Mixed martial arts (MMA) competition spans 10 weight divisions (27), and fighters often engage in strategies to reduce as high as 10% body weight in the 2–3 days before weigh-in (10,11,15,16,20,37). Weight-making strategies include intentional hypohydration (35), starvation (4), exercising in plastic or rubber suits, saunas, and fluid intake restriction (34). Despite the severity of such strategies, fighters hold positive beliefs that weight can be replaced after the weigh-in, giving a weight advantage over her or his opponent in competition (15,29).
Wide scale usage of rapid weight loss (RWL) strategies should be seen in context of evidence that shows they impair physical capacity for performance. Impaired performance occurs via factors associated with moderate dehydration that can impair muscular endurance during high-intensity exercise (19). Dangerous dehydration can result in a reduction of plasma volume, stroke volume, an increase in heart rate, and reduced arteriovenous oxygen difference during submaximal workouts (17). These modifications can affect renal flow and electrolyte abnormalities, and athletes who use rapid weight-making strategies are vulnerable to heat injury and muscle cramps (36). Usage of rapid weight-making strategies can also have negative health consequences (4), including acute effects on hormonal changes, growth impairment, poor bone formation, and reduced basal metabolic rate (2,32,36). Rapid weight loss is also associated with negative feelings, such as increased anger, confusion, depression, fatigue, and tension (15). Mood and emotions are commonly regarded as important precompetitive indicators of performance in competition (5,14,21,22). A positive mood profile is proposed to assist positive management of thoughts, feelings, and behaviors before and during competition (7,22).
Despite these negative findings, not all research has been so clear-cut. From a study of 28 well-trained combat athletes (wrestling, boxing, judo, taekwondo, and karate athletes), Reljic et al. (38) reported no significant change in aerobic performance capacity in the RWL group when compared with a control group. Hall and Lane (15) found no significant difference in performance between competition and normal weight in a sample of competitive boxers.
It should be noted that little is known about the mood in MMA fighters. To address this gap in the research, the present study set out to explore changes in mood states and body weight in MMA fighters over the month leading up to competition and then investigate the association with RWL and performance. We argue that the first step should be an exploratory study to explore mood and body weight at different points in time leading to competition. A study about mood state and body weight modifications in MMA will inform future research and practice on the most appropriate research design and data collection methods to follow. Mood is transient in nature, and precompetitive mood is influenced by a variety of factors, including features of the precompetitive period (e.g., the surrounding environment). On the day of competition, the quality of the opponent could have a significant influence on the mood state of the fighter. Competing against an unknown opponent but one with a better ranking could exacerbate any personal concerns that the player might have (7). It is argued that the mood states of athletes going into competition could influence performance. For example, during 4–5 minutes per round, it is proposed that intense emotional arousal, such as feeling vigorous, could help fighter's decision-making speed (30). Fast decision-making should enhance full contact striking skills, grappling actions, submissions, chokes, and joint locking techniques (31).
Even though there is widespread acknowledgment of the significance of mood states in sports performance (5) and overall health (1), relatively little is known about the emotional patterns of MMA participants during training programs, especially before, during, and after RWL. Although evidence suggested the importance of getting adequate weight loss and mood states for enhancing performance during training moments and championships, there is not yet a study about the relationship between RWL and mood states in MMA athletes. In the present study, we offer hypotheses that propose using RWL strategies will be associated with a negative mood state. We expect to see the largest differences at the weigh-in, a point that should capture extreme weight loss and when the quality of the opponent is known. Therefore, the aim of the present study was to compare 4 moments during body weight modifications (30 days, 1 day, and 10 minutes before the bout and after the bout) in professional MMA fighters.
Experimental Approach to the Problem
Data were collected at 4 points in time: first, 30 days before the competition; second, at the “official weigh-in,” which is held 24 hours before the fight; third, 10 minutes precompetition; and fourth, 10 minutes postcompetition (Figure 1).
The sample comprised 12 professional male MMA athletes (age range = 16–42 years) separated in RWL group (9 fighters [mean ± SD]: 25.6 ± 4.5 years, height = 1.72 ± 0.04 m, body mass = 77.8 ± 7.1 kg) and no rapid weight loss (NWL) group (3 fighters [mean ± SD]: 30.7 ± 13.3 years, height = 1.74 ± 0.09 m, body mass = 80.0 ± 5.2 kg), belonging to the Mato Grosso State in Brazil, during competition period of 2015. All participants had experience in national-level MMA tournament, competing in the last season before the experiment. As performance could influence mood (22), an inclusion criterion was established where each participant had won his previous contest (33), be ranked in the top 30 for his country, and to have less than 1 year of period within the contests. Exclusion criteria included not using athletes who were disqualified, and “no contest” (doping cases). The study received the approval of the ethics committee of the Western Parana State University. After being informed of the risks and benefits, the athletes aged 18 years or older and the parents or guardians of athletes younger than 18 years signed a consent form. Subjects under 18 also provided written informed consent.
Participants were training regularly (technical and tactical) 2 times per day 10 times per week (5 MMA sessions and 5 conditioning and strength training) during the evaluation period. Each MMA session composed of 15 minutes of warm-up, 15 minutes of technical training, and 60 minutes of technical-tactical training or simulated contest, resulting in a combined time totaling 90 minutes of exercise. Conditioning and strength training were composed of 60 minutes of MMA actions, weight training, Olympic lifts, and variations. Strength endurance training was composed by repeated contractions under conditions of fatigue, with more than 15 repetitions with light loading (30–60% of 1 repetition maximum [1RM]). Power training was composed by fast power full MMA movements, which required medium number of sequential actions (6–10 reps) with medium to heavy loading (70–80% of 1RM). Maximum strength sessions with low number of repetitions (1 to 5 reps) with heavy loads (80–100% of 1RM) were realized in less quantity.
Rapid Weight Loss Strategies
A strategic water consumption method was used where fighters manipulate water and sodium levels, maintain a carb intake of lower than 50 g·d−1. They wore warmer clothes during training and, 1 day before to the weigh-in, hot baths and sauna to sweat to lose weight.
This is an exploratory pilot study that used a longitudinal retrospective design. The body mass measured with the use Filizola weighing scales accurate to 0.1 kg. Mood states were assessed using the Brunel Mood Scale (BRUMS) (42,43). The BRUMS has been translated into Portuguese and validated in a Brazilian population by Rohlfs et al. (39). The instrument comprises 24 items rated on a 5-point scale ranging from 0 (not at all) to 4 (extremely). The standard reference time frame used is a “how do you feel right now.”
The BRUMS comprises 6 subscales (tension, depression, anger, vigor, fatigue, and confusion), each consisting of 4 mood descriptors. Each subscale is scored from 0 to 16. Internal consistency values (Cronbach's alpha) for each of the 6 subscales and for the entire combined scale were all greater than 0.76 in the study by Rohlfs et al. (39). In terms of the nature of each mood state (22,41):
- Tension—defined by feeling nervous, anxious, panicky, and worried. It should be noted that this might not be high directly observed musculoskeletal tension.
- Depression—defined by feeling dejected, downhearted, unhappy, and miserable is depressed mood rather than a clinical state of depression.
- Anger—defined as feeling annoyed, angry, bad-tempered, and bitter.
- Vigor factor—defined as feeling active, lively, energetic, and alert.
- Fatigue—defined as feeling sleepy, exhausted, tired, and worn-out.
- Confusion—defined as feeling mixed-up, uncertain, confused, and muddled.
In addition, it is possible to obtain a single measure of mood disturbance by summing scores for negative mood scales and subtracting this score from vigor (total mood disturbance = vigor − [anger + confusion + depression + fatigue + tension]). In the present study, the internal consistency of the total scale was 0.83, while those of the factors were as follows: anger, α = 0.63; confusion, α = 0.63; depression, α = 0.65; fatigue, α = 0.61; tension, α = 0.64; and vigour, α = 0.82. There is some disagreement on the criterion for an acceptable alpha coefficient with alpha coefficients being greater than 0.70 as a commonly reported value. Loewenthal (25) argued an alpha coefficient over 0.60. Lance et al. (24) argue that caution is urged when interpreting cut-off criteria. In the present study, an acceptable criterion was found for the TMD and vigor scale. For the TMD, the alpha coefficient would be enhanced by using more items. It well known that the alpha coefficient is influenced by the number of items (24,41). This observation helps explain why the alpha coefficient for all 24-item TMD was deemed acceptable. All the unpleasant mood factors had lower alphas when analyzed independently but when seen together, as in the case of TMD, the alpha increases. The BRUMS has been the focus of numerous validation studies (42), which show the integrity of the 6-factor scale, studies that used confirmatory factor analysis, a more rigorous technique than using alpha coefficients (41). However, given how important it is to have valid and reliable measures to test theory, we believe low alpha values are a source of concern. We suggest that further work is needed. Recent research examining changes in emotion has used a single item to assess each concept (22), an argument that brevity in some contexts might be preferable over attempts to gain acceptable alpha values. It is noted that the interitem reliability in the current investigation may limit extrapolation of the results.
Data are presented as mean values, SDs, or interquartile range. Before analysis, the normality of all variables was evaluated using Shapiro-Wilk test. Depending on the normality or nonnormality of data distribution, a comparison across the different time was performed by 2-way repeated-measures analysis of variance [(training moment × weigh-in) (RWL × NWL)] with Bonferroni post hoc tests or Friedman test with Mann-Whitney U-test. To allow a better interpretation of the results, the effect sizes (ESs) were calculated (eta squared, η2). Effect sizes for nonparametric analysis were calculated, defined as , where ES represents the effect size, Z is derived from the conversion of Mann-Whitney U-test, and N is the total number of observations. To interpret the resulting eta squared ES, present study classified η2: <0.1 = trivial effect, between ≥0.1 and <0.2 = small effect, between ≥0.2 and <0.5 = moderate effect, and >0.5 = large difference effect (6). The 95% confidence intervals (CIs) were calculated and a significance level of p ≤ 0.05 was used for all analysis. All statistical analyses were carried out using the statistics package for social science (SPSS, Inc., Chicago, IL, USA; version. 20.0).
Mixed martial arts athletes who used RWL strategies reported reduced body mass significantly by 11.6 ± 3.5 kg during 30 days. Participants' mass was 77.8 ± 7.1 kg at the weigh-in 30 days before competition and 66.2 ± 7.2 kg (Figure 2) at the official weigh-in.
A significant interaction effect for changes in bodymass over time between groups (F1,10 = 33.989; p ≤ 0.001; η2 = 0.77) indicated that the RWL group during training moment demonstrated higher body mass value than in official weigh-in (p ≤ 0.001; 95% CI = 8.890; 14.221). However, there was no significant difference observed in NWL group between training and official weigh-in moments (p = 0.42; 95% CI = −2.202; 3.535). The NWL group showed higher body mass value than the RWL group during official weigh-in (p = 0.015; 95% CI = 13.111; 4.453).
In terms of performance, 10 athletes won their fights (83.3%) and the victory by finishing was the most common (n = 7; 58.3%), also winning by technical knockout (n = 2; 16%) and one (8.3%) victory by decision of the arbitration. Among those who lost (n = 2; 16.7%), one was by arbitration decision and another by knockout. There was no significant difference in the mood assessed between the athletes who won and those who lost the match (p > 0.05 for all).
Table 1 showed the descriptive analysis of mood states in MMA fighters throughout different assessment points. In terms of differences in mood, the RWL group reported higher scores for confusion (X2 = 8.081, p = 0.044, df = 3). The RWL group reported higher values than official weigh-in (p = 0.047, ES = 0.16) and before competition (p = 0.016, ES = 0.20). Results for total mood disturbance (X2 = 14.461, p = 0.002, df = 3) indicated that the RWL reported lower values at 30 days before competition, at the official weigh-in (p = 0.008, ES = 0.22), pre-bout (p = 0.008, ES = 0.22), and after competition (p = 0.011, ES = 0.21). No effects were observed in NWL group within comparisons of anger (p = 0.41), confusion (p = 0.19), depression (p = 0.39), fatigue (p = 0.43), tension (p = 0.24), vigor (p = 0.56), and total mood disturbance (p = 0.12). No effects were observed in RWL within comparisons of anger (p = 0.24), depression (p = 0.19), fatigue (p = 0.22), tension (p = 0.15), and vigor (p = 0.25).
At the assessment on 30 days from competition, results show no effects for NWL and RWL in comparisons of anger (p = 0.48), confusion (p = 0.86), depression (p = 0.86), fatigue (p = 0.86), tension (p = 0.48), vigor (p = 0.86), and total mood disturbance (p = 0.48). This trend was consistent for data collection at the official weigh-in (confusion, p = 0.28; depression, p = 1.00; fatigue, p = 0.48; tension, p = 0.37; vigor, p = 0.28; and total mood disturbance, p = 0.21) and before competition (anger, p = 0.60; confusion, p = 0.86; depression, p = 1.00; fatigue, p = 1.00; tension, p = 0.21; vigor, p = 0.86; and total mood disturbance, p = 0.37). Before competition, there were no effects for NWL and RWL comparisons of anger (p = 0.86), confusion (p = 0.48), depression (p = 0.60), fatigue (p = 0.86), tension (p = 0.48), vigor (p = 0.28), and total mood disturbance (p = 0.86).
Regarding the weight of the athletes in training, in the periods of 29 days, 22 days, 15 days, 07 days, official weigh-in, only a difference was observed in the last 2 weeks (week 03 and week 04) before the official weigh-in (Table 2).
Regarding group comparisons, a main effect was verified in anger during official weigh-in (W = 48.000, p = 0.037, df = 3), where NWL group showed higher values than RWL group (p = 0.037, ES = 0.17). No other effects were observed when compared moments or groups (p > 0.05 for all mood measures).
The aim of the present study was to examine changes in bodyweight and mood states among professional MMA fighters, examining fighters who used RWL strategies, comparing data against fighters who did not. This is the first study to examine the effects of RWL in mood states of MMA professional fighters to the authors' knowledge. The intense nature of MMA competition and potential risks of injury coupled with the deleterious health implications associated with engaging in extreme body weight reductions suggest that this is an important area of investigation. Fighters use RWL strategies to gain a physical advantage over an opponent on the basis of an assumption that weight and strength can be regained after weigh-in (15,17,20). In the present study, the control of body weight was evaluated 30 days before the competition. Results are consistent with previous research showing similar amounts of RWL occurs, with ∼7% of total body weight, in short periods of 10–20 days (12) until 4 weeks, with weight loss between ∼16 and ∼5% from total body weight (3,37).
In terms of performance, it seems that there were no significant differences and therefore engaging in RWL did not seem to harm nor help performance. Athletes had a large difference ES in the reduction in body weight after 30 days of weight loss period, from the first data collection to the competition. It should be noted that the present study did not pair opponents and therefore we do not know if one fighter rapidly lost weight and the other fighter did not. If both fighters engage in severe weight loss strategies, it could affect performance via the mechanisms outlined previously but because there has to be a winner, it might be a false assumption that RWL had no effect on performance. It should be noted that some studies did not report significant changes of performance after usage of RWL strategies (2,13,26,28). It has been suggested that a reduction of ∼5% in first body mass does not present significant changes in performance, provided that the athlete has a few hours to feed and hydrate after weighing (3).
In terms of changes in mood, results show RWL associated with feeling more confused 30 days from competition than fighters who did not intend to use rapid weight-making strategies. Although the result was significant, and ES was moderate, this result hints at the possibility that engaging in RWL creates a sense of uncertainty. Furthermore, the RWL group also reported greater total mood disturbance at all assessment points with a moderate difference ES, an affective profile associated with poor adaptation to training in previous research (18,22).
Although previous research has found that changes in athletes' mood states relates to performance in competition (7,8), our data do not point to a relationship between these aspects. The hypothesis that RWL can lead to emotional changes was not supported in the present study. We suggest that throughout the athletic career, the athlete accumulates experience, and these changes of weight, suggest both physical and emotional adaptations, make the athlete achieve a good emotional regulation even with a water deficit and nutritional deficit.
Sport psychologists should reflect supporting for athletes' rights and responsible practices to avoid dangerous methods of RWL through procedures that could put athletes' mental and physical health at risk. Preceding reports showed a high percentage of inappropriate methods of weight loss (10,27). An epidemiological study demonstrated that 60% of combat athletes reported using a method of RWL through increased energy expenditure and ∼50% of them use saunas, diuretics, and plastic clothing, and only 26.1% received advice from a nutritionist (27). Based on the assumption that dangerous methods can alter mood states and put athlete's life at risk, the present study controlled this type of intervention during data collection.
Choma et al. (9) found that mood changes, as a function of body weight decrease, are not maintained after the athlete returns to normal weight. Thus, even though there is a decrease in weight, some changes in mood, after nutrient intake, the mood returns to optimal levels. The present study looked at correlations between amounts of weight loss and mood states in MMA fighters; results reveal important contributions; however, because we looked at fighters who are adapted to RWL (37), these findings may not translate to other sports.
The results show RWL leads to mood disturbance (5). It is not known if this in turn affects performance. Our results can be combined with recent findings in the same field and can be used to make the following suggestions:
- Rapid weight loss could have substantial risks to health and performance; therefore, athletes should be discouraged to reduce weight by any means, leading to dehydration and starvation. Increasing the usual amount of exercise and adjusting diet in long-term seem to be the most appropriate procedures when performed throughout the competitive season (28).
- When considering the psychological aspects related to weight reduction, athletes consider acute weight loss as a mentally important part of the precompetitive preparation (23,26).
- The individuals who are the most influential in teaching athlete's strategies for weight loss are typically the coach, training partners, or former athletes; educational programs should focus on providing them with full explanations of how to properly advise MMA fighters about weight management procedures (14).
- Global MMA weigh-in regulations should be addressed with immediate effect to ensure the mental health of competitors (19).
Future research should investigate the influence of weight loss and mood states (7,8), together with environmental factors related to athletes' expectations (16), technical-tactical actions (30), and mental skills (40). Associated to mood states analysis, this psychological assessment of athletes will give the opportunity to identify how an athlete cope with stress induced by weight loss and by a competition and various mental preparation strategies should be advised for performance enhancement (7).
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