DV: ∆Velocity
composition associated with objective Dietary supplementation is associated with
and perceived performance among performance. IVs: ALEA, fasting, dehydration,
MMA fighters? Changes in BW, BF%, and FFM% are positively intentional dehydration strategies,
associated with performance. supplementation, ∆BW, ∆BF, and
∆MBM

Note. Italicized text used for dependent variables in Analysis column.

a
BW, BF, & MBM will be presented as baseline and endpoint values. Other variables will have an additional weigh-in value.
 CHAPTER 4

RESULTS

Sample Characteristics

The sample for analysis consisted of nine male participants who provided

complete participation through a non-simulated trial of RWL and refeeding

during a week of competition. Among the sample, six participants (66.7%) were

professional athletes, and three (33.3%) were amateur athletes. Participant age

ranged between 24 and 35 years (M=29.44, SD=3.71).

Key Parameters during Rapid Weight Loss and Refeeding

Table 3 presents information regarding the nutritional, hydration,

anthropometric, and performance parameters assessed at the three stages of rapid

weight loss that were observed in this study. Fasting periods between 19 and 72

hours were observed (M=34.80 h, SD=19.92). The sample displayed energy

deficits during the Pre-RWL, RWL, and fight-week timelines (M=-4692.52,

SD=5540.86). Additionally, a mean USG (M=1.024, SD=0.006) above the

threshold for the diagnosis of dehydration was observed at weigh-ins.

31
 Table 3
Sample Characteristics at Various Stages of Rapid Weight Loss (N=9)
Mean (SD)
Pre-RWL RWL Refeeding
Duration of Stage (days) 5.22 (0.79) 1.45 (0.83) 1.13 (0.8)

Total Energy Availability -3678.59 -2473.70 1459.76

(4786.80) (1235.28) (1080.58)

Carb (g)/kg 1.12 (1.03) 0 (0) 5.35 (2.41)

Protein (g)/kg 1.29 (0.66) 0 (0) 1.74 (0.59)

Fat (g)/kg 0.65 (0.37) 0 (0) 1.12 (0.60)

Urine Specific Gravity 1.006 (0.004) 1.024 (0.006) 1.008 (0.008)

Body Mass (lb) 178.81 (20.19) 164.27 (18.49) 175.43 (18.58)

Body Fat % 11.09 (1.85) -- 10.71 (1.81)

Muscle & Bone Mass % 52.81 (2.31) -- 53.21 (2.97)

Peak Punch Velocity (mph) 18.44 (5.99) -- 17.12 (5.29)

Table 4 presents information detailing the frequency of observations of

key nutritional, hydration, anthropometric, and performance factors across the

three stages of rapid weight loss that were observed in this study. Low energy

availability and dehydration were prevalent at various stages of the RWL-

32
refeeding cycle. Nearly every participant (n=8, 88.9%) had a negative value for

total energy availability within the timeframe of the entire fight week. Despite the

prevalence of dehydration among participants at weigh-ins (n=8, 88.9%), all but

one participant was able to achieve euhydration prior to competition. Caffeine

(n=4, 44.4%) and cannabidiol (CBD) oil (n=3, 33.3%) supplementation was

observed. One participant utilized both green tea and apple cider vinegar in

pursuit of weight and performance goals. Intentional dehydration practices were

commonly utilized among the sample (n=5, 55.6%). These practices included

sauna (n=1, 11.1%) and sauna suits (n=3, 33.3%), as well as one participant

(11.1%) reportedly achieving significant perspiration through utilizing the heater

of his vehicle during the 2-hour commute to the weigh-in location. Almost half of

the participants (n=4, 44.4%) utilized a shorter fasting period of less than 24

hours. Most participants (n=7, 77.8%) successfully met their goal weight to fully

qualify for competition.

33
Table 4
Frequencies for Rapid Weight Loss Parameter among MMA athletes (N=9)
Frequency Percentage
Acute Low Energy Availability
Pre-RWL 8 88.9%
RWL 9 100%
Refeeding 1 11.1%
Fight Week 8 88.9%

Short Fast Period (<24 hours) 4 44.4%

Dehydration
Baseline 0 0%
Weigh-in 8 88.9%
Endpoint 1 11.1%

Intentional Dehydration Strategy a 5 55.6%

Met Weight Goal 7 77.8%

Won Fight 2 22.2%

Improved Punching Velocity b 5 55.6%

Self-Rated Performance
Very Poor 0 0%
Poor 2 22.2%
Average 2 22.2%
Good 3 33.3%
Very Good 2 22.2%
a
Participants indicated various strategies including sauna and sauna suits,
among others.
b
Indicated by an endpoint peak punching velocity value that was greater than
the baseline punching velocity measured.

34
Effects of Hydration, Nutrition, and Supplementation during RWL

ANOVAs were used in identifying the effects that variables related to

nutrition, hydration, and supplementation have on acute changes to body weight,

body composition, and punching velocity. These analyses, with the dependent

variables ∆BW, ∆BF, and ∆MBM, addressed the second research question. Table

5 presents the results from these analyses, in addition to results from ANOVAs

calculated with the dependent variable ∆Velocity. No statistically significant

effect was observed. Several F-values reflected differences greater than 1% for

the dependent variables ∆BW, ∆BF, and ∆MBM. There was no statistically

significant effect of ALEA during refeeding on ∆BW, F(1,7)=4.805, p=0.064.

ALEA during refeeding had no statistically significant effect on ∆MBM,

F(1,7)=1.024, p=0.345. The effect of fasting duration (short vs long) on ∆BW

was not statistically significant, F(1,7)=1.896, p=0.211. Dehydration at weigh-ins

had an effect on ∆BF that was not statistically significant, F(1,7)=4.554, p=0.070.

Intentional dehydration behaviors had no statistically significant effect on ∆BW,

F(1,7)=1.055, p=0.338, and ∆BF, F(1,7)=2.391, p=0.166. Caffeine

supplementation had no significant effect on ∆BF, F(1,7)=3.083, p=0.123, or

∆MBM, F(1,7) = 1.328, p = 0.287. While many of the independent variables

35
expressed near-zero effects on ∆Velocity, F-values greater than one were

observed for the independent variables Short Fast, F(1,7)=1.503, p=0.260, and

Caffeine Supplementation, F(1,7)=1.655, p=0.239.

36
Table 5
One-Way ANOVA for Changes in Body Composition during RWL (N=9)
df a F p-value
∆BW x Pre-RWL ALEA 1,7 0.218 0.655
∆BF x Pre-RWL ALEA 1,7 0.013 0.914
∆MBM x Pre-RWL ALEA 1,7 0.318 0.591
∆Velocity xPre-RWL ALEA 1,7 0.043 0.842
∆BW x Refeeding ALEA 1,7 4.805 0.064
∆BF x Refeeding ALEA 1,7 0.219 0.654
∆MBM x Refeeding ALEA 1,7 1.024 0.345
∆Velocity x Refeeding ALEA 1,7 0.000 0.987
∆BW x Short Fast 1,7 1.896 0.211
∆BF x Short Fast 1,7 0.043 0.841
∆MBM x Short Fast 1,7 0.900 0.374
∆Velocity x Short Fast 1,7 1.503 0.260
∆BW x Weigh-in Dehydration 1,7 0.541 0.486
∆BF x Weigh-in Dehydration 1,7 4.554 0.070
∆MBM x Weigh-in Dehydration 1,7 0.598 0.464
∆Velocity x Weigh-in Dehydration 1,7 0.003 0.961
∆BW x Endpoint Dehydration 1,7 0.398 0.548
∆BF x Endpoint Dehydration 1,7 0.082 0.782
∆MBM x Endpoint Dehydration 1,7 0.032 0.864
∆Velocity x Endpoint Dehydration 1,7 0.000 0.987
∆BW x Intentional Dehydration Strategies 1,7 1.055 0.338
∆BF x Intentional Dehydration Strategies 1,7 2.391 0.166
∆MBM x Intentional Dehydration Strategies 1,7 0.381 0.556
∆Velocity x Intentional Dehydration Strategies 1,7 0.632 0.453
∆BW x Caffeine 1,7 0.323 0.588
∆BF x Caffeine 1,7 3.083 0.123
∆MBM x Caffeine 1,7 1.328 0.287
∆Velocity x Caffeine 1,7 1.655 0.239

Note: Some variables excluded due to violations to the assumption of

homogeneity of variance.
a
Degrees of freedom represented as “between-groups,within-groups”

37
Pearson Correlation Coefficients: Nutrition, Hydration, Body Composition,

and Performance Parameters

To answer the third research question, Pearson’s correlation coefficients

were estimated for the parameters related to changes in body composition,

hydration, and changes in peak punching velocity. Table 6 presents these results

for key parameters as well as additional Pearson’s correlation coefficients for

other factors included in the study. With no statistically significant effect sizes

observed in ANOVA analyses, this approach was taken to provide a more-

comprehensive analysis of the observations made among this sample of MMA

fighters. The dependent variables in the scope of these Pearson’s correlation

analyses were ∆Velocity, Improved Punching Velocity, Self-Rated Performance,

and Fight Result.

Acute low energy availability, for each stage of the study, did not express

statistically significant Pearson’s correlation coefficients for any of the dependent

variables. Total energy availability during the RWL stage of the study had a

statistically significant positive correlation coefficient with ∆Velocity (r=0.688,

p<.05). The duration of fasting, in hours, had a statistically significant negative

correlation with ∆Velocity (r=-0.763, p<.05) and improved punching velocity

38
(r=-0.680, p<.05). Fasting periods of less than 24 hours were positively correlated

with improved punching velocity (r=0.800, p<.01). Improved punching velocity

was positively correlated with protein consumption during the Refeeding stage

(r=0.669, p<.05). Endpoint USG was negatively correlated with self-rated

performance (r=-0.678, p<.05). Dehydration status and intentional dehydration

strategies had no statistically significant correlations with the performance

parameters in this study. ∆MBM had a statistically significant positive correlation

with ∆Velocity (r=0.698, p<.05). Increased body fat percentage had a significant

negative correlation with ∆Velocity (r=-0.951, p<.001). Fight result was

negatively correlated with fat consumption during the refeeding timeframe (r=-

0.689, p<.05).

Age was negatively correlated with weigh-in USG (r=-0.691, p<.05) and

positively correlated with endpoint USG (r=0.677, p<.05). Changes in body fat

percentage, from baseline to endpoint, were negatively correlated with changes in

muscle-and-bone mass across the same time-frame (r=-0.709, p<.05). There was

a significant positive correlation between self-rated performance and improved

punching velocity (r=0.676, p<.05).

39
Table 6
Pearson’s r: Nutrition, Hydration, Body Composition, Supplementation, & Performance (N=9)
Pearson’s r
Improved Self-Rated
∆Velocity Fight Result
Velocity Performance
Acute Low Energy Availability a
Pre-RWL -0.078 -0.316 0.184 0.189
Refeeding 0.006 -0.395 0.147 0.661
Total Energy Availability
Pre-RWL -0.074 0.174 -0.286 -0.469
RWL 0.688* 0.652 0.361 -0.292
Refeeding 0.165 0.414 -0.303 -0.487
Fasting
Duration in hours -0.763* -0.680* -0.378 0.263

40
Fasting < 24 hours 0.420 0.800** 0.583 0.060
Carbohydrates g/kg of Body Mass
Pre-RWL 0.393 0.456 0.107 0.097
Refeeding 0.262 0.543 0.010 -0.070
Fat g/kg of Body Mass
Pre-RWL 0.503 0.636 0.203 -0.378
Refeeding 0.202 0.160 -0.452 -0.689*
Protein g/kg of Body Mass
Pre-RWL 0.251 0.446 -0.150 -0.161
Refeeding 0.467 0.669* 0.199 -0.605
Supplement Use
Caffeine -0.437 -0.100 -0.676* -0.478
CBD Oil -0.595 -0.316 -0.590 -0.378
Urine Specific Gravity
Baseline -0.069 -0.034 0.159 0.180
Weigh-in -0.196 0.243 0.230 0.130
Endpoint 0.032 -0.352 -0.678* -0.409
Dehydration a
Weigh-in 0.019 0.395 0.184 0.189
Endpoint 0.006 -0.395 -0.516 -0.409
Intentional Dehydration Strategies -0.288 0.100 -0.163 -0.060
Body Composition
∆BW -0.235 0.463 0.193 -0.454
∆BF -0.623 -0.047 -0.380 -0.023
∆MBM 0.698* 0.144 0.455 0.546
BW Increase -0.434 0.158 0.074 -0.378

41
BF Increase -0.951*** -0.395 -0.516 -0.189
MBM Increase 0.497 0.060 0.279 0.289
BW% Reduced Making Weight 0.178 -0.029 0.030 0.438
a
Pearson’s r-values could not be computed due to constant values in at least one variable.
*Significant at the 0.05 level (2-tailed)
**Significant at the 0.01 level (2-tailed)
***Significant at the 0.001 level (2-tailed)
Independent-Samples T-Tests of Performance

Independent-samples t-tests were conducted to compare performance

outcome parameters to conditions related to acute energy availability, fasting,

hydration status, intentional dehydration strategies, supplementation, and acute

changes in body composition.

Table 7 presents findings from independent-samples t-tests with the

independent variables reflecting the conditions ALEA, short fast, dehydration,

supplementation, BF increase, and MBM increase. The dependent variable in

these analyses was the dichotomous variable improved punching velocity. There

was a significant difference in improvements to punching velocity for short

fasting (M=1.000, SD=0.000) and long fasting (M=0.200, SD=0.447) conditions

t(7)=-3.528, p=0.010. There were no other statistically significant findings to

report from these analyses.

42
Table 7
Independent-Samples T-tests for Improved Punching Velocity (N=9)
M SD df t-statistic p-value
Pre-RWL ALEA 7 0.882 0.407
No 1.000 0.000
Yes 0.500 0.535
Post-RWL ALEA 7 1.139 0.292
No 0.625 0.518
Yes 0.000 0.000
Short Fast 7 -3.528 0.010*
Long Fast 0.200 0.447
Short Fast 1.000 0.000
Caffeine Use 7 0.266 0.798
No 0.600 0.548
Yes 0.500 0.577
CBD Oil Use 7 0.882 0.407
No 0.667 0.516
Yes 0.333 0.577
Weigh-in Hydration 7 -1.139 0.292
Dehydration 0.625 0.518
Euhydration 0.000 0.000
Endpoint Hydration 7 1.139 0.292
Dehydration 0.000 0.000
Euhydration 0.625 0.518
Dehydration Strategies 7 -0.266 0.798
Did not use 0.500 0.577
Used 0.600 0.548
BF Increase 7 1.139 0.292
No 0.625 0.518
Yes 0.000 0.000
MBM Increase 7 -0.158 0.879
No 0.500 0.707
Yes 0.571 0.535

Note: Some IVs were not included because of constant values.

*Significant at the 0.05 level (2-tailed)

43
 Table 8 presents findings from the independent-samples t-tests with the

dependent variable self-rated performance There was a significant difference in

self-rated performance for caffeine abstention (M=4.200, SD=0.837) and caffeine

supplementation (M=2.750, SD=0.957) conditions t(7)=2.428, p=0.046. There

were no other statistically significant findings to report from these analyses.

44
Table 8
Independent-Samples T-tests for Self-Rated Performance (N=9)
M SD df t-statistic p-value
Pre-RWL ALEA 7 -0.496 0.635
No 3.000 0.000
Yes 3.630 1.188
Post-RWL ALEA 7 -0.394 0.705
No 3.500 1.195
Yes 4.000 0.000
Fasting 7 -1.898 0.100
24+ hours 3.000 1.000
< 24 hours 4.250 0.957
Caffeine Use 7 2.428 0.046*
No 4.200 0.837
Yes 2.750 0.957
CBD Oil Use 7 1.932 0.095
No 4.000 1.095
Yes 2.670 0.577
Weigh-in Hydration 7 -0.496 0.635
Dehydration 3.630 1.188
Euhydration 3.000 0.000
Endpoint Hydration 7 1.594 0.155
Dehydration 2.000 0.000
Euhydration 3.750 1.035
Dehydration Strategies 7 0.438 0.675
Did not use 3.750 0.500
Used 3.400 1.517
BF Increase 7 1.594 0.155
No 3.750 1.035
Yes 2.000 0.000
MBM Increase 7 -0.768 0.468
No 3.000 1.414
Yes 3.71 1.113

Note: Some IVs were not included because of constant values.

*Significant at the 0.05 level (2-tailed)

45
 CHAPTER 5

DISCUSSION

Discussion of Findings

The present study utilized a multi-faceted approach to explore how

hydration, nutrition, dietary supplementation, and body composition are

associated with athletic performance among MMA athletes practicing rapid

weight loss. The data and analyses provided insights into the nutritional

strategies, hydration status, acute body composition changes, punching velocity

changes, and self-perceived quality of performance of MMA fighters practicing a

non-simulated period of rapid weight loss and refeeding during a week of

competition. The participants in this study were generally successful at achieving

their desired weight loss through RWL (n=7, 77.8%).

The observed nutritional, hydration, and supplementation strategies

associated with RWL among this sample were consistent with previous findings

among various subgroups of combat sports athletes (Brito et al., 2012; Fleming &

46
Costarelli, 2007; Hoffman & Maresh, 2011; Langan-Evans et al., 2011; Matthews

& Nicholas, 2016; Pallares et al., 2016; Franchini et al., 2012; Pettersson & Berg,

2014; Pettersson & Berg, 2014; Reljic et al., 2015; Timpmann et al., 2008).

Although intentional dehydration had been associated with hospitalizations

(Carroll, 2018; MMANewPL, 2017) and deaths (Cruz, 2013; Rondina, 2017;

Zidan, 2014), the athletes in this study universally dehydrated intentionally, to

some extent. The prevalence of dehydration at weigh-ins was 88.9%. However,

most (n=8) participants were able to achieve euhydration prior to competition.

Potentially compounding the risks associated with dehydration, all but one

participant (n=8, 88.9%) failed to meet their dietary energy needs for the week of

competition. This was primarily correlated with caloric deficiency during the Pre-

RWL timeframe (r=0.938, p<.001), suggesting that the nutritional practices of

MMA athletes prior to fasting present the most significant risk for acute low

energy availability during the week of competition. Nutritional fasting was

practiced by all participants.

This study utilized a novel approach, relating the RWL-refeeding practice

to a quantitative marker of performance, punching velocity, specifically looking

for the determinants of performance improvement prior to competition. However,

47
acute low energy availability, for each stage of the study, did not express

statistically significant Pearson’s correlation coefficients or t-statistics for any of

the dependent variables. Total energy availability during the RWL stage of the

study had a statistically significant positive correlation coefficient with ∆Velocity

(r=0.688, p<.05). There was a significant difference in improvements to punching

velocity for short fasting (M=1.000, SD=0.000) and long fasting (M=0.200,

SD=0.447) conditions t(7)=-3.528, p=0.010. Additionally, a statistically

significant positive Pearson’s correlation coefficient was observed between short

fasting periods and improved punching velocity (r=.800, p<.01). Among the

sample, only one participant experienced improved punching velocity after an

extended fast of 26 hours.

One of the main components of the RWL-refeeding process is rehydration

during the time between weigh-ins and competition. Most participants in the

sample (n=8, 88.9%) were successful in achieving euhydration during this

timeframe. However, there was a significant correlation between endpoint urine

specific gravity and self-rated performance, suggesting that subclinical

dehydration may affect performance in discrete ways beyond the scope of this

study. Interestingly, the age of fighters was negatively correlated with weigh-in

48
USG (r=-0.691, p<.05) and positively correlated with endpoint USG (r=0.677,

p<.05). This suggests that athletes’ ability to dehydrate and rehydrate may be

influenced by age, resulting in increased difficulty to achieve optimal hydration

among older athletes. These findings suggest that fighters of advanced age and

coaches working with older fighters may benefit from pursuing competition in

weight-classes that are closer to the baseline weight of fighters, relying less on

intentional dehydration to meet RWL goals. This observation contradicts

observed behaviors among mixed martial arts athletes who attempt to lose more

weight with each performance (Park, 2019).

Changes in muscle-and-bone mass during the RWL-refeeding cycle were

positively correlated with absolute changes in punching velocity (r=0.698,

p<.05). This is a novel observation among combat sports athletes. The observed

changes in muscle-and-bone mass were negatively correlated with changes in

body fat percentage (r=-0.709, p<.05), suggesting that substrate-level metabolic

changes during RWL may significantly impact body composition, resulting in a

preference for protein catabolism over lipolysis to fuel gluconeogenesis. Due to

an observed correlation between changes in muscle-and-bone mass and changes

49
in punching velocity, prioritizing the preservation of lean mass during RWL

should be a priority for fighters and coaches in combat sports.

Relationships between fasting, body composition, and punching velocity

were observed in this study. There was a positive correlation between changes in

muscle-and-bone lean mass and changes in punching velocity. In addition to this,

the current study is the first known research to observe a relationship between

fasting periods and changes in punching velocity among combat sports athletes.

Specifically, fasting periods of less than 24 hours correlated with improved

punching velocity after rapid weight loss and refeeding. This represents a

significant finding for athletes and coaches participating in combat sports. More

research is required, however, to identify the specific mechanisms involved in

performance improvements achieved through RWL. Training load, recovery,

technical skill-level, and fasting-adaptation were not parameters included in this

study, but they may play a significant role in changes during the RWL-refeeding

cycle.

Technical skills and physiological abilities and adaptations may not be the

only predictive parameters for success in mixed-martial arts. Participants

provided a self-rated evaluation of the quality of their performance. Only caffeine

50
consumption had a statistically significant Pearson’s correlation coefficient with

self-rated performance (r=-0.676, p<.05). This is a novel observation relating

consumption of caffeine, popular among combat sports athletes (Langan-Evans et

al., 2011; Santos et al., 2014), to self-ratings of performance in MMA

competitions. The negative direction of this correlation may coincide with

caffeine-withdrawal symptoms such as anxiety, dependency and withdrawal that

have been observed by other studies (Burke, 2008; Jenkinson & Harbert, 2008;

Tunnicliffe et al., 2008). Self-rated performance was positively correlated with

improved punching velocity (r=0.676, p<.05). However, self-rated performance

did not have a statistically significant correlation with fight result, suggesting that

the athletes in the sample utilized a complex self-evaluation process that was

beyond the scope of this study. Connecting objective physical outcomes to a

subjective self-evaluation is difficult to explain given the scope of the present

study. Previous research regarding the psychology of the sport may help build a

bridge into understanding this finding. Slimani, Miarka, Briki, & Cheour (2015)

observed a strong association between mental toughness and performance in

power tests among elite kickboxers. A component of mental toughness is

confidence, a focus of psychological research in the area of MMA research

51
(Harpold, 2008; Milton, 2004; Slimani et al., 2015). Jensen, Roman, Shaft, &

Wrisberg (2013) identified major themes related to the experience of competing

in a mixed martial arts competition. Their research found a sense of community,

an emphasis on fighting skills, and a purposeful commitment to the competition

despite anxieties and fear of failure. Additionally, participants in this study

ubiquitously described a “cage reality” that revealed the mental ups and downs of

being in a mixed martial arts competition. One component of the cage reality

discussed by each participant was the physical aspects of not only the fight, but of

the demanding RWL-refeeding process. With observed correlations between

power output and mental toughness in this population (Slimani et al., 2015), the

psychological theme “cage reality” (Jensen et al., 2013) may explain how the

sample of MMA fighters in the present study self-rated their performance in

conjunction with their punching velocity following a RWL-refeeding cycle,

regardless of the result of the competition. An expanded study investigating this

physio-psychological complex among a large sample of MMA fighters would

provide an opportunity for a more-robust understanding of the determinants of

athletic performance and success among this population.

52
 One participant, Subject 9, required hospitalization following competition.

Subject 9 suffered a defeat during competition due to a fracture of the right femur

and the subsequent ruling of a technical knockout in favor of his opponent. A 27-

year old male, professional MMA fighter, Subject 9 reduced his body mass by a

relatively mild amount (13.5 lb, 6.79%). Subject 9 successfully achieved

euhydration prior to competition. However, he experienced negative changes in

body composition with an increase in body fat percentage (+0.67%) and a

decrease in muscle-and-bone mass (-2.26%). These figures represented the most

extreme observations among the sample of MMA fighters who participated in the

study. These negative body composition outcomes were concurrent with a

reduction in peak punching velocity (-19.9 mph) following a 72-hour fasting

period and refeeding. These were consequences of the RWL-refeeding cycle,

despite failing to meet the proposed 10% weight-loss criteria for LEA (De Souza

et al., 2014).

Subject 2, a 24-year old male, amateur MMA fighter directly contradicted

the experiences of Subject 9. Subject 2 was the only other participant who fasted

for 60+ hours, with a total of 67 fasted hours. This participant reduced his body

mass 22.90 lb (11.87%), resulting in relatively modest changes to body-fat

53
percentage (-0.63%) and bone-and-muscle lean mass (+1.58%). Subject 2

experienced reduced peak punching velocity (-1.2 mph) after successfully

achieving euhydration prior to competition, winning his fight by knocking out his

opponent in the first round of his fight. The observations of Subjects 2 and 9 in

this study highlight challenges for future research. Despite a comparatively, very-

long fasting period, Subject 2 experienced an increase in muscle-and-bone mass,

contradicting previous observations among adult males (Fryburg et al., 1990; Nair

et al., 1987; Pozefsky et al., 1976). With consideration of Subject 9, the findings

of this study suggest our understanding of low energy availability and

performance predictors is undeveloped. Low energy availability and relative

energy deficiency in sport are deserving of extensive attention from future

research.

Interestingly, this study observed a statistically significant positive

correlation between fighter age and endpoint USG, suggesting that older fighters

may experience some difficulty rehydrating after intentional dehydration for

RWL. A negative correlation between changes in body fat percentage and

muscle-and-bone mass percentage was indicative of substrate-level metabolic

54
changes related to the scarcity of fuel involved in RWL, with some fighters

experiencing a loss of muscle mass as a result.

After weigh-ins and refeeding, the researchers assessed peak punching

velocity to obtain a comparative measure. Other performance parameters included

fight result and self-rated performance. Of the predictor variables, only endpoint

USG was correlated with self-rated performance. This study found no

relationships between variables and fight result, suggesting that predicting the

results of MMA competition may be complex and beyond the scope of this study

protocol.

Limitations

Recognizing the limitations of the present study is important when

highlighting its implications for practice and future research. Analyzing the

independent role of each predictor variable for the dependent variables punching

velocity, fight result, and self-rated performance was difficult due to the small

sample size. Utilizing Chi-square analyses was not most appropriate, given the

distribution of subjects within the cross-tabulations. However, by providing LRT

and Cramer’s V calculations, the present study utilized an alternative test that was

appropriate for describing the effects and answering the research questions while

55
also describing the statistical strength and significance of the correlations

observed. A larger sample have would allowed for the use of regression analyses

to measure the independent associations between predictors and outcomes related

to rapid weight loss in combat sports. The present study did not include

parameters related to training load and subsequent recovery, technical skill-level,

fasting-adaptions, or specific dietary approaches that may yield benefits to

fighters practicing RWL. A larger sample with more-comprehensive parameters

would have provided more valid estimations of the effects diet, hydration,

training, and body composition have on performance markers among combat

sports athletes. However, the present study provides novel insights into

relationships between nutrition, fasting, hydration, body composition, and athletic

performance among a sample of MMA fighters going through a natural, non-

simulated, cycle of rapid weight loss and refeeding prior to competition.

Conclusion

This study observed a sample of MMA fighters reducing body mass by 5-

12% during a six-day time period in order to meet the weight requirements for

competition. Only one participant did not display a USG in the abnormal range at

the time of weigh-ins, suggesting that MMA fighters deny their bodies fluids to a

56
point of clinical dehydration. Each participant in this study utilized fasting to

reduce body mass. While almost all participants fasted for periods between 19

and 27 hours, two MMA fighters in the sample utilized very long fasting periods

of greater than 60 hours. There may be between-group differences in the impact

of fasting on performance due to metabolic adaptations to longer adaptations.

Chi-square analysis revealed a statistically significant relationship between

fasting periods of less than 24 hours and improved punching velocity. These

findings have significant implications for combat sports athletes and coaches

seeking competitive advantages through the utilization of RWL. However, larger

studies would be required to describe the association between dietary behaviors,

hydration, and fasting as they relate to athletic performance. After qualifying for

competition in their respective weight-class, combat sports athletes “refeed” in an

attempt to refill glycogen stores and achieve euhydration prior to competition, a

timeframe of 26-30 hours for the participants in this study. Most participants in

the sample achieved euhydration after refeeding. While larger future studies with

more robust measuring protocols are required to identify definitive predictors of

performance, beyond punching velocity, this study utilized a novel approach and

observed significant relationships with practical implications for athletes and

57
coaches in combat sports. Specifically, these findings suggest athletes and

coaches in combat sports may be able to utilize RWL-refeeding cycles to improve

athletic performance after significant RWL of 5-12% body mass.

Future studies should aim to recruit larger samples of fighters from

various disciplines of combat sports to address the wide array of factors

associated with athletic performance. Despite the findings of the present study

suggesting improvements to athletic performance can be achieved after RWL-

refeeding cycles, research has yet to place scrutiny on the implications of RWL-

refeeding cycles on athlete health, particularly acute cardiac changes. Further

evaluation of the safety of this practice is required, but the findings from this

study suggest that shorter fasting periods, less than 24 hours, may yield substrate-

level metabolic benefits as well as improvements to athletic performance markers

when compared to fighters who utilize fasting periods greater than 24 hours.

58
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LIST OF APPENDICES

97
APPENDIX A: INVITATION TO PARTICIPATE

98
Dear [Gym/Owner Name]

I'm hopeful that your fight promotion can contribute to my dissertation research at
the University of Mississippi. I am Katie Halfacre-Cunningham, and I am a PhD
student in the Department of Nutrition and Hospitality Management. I'm a
lifelong fan of martial arts and have developed an exciting study design to
observe the impact of nutrition and hydration on the performance of fighters as
they go through the fight-week weight cut. It is a non-invasive study, and I'd be
happy to share more information regarding the study design if you are interested.

Primarily, I need access to fighters to conduct my research. I was hoping that,

with your assistance, I could reach out to fighters competing in your promotion to
request their participation in this study. Your assistance in getting in touch with
fighters would be greatly appreciated. You can reach me via email at this address
(klhalfac@go.olemiss.edu) and phone (662-705-1292). If you try to give me a
call, I may be in class or giving a lecture, but I will get back to you ASAP. I look
forward to hearing from you soon.

99
APPENDIX B: INFORMED CONSENT

100
 Consent to Participate in Research
Making the Cut: Nutrition and Hydration Practices among MMA Fighters

Investigator Faculty Sponsor

Katharine Halfacre, PhD Student, M.S. Kathy Knight, PhD, RD
Department of Nutrition & Hosp. Mgmt. Department of Nutrition &
Hosp. Mgmt.
116 Lenoir Hall 201 Lenoir Hall
University of Mississippi University of Mississippi
University, MS 38677 University, MS 38677
(662) 705-1292 (662) 915-5172
klhalfac@go.olemiss.edu kknight@olemiss.edu

Key Information for You to Consider

 Purpose. The purpose of this research is to determine how changes
in hydration, dietary intake, supplement usage, and body
composition are associated with athletic performance after rapid
weight loss and refeeding among MMA fighters.
 Duration. It is expected that your participation will last a week.
You will participate in two one-hour sessions, the first being 7-10
days prior to competition and the second being on the day of
competition. You will need to provide a urine sample prior to
weigh-ins. Your total participation will require about 2 hours and 5
minutes over the course of the fight week.
 Activities. You will be asked to do the following: have your body
composition analyzed twice; provide three (3) urine samples; use
wearable technology to perform punches and jumps on two (2)
occasions; and provide a food/supplement journal during or after
your week of preparation for competition.
 Why you might not want to participate. Some of the foreseeable
risks or discomforts of your participation include the assessment of
body composition which requires pinching of the skinfolds which is
mildly painful.

101
  Why you might want to participate. Some of the benefits that
may be expected include knowledge of your body composition and
athletic performance. You may gain insight into your nutrition,
hydration, and weight-loss practices during a weight cut. You will
be contributing to the scientific knowledge regarding weight-cutting
in MMA fighters.

You are being asked to volunteer for a research study. It is up to you

whether you choose to participate or not. There will be no penalty or loss of
benefits to which you are otherwise entitled if you choose not to participate or
discontinue participation.
Combat sports competitions such as mixed martial arts (MMA) are often
separated into weight divisions. These weight-classes motivate fighters to gain a
competitive edge through rapid weight loss (RWL). This practice has been linked
to hospitalizations and deaths. Research into the health and performance
implications is warranted. The goal of this study is to determine how changes in
hydration, dietary intake, supplement usage, and body composition are associated
with athletic performance after RWL and refeeding among elite MMA fighters.

By checking this box I certify that I am 18 years of age or older.

What you will do for this study

This study is a non-invasive measurement of various functions of your
body, with the intention of gaining a better scientific understanding of the fight-
week weight cut among MMA fighters. You will have your height, weight,
skinfolds, and bone girths measured by a certified anthropometrist. This will be
done 7-10 days prior to competition and on the day of competition. You will
provide urine samples 7-10 days prior to competition, on weigh-in day, and after
refeeding (on the day of competition). You will be asked to briefly wear a devise
to assess your punch force 7-10 days prior to competition and on the day of
competition. You will be asked to perform a counter-movement vertical jump to
assess the force generated by your lower body. During the week after

102
competition, you will be asked to provide a food journal and respond to a 10-
question survey. The survey will assess your feelings about the fight-week weight
cut you underwent, your performance, and other attitudes regarding the weight-
cut process. In the food journal, in addition to providing information regarding
your dietary intake, you will be asked to describe the weight-cutting strategies
(sauna, sauna suit, diuretics) and supplements that you used during the fight-week
weight cut.

Time required for this study

Day 1 will take about 1 hour. Weigh-in day will only require about 5
minutes. Participation after refeeding will take about 1 hour. Total time required
should be 2 hours and 5 minutes.

Possible risks from your participation

No significant risks but the pinching of skinfolds is mildly painful.

Benefits from your participation

You should not expect any direct benefits from participating. However,
you will be contributing to scientific knowledge about weight cutting in your
sport. You may also gain insight into your athletic performance (punch force and
lower body force) and attitudes regarding weight cuts.

Confidentiality
Research team members will have access to your records. Your
confidentiality will be protected by coding and separating the information that
identifies you from your responses. Members of the Institutional Review Board
(IRB) – the committee responsible for reviewing the ethics of, approving, and
monitoring all research with humans – have authority to access all records.
However, the IRB will request identifiers only when necessary. We will not
release identifiable results of the study to anyone else without your written
consent unless required by law.

103
Right to Withdraw
You do not have to volunteer for this study, and there is no penalty if you
refuse. If you start the study and decide you do not want to finish, or you would
like to opt out of one part of the study, then just tell the experimenter. Your
decision to participate or abstain from participation will not affect your current or
future relationship with the Department of Nutrition and Hospitality
Management, or with the University of Mississippi, and it will not cause you to
lose any benefits to which you are entitled.

Collection of Identifiable Private Information or Identifiable Biospecimens

Identifiers might be removed from your identifiable private information
and your identifiable biospecimens (urine samples) such that your information
and biospecimens collected as a part of this research will not be used or
distributed for future research studies.

IRB Approval
This study has been reviewed by The University of Mississippi’s
Institutional Review Board (IRB). The IRB has determined that this study fulfills
the human research subject protections obligations required by state and federal
law and University policies. If you have any questions or concerns regarding
your rights as a research participant, please contact the IRB at (662) 915-7482 or
irb@olemiss.edu.

Please ask the researcher if there is anything that is not clear or if you need more
information. When all your questions have been answered, then decide if you
want to be in the study or not.

Statement of Consent
I have read the above information. I have been given an unsigned copy of this
form. I have had an opportunity to ask questions, and I have received answers. I
consent to participate in the study.

104
Furthermore, I also affirm that the experimenter explained the study to me and
told me about the study’s risks as well as my right to refuse to participate and to
withdraw.

Signature of Participant Date

Printed name of Participant

105
 VITA

KATHARINE L. HALFACRE

EDUCATION

Bachelor of Science in Kinesiology with a concentration in Health Fitness

Studies, Mississippi State University, December 2014, magna cum laude

Master of Science in Food & Nutrition Services, University of Mississippi,

Oxford, MS, May 2017, Master’s Thesis: Diet Quality and Food

Insecurity among University Students: The Role of Food Preparation

Ability

EMPLOYMENT

Institute of Child Nutrition

Aug. 2015 to May 2016 Graduate Administrative Assistant

Department of Athletics, Sports Nutrition

July 2019 to Jan. 2020 Graduate Research Assistant

106
Department of Nutrition and Hospitality Management

Jan. 2017 to Present Graduate Instructor

Aug. 2016 to Present Graduate Teaching Assistant

HONORS AND AWARDS

2017 Featured (top-4) poster presentation at the Wellness and Public

Health educational session of the Academy of Nutrition and

Dietetics Food and Nutrition Conference & Expo

2017 Outstanding Abstract at Academy of Nutrition and Dietetics Food

and Nutrition Conference & Expo

2014 Graduated with honors, magna cum laude, Mississippi State

University

107