Mixed Martial Arts Research Articles

The Physiological and Morphological Benefits of Shadowboxing

Is shadowboxing an effective form of functional exercise? What physiological and morphological changes result from an exercise program based exclusively on shadowboxing for 3 weeks? To date, no empirical research has focused specifically on addressing these questions. Since mixed martial arts (MMA) is the fastest growing sport in the world, and since boxing and kickboxing fitness classes are among the most popular in gyms and fitness clubs worldwide, the lack of research on shadowboxing and martial arts-based fitness programs in the extant literature is a shortcoming that the present article aims to address. This case study involved a previously sedentary individual engaging in an exercise program based exclusively on shadowboxing for 3 weeks. Body composition and heart rate data were collected before, throughout, and upon completion of the 3-week exercise program to determine the effectiveness of shadowboxing for functional fitness purposes. An original shadowboxing program prepared by an Everlast Master Instructor and NASM Certified Personal Trainer (NASM-CPT) and Performance Enhancement Specialist (NASM-PES) was used for this 3-week period. The original shadowboxing program with goals, techniques, and combinations to work on throughout the 3-week program is included in this article. This case study demonstrates that a 3-week exercise program based exclusively on shadowboxing can increase aerobic capacity, muscle mass, bone mass, basal metabolic rate, and daily calorie intake, and decrease resting heart rate, fat mass, body fat percentage, and visceral fat rating in a previously sedentary individual. The results of this research demonstrate that shadowboxing can be a safe and effective form of exercise leading to morphological and physiological improvements including fat loss and increased aerobic capacity. The results of this research also demonstrate that the Tanita BC-1500 is a reliable tool for individuals to evaluate their own fitness progress over time.

Effects of Probiotics and Vitamin D3 Supplementation on Sports Performance Markers in Male Mixed Martial Arts Athletes: A Randomized Trial

BackgroundStrategies targeted at the intestine microbiome seem to be beneficial for professional athletes. The gut–muscle axis is associated with the inflammatory state, glucose metabolism, mitochondrial function, and central nervous system health. All these mechanisms may affect maximal oxygen uptake, muscle strength, and training adaptation. Moreover, the positive effect of certain bacterial strains may be enhanced by vitamin D. Thus, this study aimed to assess and compare the level of selected markers of sports performance of mixed martial arts (MMA) athletes supplemented with vitamin D3 or probiotics combined with vitamin D3.MethodsA 4-week randomized double-blind placebo-controlled clinical trial was conducted with 23 MMA male athletes assigned to the vitamin D3 group (Vit D; n = 12) or probiotics + vitamin D3 group (PRO + VitD; n = 11). Repeated measures of the creatine kinase level, lactate utilization ratio, and anaerobic performance were conducted.ResultsAfter 4 weeks of supplementation, we found lower lactate concentrations 60 min after the acute sprint interval in the PRO + VitD group when compared to the Vit D group (4.73 ± 1.62 and 5.88 ± 1.55 mmol/L; p < 0.05). In addition, the intervention improved the total work (232.00 ± 14.06 and 240.72 ± 13.38 J kg−1; p < 0.05), and mean power following the anaerobic exercise protocol (7.73 ± 0.47 and 8.02 ± 0.45 W kg−1; p < 0.05) only in the PRO + VitD group. Moreover, there was an improvement in the lactate utilization ratio in the PRO + VitD group compared with the Vit D group as shown by the percentage of T60/T3 ratio (73.6 ± 6.9 and 65.1 ± 9.9%, respectively; p < 0.05). We also observed elevated serum 25(OH)D3 concentrations after acute sprint interval exercise in both groups, however, there were no significant differences between the groups.ConclusionFour weeks of combined probiotic and vitamin D3 supplementation enhanced lactate utilization and beneficially affected anaerobic performance in MMA athletes.

The legalization process of mixed martial arts and its effects on both practice and practitioners: The case of France

As a genuinely contemporary sport, mixed martial arts (MMA) was born and developed throughout the twentieth century, during which time it remained fairly marginal, only to find a more formal and mediatized format in the 1990s. The first legal events in France began taking place in 2020. Consequently, how did legalization influence the evolution of MMA practice, both in training rooms and during competitions? The research is primarily based on 21 semi-directive interviews and the observation of five events (pankration/kempo rules) in France, between 2011 and 2015. The last step included the legalization phase of the sport between 2019 and 2022 and four professional events observed in France (MMA rules). Ten interviews were carried out with federal or organizational figures, in addition to trainers and fighters. The main result shows that MMA in France was already sportivized before legalization. Legalization tends to reassure individuals and parents.

Combat Sports as a Model for Measuring the Effects of Repeated Head Impacts on Autonomic Brain Function: A Brief Report of Pilot Data.

Automated pupil light reflex (PLR) is a valid indicator of dysfunctional autonomic brain function following traumatic brain injury. PLR's use in identifying disturbed autonomic brain function following repeated head impacts without outwardly visible symptoms has not yet been examined. As a combat sport featuring repeated 'sub-concussive' head impacts, mixed martial arts (MMA) sparring may provide a model to understand such changes. The aim of this pilot study was to explore which, if any, PLR variables are affected by MMA sparring. A cohort of n = 7 MMA athletes (age = 24 ± 3 years; mass = 76.5 ± 9 kg; stature = 176.4 ± 8.5 cm) took part in their regular sparring sessions (eight rounds × 3 min: 1 min recovery). PLR of both eyes was measured immediately pre- and post-sparring using a Neuroptic NPi-200. Bayesian paired samples t-tests (BF10 ≥ 3) revealed decreased maximum pupil size (BF10 = 3), decreased minimum pupil size (BF10 = 4) and reduced PLR latency (BF10 = 3) post-sparring. Anisocoria was present prior to sparring and increased post-sparring, with both eyes having different minimum and maximum pupil sizes (BF10 = 3-4) and constriction velocities post-sparring (BF10 = 3). These pilot data suggest repeated head impacts may cause disturbances to autonomic brain function in the absence of outwardly visible symptoms. These results provide direction for cohort-controlled studies to formally investigate the potential changes observed.

Physician attitudes toward sports medicine coverage of mixed martial arts.

The popularity of modern Mixed Martial Arts (MMA) has been increasing since 2000s. It has drawn the attention of the media due to higher injury rates compared to other sports, and it is possible that this may have led to a generally negative image of MMA among viewers, including but not limited to, physicians. Therefore, our study aimed to understand the attitudes of physicians toward MMA and being asked to cover MMA events. A cross-sectional study with an online survey was answered by 410 physicians from four physician organizations throughout the USA. Demographic data, sports event-related, sports coverage experience, athleticism, and familiarity with MMA answers were analyzed. Wilcoxon, Fisher Exact, and χ2 tests were used to compare the data. The main outcomes was the association between characteristics of physicians and attitude toward MMA coverage. Physician characteristics influenced positive attitudes toward MMA coverage. Those who regularly followed MMA felt more strongly that combat sport events required physician coverage, mainly for boxing (92.4% vs. 73.4%; P<0.001), kickboxing (89.9% vs. 54.7%; P<0.001), and taekwondo (50.6% vs. 38.4%; P=0.046). Doctors who considered themselves athletic or who had covered MMA events in the past were more likely to think that all sporting events should be covered by physicians (97.4% vs. 65.9%; P<0.01; 98.4% vs. 72.8%, P<0.001, respectively). Family medicine (72/139 [51.8%]) and physical medicine and rehabilitation (7/11 [63.6%]) were the specialties more inclined to agree with physician coverage for these events. Physicians familiar with MMA, either as a previous ringside physician or as a spectator, are more inclined to believe these events should have physician coverage as are those more experienced with sports medicine, such as family medicine and physical medicine and rehabilitation specialists. Therefore, specialized sports medicine training should be provided to allow for appropriate MMA physician coverage. With additional training, MMA event organizers should feel comfortable asking physicians in any specialty to provide sports medicine coverage to improve care for MMA athletes.

Match-related performance in mixed martial arts athletes: a technical variability analysis

Match-related performance in mixed martial arts athletes: a technical variability analysis

An Attempt to Develop a Model of Brain Waves Using Quantitative Electroencephalography with Closed Eyes in K1 Kickboxing Athletes-Initial Concept.

Brain injuries are a common problem in combat sports, especially in disciplines such as kickboxing. Kickboxing is a combat sport that has several variations of competition, with the most contact-oriented fights being carried out under the format of K-1 rules. While these sports require a high level of skill and physical endurance, frequent micro-traumas to the brain can have serious consequences for the health and well-being of athletes. According to studies, combat sports are one of the riskiest sports in terms of brain injuries. Among the sports disciplines with the highest number of brain injuries, boxing, mixed martial arts (MMA), and kickboxing are mentioned. The study was conducted on a group of 18 K-1 kickboxing athletes who demonstrate a high level of sports performance. The subjects were between the ages 18 and 28. QEEG (quantitative electroencephalogram) is a numeric spectral analysis of the EEG record, where the data is digitally coded and statistically analysed using the Fourier transform algorithm. Each examination of one person lasts about 10 min with closed eyes. The wave amplitude and power for specific frequencies (Delta, Theta, Alpha, Sensorimotor Rhythm (SMR), Beta 1, and Beta2) were analysed using 9 leads. High values were shown in the Alpha frequency for central leads, SMR in the Frontal 4 (F4 lead), Beta 1 in leads F4 and Parietal 3 (P3), and Beta2 in all leads. The high activity of brainwaves such as SMR, Beta and Alpha can have a negative effect on the athletic performance of kickboxing athletes by affecting focus, stress, anxiety, and concentration. Therefore, it is important for athletes to monitor their brainwave activity and use appropriate training strategies to achieve optimal results.

Suggestions for Professional Mixed Martial Arts Training With Pacing Strategy and Technical-Tactical Actions by Rounds.

Antoniettô, NR, Bello, FD, Carrenho Queiroz, AC, Berbert de Carvalho, PH, Brito, CJ, Amtmann, J, and Miarka, B. Suggestions for professional mixed martial arts training with pacing strategy and technical-tactical actions by rounds. J Strength Cond Res XX(X): 000-000, 2019-This study compared the pacing strategy and motor actions used in mixed martial arts combats ending by knockout/technical knockout (KO/TKO) or submission. All of the sample bouts ended in KO/TKO and consisted of 1,564 rounds of 678 bouts. The bouts were separated by round (R) of bouts ending (ER) in the first round (n = 192), first (1R × 2ER) and second (2R × 2ER) of bouts ending in the second round (n = 172), and first (1R × 3ER), second (2R × 3ER), and third (3R × 3ER) of bouts ending in the third round (n = 1,200). The analyses were performed according to the duration ([INCREMENT]) in each phase: [INCREMENT] standing preparatory activity time, [INCREMENT] standing combat activity time, [INCREMENT] ground preparatory activity time, and [INCREMENT] ground combat activity time and their technical-tactical actions (attempted and landed strikes to the head, body and leg, takedowns, and submissions). The main results demonstrated a shorter [INCREMENT] standing preparatory activity time in 1R × 1ER (95.6 ± 62.9 seconds) and 2R × 2ER (93.6 ± 67.9 seconds) vs. 2R × 3ER (160.5 ± 87.4 seconds) and 3R × 3ER (144.0 ± 88.5 seconds) with fewer strikes attempted and landed to the head, body, and legs (p ≤ 0.05). No differences were observed (p > 0.05) between [INCREMENT] standing combat activity time, but lower attempted and landed takedowns and strikes to the head, body, and leg frequencies. There were shorter [INCREMENT] ground combat activity time (p ≤ 0.05) in 1R × 1ER (23.4 ± 45.5) and 2R × 2ER (25.3 ± 41.9) vs. 2R × 3ER (50.4 ± 69.9) and 3R × 3ER (52.9 ± 74.2), with lower attempted submissions, chokes, and attempted and landed strikes to the head, body, and leg frequencies observed. These results contribute to the information developed from current research to help improve the quality of training and promote effective athletic preparation related to pacing strategy and performance models.

A comparison of physiological intensity and psychological perceptions during three different group exercise formats.

Past research highlighted that group fitness is an ideal format to meet exercise prescription guidelines. To add, a group enhances exertion, enjoyment, and satisfaction. In the last five years, streaming (live classes on screen with other participants visible) and on demand (pre-recorded classes on screen without other participants visible) formats have grown in popularity. Our goal is to compare the physiological intensity and psychological perceptions of live group, live streaming, and non-live on demand classes. We hypothesize that live classes will have the greatest cardiovascular intensity, enjoyment, and satisfaction followed by streaming and finally on demand. Fifty-four adults between 18-63 years, who regularly participate in group fitness classes, recorded their heart rate with a chest transmitter during a mixed-martial arts cardiovascular class on consecutive weeks in random order. We calculated the mean, identified the max, and extracted the top 300 values (5 min) for comparison between conditions. Following each class, the participants completed an online survey to evaluate their rate of perceived exertion, enjoyment, and satisfaction. Confirming our hypothesis, mean class heart rate and mean heart rate for the five minutes at the highest intensity were 9% greater during the live group format compared to both live streaming and non-live on demand (all values, p < 0.01). However, there was no difference in any heart rate variables between the streaming and on demand formats. Also, rate of perceived exertion, enjoyment, and satisfaction were all significantly greater during the live session compared to the home collections (all values, p < 0.05). Streaming and on demand group fitness formats are viable options for meeting exercise prescription guidelines. But physiological intensity and psychological perceptions were greater during the live class format.

Sparring and the Brain: The Associations between Sparring and Regional Brain Volumes in Professional Mixed Martial Arts Fighters.

Mixed martial arts (MMA) fighters, due to exposure to repetitive head impacts, are at risk for brain atrophy and neurodegenerative sequelae. Simultaneously, motor skills training and cognition-rich activities have been linked with larger regional brain volumes. The majority of an MMA fighter's sporting activity occurs during practice (e.g., sparring) rather than formal competition. This study, therefore, aims to be the first to explore regional brain volumes associated with sparring in MMA fighters. Ninety-four active, professional MMA fighters from the Professional Fighters Brain Health Study met inclusion criteria for this cross-sectional analysis. Adjusted multivariable regression analyses were utilized to examine the relationship between the number of sparring practice rounds per week during typical training and a select number of regional brain volumes (i.e., caudate, thalamus, putamen, hippocampus, amygdala). A higher number of weekly sparring rounds during training was significantly associated with larger left (beta = 13.5µL/round, 95%CI 2.26-24.8) and right (beta = 14.9µL/round, 95%CI 3.64-26.2) caudate volumes. Sparring was not significantly associated with left or right thalamus, putamen, hippocampus, or amygdala volumes. More weekly rounds of sparring was not significantly associated with smaller volumes in any of the brain regions studied in active, professional MMA fighters. Sparring's significant association with larger caudate volume raises questions about whether fighters who spar more experience attenuated trauma-related decreases in caudate volume relative to fighters who spar less, whether fighters who spar more experience minimal or even positive changes to caudate volume, whether baseline differences in caudate size may have mediated results, or whether some other mechanism may be at play. Given limitations inherent to the cross-sectional study design, more research is needed to further explore the brain effects of sparring in MMA.

Predicting MMA leagues’ fan involvement through its brand credibility and league-brand associations

ABSTRACT Purpose: With the fast-paced growth of MMA (mixed martial arts) globally as an individual-based sport, MMA leagues are required to develop their fans’ involvement with the brand. Design: (N = 416) fans’ responses were collected at the UFC Fight Night in Abu Dhabi. Findings: This research measured how MMA leagues’ brand association can predict MMA brand credibility through SEM and found that star athletes and group experience have a positive impact on brand credibility, but nostalgia and atmosphere were found to be insignificant. Moreover, brand credibility was found as a positive predictor of brand involvement. Originality: This empirical research contributes to sports marketing literature by defining the brand associations of athlete-based sports leagues, and by showing the positive impact of the league’s brand credibility on its fans’ brand involvement. Implications: The novel framework can serve as a blueprint or guideline for organizations in the MMA sector to gain a competitive edge by providing a clear and structured understanding of the industry, identifying the key concepts and relationships that underpin the art of branding, better recognizing opportunities for growth and diversity, and developing more effective strategies and tactics.

Machine-learning-based head impact subtyping based on the spectral densities of the measurable head kinematics

BackgroundTraumatic brain injury can be caused by head impacts, but many brain injury risk estimation models are not equally accurate across the variety of impacts that patients may undergo, and the characteristics of different types of impacts are not well studied. We investigated the spectral characteristics of different head impact types with kinematics classification. MethodsData were analyzed from 3262 head impacts from lab reconstruction, American football, mixed martial arts, and publicly available car crash data. A random forest classifier with spectral densities of linear acceleration and angular velocity was built to classify head impact types (e.g., football, car crash, mixed martial arts). To test the classifier robustness, another 271 lab-reconstructed impacts were obtained from 5 other instrumented mouthguards. Finally, with the classifier, type-specific, nearest-neighbor regression models were built for brain strain. ResultsThe classifier reached a median accuracy of 96% over 1000 random partitions of training and test sets. The most important features in the classification included both low- and high-frequency features, both linear acceleration features and angular velocity features. Different head impact types had different distributions of spectral densities in low- and high-frequency ranges (e.g., the spectral densities of mixed martial arts impacts were higher in the high-frequency range than in the low-frequency range). The type-specific regression showed a generally higher R2 value than baseline models without classification. ConclusionThe machine-learning-based classifier enables a better understanding of the impact kinematics spectral density in different sports, and it can be applied to evaluate the quality of impact-simulation systems and on-field data augmentation.

In search of muscular fitness and its relation to training experience and sports performance of athletes of modern combat sports such as mixed martial arts (MMA) and Brazilian jiu-jitsu (BJJ)

Background: Combat sports, including MMA and BJJ place very high and varied demands on athletes in terms of strength and strength-endurance training. The aim of the present study was to level of development motor fitness athletes combat sports and examine their relationship with training experience, and high sports performance. Methods: Thirty athletes were studied and compared between two groups: MMA (N=15) and BJJ (N=15). Somatic measurements were performed. Selected manifestations of the athlete’s potential in terms of strength and strength endurance were also measured, using selected tests from the International Physical Fitness Test (EUROFIT) battery, and relative strength and MAW indices were calculated. A coach ranking of athletes by sports achievement was developed. Next, the strength of the relationship of the effect of the aspects of strength and conditioning with training experience and sports performance was assessed. Results: The level of motor fitness in the groups was significantly different between the athletes of these sports in terms of strength and strength endurance abilities (p=0.006-0.038). A higher level of these elements of fitness was displayed by BJJ athletes. In both groups, significant correlations were found between the motor effect and the training experience (r=0.53-0.89) also sports result (r=0.53-0.76). Conclusions: The results allow for the initial diagnosis and interpretation of motor fitness competencies along with the profile of its key manifestations in MMA and BJJ, which promotes optimization of the quality of coaching control.

The Emergence of Mixed Martial-Arts and the Future of Boxing: An Analysis of Consumer Interest and Compensation

Despite its long-standing history as the most popular and mainstream combat sport, boxing has been confronted with increased competition from mixed martial arts (MMA) in recent decades. The dominant organization in the MMA market, the Ultimate Fighting Championship (UFC), has grown to become a multibillion dollar organization. In this article, we directly compare consumer interest and fighter compensation between boxing and the UFC to consider the economic potential for these combat sports into the future. Overall, our conclusions indicate that boxing has continued to be more lucrative as a whole, with the key factor being the presence of superstar athletes.

Physical Philosophy: Martial Arts as Embodied Wisdom

While defining martial arts is not prerequisite to philosophizing about them, such a definition is desirable, helping us resolve disputes about the status of hard cases. At one extreme, Martínková and Parry argue that martial arts are distinguished from both close combat (as unsystematic) and combat sports (as competitive), and from warrior arts (as lethal) and martial paths (as spiritual). At the other extreme, mixed martial arts pundits and Bruce Lee speak of combat sports generally as martial arts. I argue that the fine-grained taxonomy proposed by Martínková and Parry can be usefully supplemented by a broader definition, specifically the following: martial arts are systematic fighting styles and practices as ways of embodying wisdom. A possible difficulty here is that such views face the charge of overemphasizing the “philosophical” aspect of martial arts. My definition can, however, avoid this apparent problem. If martial arts essentially aim to embody wisdom, this applies no less to the (strategic) practical wisdom of The Art of War than to the (ethical) practical wisdom of the Tao Te Ching. In an extended sense, then, any systematic fighting style, including combat sports, may count as a martial art insofar as it embodies wisdom by improving practical fighting skills.

Dysregulation of miR-155 Expression in Professional Mixed Martial Arts (MMA) Fighters.

Psychological and physical stress can induce dysregulation of gene expression via changes in DNA methylation and microRNA (miRNA) expression. Such epigenetic modifications are yet to be investigated in professional Mixed Martial Arts (MMA) fighters subject to highly stressful training involving repetitive head impacts. This study examined differences in DNA methylation and miRNA expression in elite MMA fighters compared to active controls. Global methylation differences between groups were assessed via a LINE-1 assay. At the same time, PCR arrays were used to estimate differential expression in samples of 21 fighters and 15 controls for 192 different miRNAs associated with inflammatory diseases. An Independent-Samplest-Test found no significant difference in LINE-1 methylation between groups. However, an Independent-Samples Mann-Whitney U Test revealed a significant upregulation in the expression of miR-155 in MMA fighter plasma. Since miR-155 has been recognized as an important regulator of neuroinflammation, this dysregulation suggests a possible epigenetic mechanism responsible for chronic inflammation associated with professional-level MMA training. Consistent with other published works, this study highlights the potential of miR-155 not only as a biomarker for monitoring long-term health risks linked to head trauma but also as a target to remediate the impact of chronic neuroinflammation.

Mixed Martial Arts Discourse from the Perspective of its Entertaining Nature and Figurativeness

The article dwells on mixed martial arts discourse which is interpreted as a type of martial discourse dealing with sports communication and having an entertaining quality, thus allowing us to speak of a hybrid discourse. The methodology of this research includes descriptive and analytical methods. The linguostylistic and contextual types of analysis alongside with the quantitative method have been applied. The most common key concepts related to interactive communication have been singled out: ‘game’, ‘fun’, ‘show’, ‘entertainment’, ‘performance’, ‘pleasure’, etc. All of them play an important role in mixed martial arts discourse and manifest themselves in its lexis. We have also found that one of the most important tropes used in sports communication is the metaphor. In mixed martial arts discourse, many metaphorical models are actualized. The main one is the military metaphor. This is accounted for by profound kinship between mixed martial arts, the battle, the fight and the war. In our material, a zoomorphic metaphor is the second most frequent one. Reference to the animal world is underpinned by drawing a parallel between animal and human aggression. A professional mixed martial artist has to be dangerous and belligerent. Hence, the metaphorical likening of them to the hunter and to some extent to someone disturbing public order or even breaking the law, that is what our analysis shows. It was also found that a mixed martial arts champion is often portrayed as the king (or the queen as the case may be).

Mixed Martial Arts As a Way of Life: Going Beyond The Black Belt And Engaging in Life-Long Learning

In this qualitative study, we explored the experiences of 10 adults who trained in mixed martial arts (MMA) to understand the meaning they ascribed to attaining the black belt and their martial arts journal overall. Using a conventional content analysis, four themes were derived from the data: importance of the black belt, benefits of training in MMA, dealing with injuries, and being part of the MMA community. Training in MMA was very positive, with both individual benefits (improved physical and mental health, skill development, and personal growth) and interpersonal benefits (relationship development and sense of community) being reported. Self-determination theory (Ryan &amp; Deci, 2000) and goal setting theory (Locke &amp; Latham, 2002) are used to discuss participants’ motivation in their pursuit of the black belt and continued training.

MMA and the purist/partisan distinction

ABSTRACT The purist/partisan distinction has dominated recent discussions of sport spectatorship and sport aesthetics. The focus of such discussions, however, has been sport in general or, often implicitly, team sports in particular. Here, using mixed martial arts (MMA) as a case study, we argue that specific aspects of the sport in question can significantly affect how the purist/partisan distinction plays out for viewers. MMA’s status as an individual combat sport mitigates, in illuminating ways, the partisanship displayed so prominently among fans of team sports. We also examine the role of external attitudes – in both the betting subculture of MMA and purist attitudes toward individual combat sports and martial arts – in shaping MMA spectatorship.

Rapid Weight Gain and Weight Differential Predict Competitive Success in 2100 Professional Combat-Sport Athletes.

Combat-sport athletes commonly undergo rapid weight loss prior to prebout weigh-in and subsequently rapid weight gain (RWG) prior to competition. This investigation aimed to evaluate the effect of RWG and weight differential (WD) between opponents on competitive success. A retrospective cohort study was performed using data from professional mixed martial arts (MMA) and boxing events held between 2015 and 2019. The primary outcome was RWG (relative and absolute) between weigh-in and competition stratified by bout winners and losers. Binary logistic regression was used to explore the relationships among bout outcome, RWG, and WD between competitors on the day of their bout. Among 708 MMA athletes included, winners regained more relative body mass (8.7% [3.7%] vs 7.9% [3.8%], P < .01) than losers. In 1392 included male boxers, winners regained significantly more relative body mass (8.0% [3.0%] vs 6.9% [3.2%], P < .01) than losers. Each percentage body mass increase resulted in a 7% increased likelihood of victory in MMA and a 13% increase in boxing. The relationship between RWG and competitive success remained significant in regional and male international MMA athletes, as well as boxers. WD predicted victory in international mixed martial artists and boxers. WD predicted victory by knockout or technical knockout in international MMA athletes and regional boxers. This analysis of combat-sport athletes indicates that RWG and WD influence competitive success. These findings raise fair-play and safety concerns in these popular sports and may help guide risk-mitigating regulation strategies.