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1.
Int J Sport Nutr Exerc Metab ; 34(5): 275-285, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38871343

RESUMO

Mixed martial arts' popularity has increased in recent years, alongside descriptive research and evidence-based performance recommendations. Guidelines for (both chronic and acute) weight making exist; however, how these translate in real-life scenarios and detailed investigations on practices in larger groups deserve attention. The present study examined the body mass (BM) and composition of 33 professional mixed martial arts athletes preparing for 80 fights. Athletes were supported by on-site dietitians, who encouraged evidence-based practices. Fasted BM was measured throughout the last ∼10 days before all bouts (acute weight management phase). A subset of athletes had body composition assessed before and after the chronic weight loss phase for 40 fights. Most athletes engaged in chronic BM loss, and all engaged in acute weight loss. Many lost fat-free mass (FFM) during the chronic phase, with rates of BM loss <0.5% best preserving FFM. Regardless of losses, the present athletes possessed greater FFM than other combat sport athletes and engaged in greater acute weight loss. Dehydration in the 24-48 hr before the weigh-in was not reflective of weight regain after the weigh-in, rather BM 7-10 days before the weigh-in was most reflective. These findings suggest that many mixed martial arts athletes could increase FFM at the time of competition by maintaining leaner physiques outside of competition and/or allowing increased time to reduce BM chronically. Acutely, athletes can utilize evidence-based protocols, eliminating carbohydrates, fiber, sodium, and finally fluid in a staged approach, before the weigh-in, reducing the amount of sweating required, thus theoretically better protecting health and preserving performance.


Assuntos
Atletas , Composição Corporal , Artes Marciais , Redução de Peso , Humanos , Artes Marciais/fisiologia , Masculino , Adulto , Adulto Jovem , Desidratação/prevenção & controle , Feminino , Peso Corporal
2.
Nutrients ; 16(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38613083

RESUMO

The aim of this systematic review is to comprehensively assess the weight loss (WL) practices in different combat sports (CS). The review protocol was preregistered with PROSPERO [CRD42023487196]. Three databases were searched (Web of Science, EBSCOhost, and PubMed) until 8 December 2023. Eligible studies had to meet five criteria: they must have been (a) written in English, (b) published in a peer-reviewed journal, (c) used a survey design to investigate the WL practices of CS athletes, and (d) reported the WL methods used by athletes using a five-point scale. Twenty-six studies (3994 participants from 14 CS) were included. This review found that (1) WL is highly prevalent in CS athletes; (2) many CS athletes started losing weight for competition as teenagers two to three times a year; (3) CS athletes usually lose <5% body weight in 7-14 days before competition; (4) increasing exercise and gradually dieting are the most commonly used WL methods; and (5) the influence of scientific practitioners on athletes is negligible. The habitual practices of CS athletes may be relatively harmless, but in some special cases, CS athletes also perform extreme WL practices. Scientific practitioners have little influence on their WL practices, which may form a vicious cycle of non-qualified influence.


Assuntos
Atletas , Redução de Peso , Humanos , Artes Marciais/fisiologia , Masculino , Feminino , Adolescente , Exercício Físico , Luta Romana/fisiologia , Dieta Redutora , Adulto , Adulto Jovem , Boxe , Esportes
3.
Nutr Health ; : 2601060231201892, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697737

RESUMO

Background: Rapid weight loss (RWL) practices are common amongst strength-sport athletes to 'make weight' for a chosen weight class. Aim: This study compared the RWL practices of International Powerlifting Federation (IPF) powerlifters from Great Britain. Methods: Participants (n = 69, male = 36, female = 33) were recruited from IPF lifting populations (mandatory <2-hour competition weigh-in). Participants were categorised based on highest level of competition (regional, national and international) and also sex (male and female). The previously validated 'Rapid Weight Loss Questionnaire' established RWL practices, however also included an open-ended question regarding thoughts, feeling and mood during RWL. Results: Nearly all participants (97%) had purposely acutely reduced body mass to compete, with an average typical pre-competition loss of 4.2%. Regional competitors reported a higher 'typical' body mass loss compared to international competitors (5.5% vs 3.3%, p = 0.004). Females reported a greater 'highest' body mass loss than males (6.7% vs 5.3%, p = 0.028). Fluid restriction (86.5%), water loading (67.2%) and increased exercise (49.2%) were the RWL methods most commonly used 'always' or 'sometimes'. Content analysis revealed a predominance of negative perceptions during RWL with the emergence of codes; fatigue, sensations, anxiety, low mood and irritation, accounting for ∼70% of responses. Conclusion: Prevalence of RWL is high amongst competitive powerlifters, with many competitors attributing negative perceptions during the weight-cutting process. The magnitude of reported acute RWL within regional lifters was beyond where performance decrements are commonly seen (>5%), this should be cautioned against given the IPF's mandatory <2-hour competition weigh-in.

4.
J Funct Morphol Kinesiol ; 7(4)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36547661

RESUMO

Previous research has demonstrated that professional mixed martial arts (MMA) athletes employ a variety of weight manipulation strategies to compete at given weight classes. Although there is much literature demonstrating weight manipulation methods, minimal research exists analyzing how much weight MMA athletes lose prior to the official weigh-in. Moreover, there is minimal research examining how much weight professional MMA athletes gain between the official weigh-in and competition. Therefore, the purpose of the current study was to analyze weight loss/regain in professional MMA athletes. Data collected from 616 professional MMA athletes (31.1 ± 4.0 yrs.; 177.1 ± 4.7 cm) competing for the Ultimate Fighting Championship (UFC) between 2020 and 2022 were used for the study. The athlete's weight was obtained 72 h, 48 h, and 24 h prior to the official weigh-in, at the official weigh-in, and prior to competition. Random effects analysis was utilized to compare weight at a variety of time points between different weight classes. All statistics were analyzed, and significance was set at p ≤ 0.05. There is a significant (p ≤ 0.05) difference between weight classes and time points in professional MMA. MMA athletes decrease body weight significantly prior to the official weigh-in. MMA athletes increase body weight significantly between official weigh-in and competition. Based on these data, it appears that MMA athletes average a weight loss of nearly 7% within 72 h prior to the official weigh-in. The data also suggest that athletes gain nearly 10% of total weight between the official weigh-in and competition.

5.
J Int Soc Sports Nutr ; 19(1): 380-396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35859622

RESUMO

Background: Rapid weight loss (RWL) followed by rapid weight gain (RWG) is a regular pre-competition routine in combat sports and weightlifting. With the prevalence of these sports exceeding 20% at the 2020 Tokyo Olympics, there are limited data on RWL and RWG practices and their impact on well-being and competitive success in elite-level athletes. Methods: A total of 138 elite-level female and male judokas, 7.7% of the athletes ranked as top 150 on the International Judo Federation Senior World Ranking List (WRL), completed a survey on RWL, RWG, and the consequences of these practices. Results: Our findings showed that 96% of the respondents practice RWL. The average reduced body mass percentage was 5.8 ± 2.3%. Respondents who used either of the dehydration methods - fluid restriction, sauna suit, and/or sauna/hot bath - to reduce weight were 88%, 85%, and 76%, respectively. Furthermore, 91% of the respondents reported reduced energy as a negative consequence of RWL and 21% experienced a collapse episode during the RWL period. Respondents ranked 1-20 on the WRL experienced fewer negative consequences of RWL and RWG (p = 0.002) and had more dietitian and/or medical doctor support (p = 0.040) than lower-ranked respondents. Those who started with RWL practices before the age of 16 (38%) were ranked lower on the WRL (p = 0.004) and reported more negative consequences of RWL and RWG (p = 0.014). Conclusions: This study is the first to provide insight into the RWL practices of worldwide elite-level judokas and provides valuable information for the combat sports society, especially coaches. Proper weight management and optimal timed initiation of RWL practices in a judoka's career may contribute to success at the elite level.


Assuntos
Artes Marciais , Redução de Peso , Atletas , Feminino , Humanos , Masculino , Estado Nutricional , Aumento de Peso
6.
Medicina (Kaunas) ; 57(6)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072641

RESUMO

Even though scientific literature shows numerous heath complications and performance decrements associated with rapid weight loss (RWL), its prevalence remains exceedingly high across various combat sports. The aim of this study was to thoroughly search the existing literature to explore the influence of RWL on kidney function in Olympic and non-Olympic combat sport athletes. PubMed and Web of Science were searched for the relevant studies. Only original articles published from 2005 onwards, written in English, that included healthy males and females who prompted ~5% weight loss within a week or less, were included in the study. Retrieved studies showed that creatinine, blood urea nitrogen and urine specific gravity values were significantly increased after RWL in the majority of the included studies. This observation indicates that RWL caused dehydration and subsequent acute kidney damage despite various degrees of weight lost during the RWL phase, which can lead to adverse events in other body systems. Alternative methods of weight reduction that prioritize athletes' health should be considered.


Assuntos
Artes Marciais , Redução de Peso , Atletas , Peso Corporal , Feminino , Humanos , Rim , Masculino
7.
Int J Exerc Sci ; 14(6): 324-337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055173

RESUMO

Compromised bone density in jockeys has previously been identified as an important health and safety concern in horseracing. Despite this, no update on the bone density status in Irish jockeys has been provided in the past decade. The study aimed to conduct a comprehensive update of the current bone density status in professional Irish jockeys and identify possible contributory physical and lifestyle factors. Eighty-five professional male jockeys (flat n = 39; national hunt (NH) n = 46) completed a dual-energy X-ray absorptiometry (DXA) scan for the assessment of body composition and bone mineral density (BMD) at the lumbar spine (LS), femoral neck (FN) and hip, 24-hour food recall, bone-specific physical activity questionnaire (BPAQ) and lifestyle questionnaire on weight making practices and injury history. Z-scores were interpreted to assess current bone density status. Correlation analysis was used to identify physical and lifestyle factors associated with bone mineral apparent density (BMAD). Results revealed a high prevalence of low BMD (Z-score < - 1.0) at the LS (44%), FN (15%) and hip (29%) in Irish jockeys. Analysis of jockeys physical characteristics found a positive relationship with the LS but not FN BMAD. Riding experience and timing of weight cut in NH and the practice of cutting weight in flat jockeys negatively influenced BMAD sites, while supplement use in flat jockeys displayed a positive effect on LS BMAD. Findings indicate the need for targeted individualised support strategies. Further investigation is required into jockey-specific intervention strategies that promote the development of optimal bone health in professional jockeys.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33255390

RESUMO

It is common practice in combat sports that athletes rapidly lose body weight before a match, by applying different practices-some safer and others possibly dangerous. The factors behind the choice of practices utilised have not been fully studied. This study aimed to investigate the weight loss strategies used by Italian boxers and to look at the difference between higher and lower risk practice adaptors. A modified version of a validated questionnaire has been sent to 164 amateur (88%) and professional (12%) boxers by email. A heatmap with hierarchical clustering was used to explore the presence of subgroups. Weight loss strategies were used by 88% of the athletes. Two clusters were found, defined by the severity of weight loss behaviours. Professional fighters, high-level athletes and females were more represented in Cluster 2, the one with more severe weight-loss practices. These athletes were characterised by a higher weight loss magnitude and frequency throughout the season and reported being more influenced by physicians and nutritionists, compared with the boxers in Cluster 1. Not all the weight loss practices are used with the same frequency by all boxers. The level of the athlete and the boxing style have an influence on the weight-cutting practices.


Assuntos
Boxe , Análise por Conglomerados , Redução de Peso , Adolescente , Adulto , Peso Corporal/fisiologia , Boxe/estatística & dados numéricos , Feminino , Humanos , Itália , Masculino , Inquéritos e Questionários , Adulto Jovem
9.
Int J Sport Nutr Exerc Metab ; 30(5): 357-361, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663387

RESUMO

Body mass (BM) manipulation via rapid weight loss (RWL) and rapid weight gain (RWG) is a common practice among mixed martial art (MMA) athletes to ensure qualification for the division in which the athlete wishes to compete. Professional MMA competitors in California are required to weigh in twice: 24 hr prior to competition and immediately prior to the bout after they have typically engaged in RWG. In analyzing data from five MMA events sanctioned by the Californian State Athletic Commission, the authors used Bayesian analyses to compare bout winners (n = 62) and losers (n = 62) in terms of in-competition BM (in kilograms) and the amount of BM regained between the two weigh-ins (in kilograms). These data do not support the hypothesis that differences in in-competition BM (Bayes factor [BF10] = 0.667, d = 0.23) or the amount of BM regained between the two weigh-ins (BF10 = 0.821, d = 0.23) determine winning or losing. In addition, there was no statistical difference between bouts ending via strikes, submission, or decision for either in-competition BM (BF10 = 0.686, ω2 < 0.01) or the amount of BM regained between the two weigh-ins (BF10 = 0.732, ω2 = 0.054). In conclusion, the authors report for the first time that the magnitude of RWG does not predict winning or losing in a professional cohort of MMA athletes. In addition, they also report that MMA athletes typically compete at a BM that is at least 1-2 divisions higher than the division in which they officially weighed-in. These analyses may provide impetus for governing bodies and coaches to enact changes at both professional and amateur levels to reduce negative health consequences associated with extreme RWL and RWG.


Assuntos
Atletas , Peso Corporal , Artes Marciais , Aumento de Peso , Teorema de Bayes , California , Comportamento Competitivo , Humanos , Fenômenos Fisiológicos da Nutrição Esportiva
10.
Nutrients ; 12(5)2020 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357500

RESUMO

Rapid weight loss (RWL) is commonly practiced among judo athletes. Although it helps them to gain the advantage over their lighter opponents, previous studies have shown that RWL can have a negative impact on the athlete's performance and overall well-being. This systematic review aimed to synthesize the evidence that examines the influence of rapid weight loss on physiological parameters, biomarkers, and psychological well-being in judo athletes. We followed the preferred reporting items for systematic reviews and meta-analyses guidelines. We searched for studies on Web of Science and PubMed that elaborate on the influence of ≥5% RWL achieved over ≤7-day period in judokas. Out of 52 studies initially found, 14 studies met our eligibility criteria and were included in the review. In total, we examined data from 1103 judo athletes. Retrieved studies showed conflicting data concerning physiological parameters and biomarkers, while psychological well-being parameters were more consistent than physiological and biomarkers. The feeling of tension, anger, and fatigue significantly increased while a decrease in vigor was demonstrated among athletes who lost weight rapidly. The evidence on the impact of RWL on performance remains ambiguous. More studies under standardized conditions are needed in order to provide firm evidence. Considering the harmful effects of RWL outlined in the existing literature, it is important to determine and monitor athlete's minimal competitive weight to prioritize the health and safety of the athlete, emphasize fairness, and ultimately benefit the sport.


Assuntos
Atletas/psicologia , Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Artes Marciais/fisiologia , Artes Marciais/psicologia , Redução de Peso , Programas de Redução de Peso/métodos , Adulto , Ira , Fadiga , Humanos , Masculino , Estresse Psicológico , Fatores de Tempo , Adulto Jovem
11.
Int J Sports Physiol Perform ; 15(2): 213-221, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31094260

RESUMO

PURPOSE: To examine the influence of fluid intake on heat acclimation and the subsequent effects on exercise performance following acute hypohydration. METHODS: Participants were randomly assigned to 1 of 2 groups, either able to consume water ad libitum (n = 10; age 23 [3] y, height 1.81 [0.09] m, body mass 87 [13] kg; HAW) or not allowed fluid (n = 10; age 26 [5] y, height 1.76 [0.05] m, body mass 79 [10] kg; HANW) throughout 12 × 1.5-h passive heat-acclimation sessions. Experimental trials were completed on 2 occasions before (2 baseline trials) and 1 following the heat-acclimation sessions. These sessions involved 3 h of passive heating (45°C, 38% relative humidity) to induce hypohydration followed by 3 h of ad libitum food and fluid intake after which participants performed a repeat sled-push test to assess physical performance. Urine and blood samples were collected before, immediately, and 3 h following hypohydration to assess hydration status. Mood was also assessed at the same time points. RESULTS: No meaningful differences in physiological or performance variables were observed between HANW and HAW at any time point. Using pooled data, mean sprint speed was significantly (P < .001) faster following heat acclimation (4.6 [0.7] s compared with 5.1 [0.8] s). Furthermore, heat acclimation appeared to improve mood following hypohydration. CONCLUSIONS: Results suggest that passive heat-acclimation protocols may be effective at improving short-duration repeat-effort performance following acute hypohydration.


Assuntos
Aclimatação , Desempenho Atlético/fisiologia , Desidratação/fisiopatologia , Ingestão de Líquidos/fisiologia , Temperatura Alta , Redução de Peso , Afeto , Desempenho Atlético/psicologia , Pressão Sanguínea , Cognição , Frequência Cardíaca , Humanos , Masculino , Análise e Desempenho de Tarefas
12.
Sports (Basel) ; 7(5)2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117325

RESUMO

In combat sports, athletes are divided into categories based on gender and body mass. Athletes attempt to compete against a lighter opponent by losing body mass prior to being weighed (i.e., 'weight-cutting'). The purpose of this narrative review was to explore the current body of literature on weight-cutting and outline gaps for further research. Methods of weight-loss include energy intake restriction, total body fluid reduction and pseudo extreme/abusive medical practice (e.g., diuretics). The influence of weight-cutting on performance is unclear, with studies suggesting a negative or no effect. However, larger weight-cuts (~5% of body mass in <24 h) do impair repeat-effort performance. It is unclear if the benefit from competing against a smaller opponent outweighs the observed reduction in physical capacity. Many mechanisms have been proposed for the observed reductions in performance, ranging from reduced glycogen availability to increased perceptions of fatigue. Athletes undertaking weight-cutting may be able to utilise strategies around glycogen, total body water and electrolyte replenishment to prepare for competition. Despite substantial discussion on managing weight-cutting in combat sports, no clear solution has been offered. Given the prevalence of weight-cutting, it is important to develop a deeper understanding of such practices so appropriate advice can be given.

13.
Int J Sport Nutr Exerc Metab ; 29(4): 441­452, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299200

RESUMO

Combat sport athletes typically engage in a process called making weight, characterized by rapid weight loss (RWL) and subsequent rapid weight gain (RWG) in the days preceding competition. These practices differ across each sport, but no systematic comparison of the size of the changes in body mass exists. The aim was to determine the magnitude of RWL and RWG in combat sport athletes preparing for competition. The review protocol was preregistered with PROSPERO (CRD42017055279). In eligible studies, athletes prepared habitually with a RWL period ≤7 days preceding competition. An electronic search of EBSCOhost (CINAHL Plus, MEDLINE, and SPORTDiscus) and PubMed Central was performed up to July 2018. Sixteen full-text studies (total 4,432 participants; 156 females and 4,276 males) were included, providing data from five combat sports (boxing, judo, mixed martial arts, taekwondo, and wrestling). Three studies reported RWL and 14 studies reported RWG. Duration permitted for RWG ranged 3-32 hr. The largest changes in body mass occurred in two separate mixed martial arts cohorts (RWL: 7.4 ± 1.1 kg [∼10%] and RWG: 7.4 ± 2.8 kg [11.7% ± 4.7%]). The magnitude of RWG appears to be influenced by the type of sport, competition structure, and recovery duration permitted. A cause for concern is the lack of objective data quantifying the magnitude of RWL. There is insufficient evidence to substantiate the use of RWG as a proxy for RWL, and little data are available in females. By engaging in RWG, athletes are able to exploit the rules to compete up to three weight categories higher than at the official weigh-in.


Assuntos
Atletas , Comportamento Competitivo , Aumento de Peso , Redução de Peso , Peso Corporal , Boxe , Feminino , Humanos , Masculino , Artes Marciais , Luta Romana
14.
Int J Sport Nutr Exerc Metab ; 29(3): 331-338, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29989458

RESUMO

The aim of the present case study was to quantify the physiological and metabolic impact of extreme weight cutting by an elite male mixed martial arts athlete. Throughout an 8-week period, we obtained regular assessments of body composition, resting metabolic rate, peak oxygen uptake, and blood clinical chemistry to assess endocrine status, lipid profiles, hydration, and kidney function. The athlete adhered to a "phased" weight loss plan consisting of 7 weeks of reduced energy (ranging from 1,300 to 1,900 kcal/day) intake (Phase 1), 5 days of water loading with 8 L/day for 4 days followed by 250 ml on Day 5 (Phase 2), 20 hr of fasting and dehydration (Phase 3), and 32 hr of rehydration and refueling prior to competition (Phase 4). Body mass declined by 18.1% (80.2 to 65.7 kg) corresponding to changes of 4.4, 2.8, and 7.3 kg in Phases 1, 2, and 3, respectively. We observed clear indices of relative energy deficiency, as evidenced by reduced resting metabolic rate (-331 kcal), inability to complete performance tests, alterations to endocrine hormones (testosterone: <3 nmol/L), and hypercholesterolemia (>6 mmol/L). Moreover, severe dehydration (reducing body mass by 9.3%) in the final 24 hr prior to weigh-in-induced hypernatremia (plasma sodium: 148 mmol/L) and acute kidney injury (serum creatinine: 177 µmol/L). These data, therefore, support publicized reports of the harmful (and potentially fatal) effects of extreme weight cutting in mixed martial arts athletes and represent a call for action to governing bodies to safeguard the welfare of mixed martial arts athletes.


Assuntos
Injúria Renal Aguda/etiologia , Desidratação/etiologia , Dieta Redutora/efeitos adversos , Artes Marciais , Redução de Peso , Atletas , Metabolismo Basal , Composição Corporal , Peso Corporal , Creatinina/sangue , Jejum , Humanos , Hipernatremia/etiologia , Masculino , Adulto Jovem
15.
Front Physiol ; 9: 1562, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30450056

RESUMO

Introduction/Purpose: This study examined the influence of acute dehydration on neuromuscular function. Methods: On separate days, combat sports athletes experienced in acute dehydration practices (n = 14) completed a 3 h passive heating intervention (40°C, 63% relative humidity) to induce dehydration (DHY) or a thermoneutral euhydration control (25°C, 50% relative humidity: CON). In the ensuing 3 h ad libitum fluid and food intake was allowed, after which participants performed fatiguing exercise consisting of repeated unilateral knee extensions at 85% of their maximal voluntary isometric contraction (MVIC) torque until task failure. Both before and after the fatiguing protocol participants performed six MVICs during which measures of central and peripheral neuromuscular function were made. Urine and whole blood samples to assess urine specific gravity, urine osmolality, haematocrit and serum osmolality were collected before, immediately and 3 h after intervention. Results: Body mass was reduced by 3.2 ± 1.1% immediately after DHY (P < 0.001) but recovered by 3 h. Urine and whole blood markers indicated dehydration immediately after DHY, although blood markers were not different to CON at 3 h. Participants completed 28% fewer knee extensions at 85% MVIC (P < 0.001, g = 0.775) and reported a greater perception of fatigue (P = 0.012) 3 h after DHY than CON despite peak torque results being unaffected. No between-condition differences were observed in central or peripheral indicators of neuromuscular function at any timepoint. Conclusion: Results indicate that acute dehydration of 3.2% body mass followed by 3 h of recovery impairs muscular strength-endurance and increases fatigue perception without changes in markers of central or peripheral function. These findings suggest that altered fatigue perception underpins muscular performance decrements in recovery from acute dehydration.

16.
Eur J Sport Sci ; 18(7): 920-929, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29746803

RESUMO

Urine specific gravity (USG) is the most commonly reported biochemical marker used in research and applied settings to detect fluid deficits in athletes, including those participating in combat sports. Despite the popularity of its use, there has been a growing debate regarding the diagnostic accuracy and the applicability of USG in characterizing whole-body fluid status and fluctuations. Moreover, recent investigations report universally high prevalence of hypohydration (∼90%) via USG assessment in combat sport athletes, often in spite of stable body-mass. Given the widespread use in both research and practice, and its use in a regulatory sense as a 'hydration test' in combat sports as a means to detect dehydration at the time of weigh-in; understanding the limitations and applicability of USG assessment is of paramount importance. Inconsistencies in findings of USG readings, possibly as a consequence of diverse methodological research approaches and/or overlooked confounding factors, preclude a conclusive position stand within current combat sports research and practice. Thus the primary aim of this paper is to critically review the literature regarding USG assessment of hydration status in combat sports research and practice. When taken on balance, the existing literature suggests: the use of laboratory derived benchmarks in applied settings, inconsistent sampling methodologies, the incomplete picture of how various confounding factors affect end-point readings, and the still poorly understood potential of renal adaptation to dehydration in combat athletes; make the utility of hydration assessment via USG measurement quite problematic, particularly when diet and training is not controlled.


Assuntos
Boxe , Desidratação/diagnóstico , Desidratação/urina , Luta Romana , Atletas , Comportamento Competitivo , Ingestão de Líquidos , Humanos , Gravidade Específica , Urinálise
17.
Int J Sport Nutr Exerc Metab ; 28(6): 565-573, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29182412

RESUMO

Novel methods of acute weight loss practiced by combat sport athletes include "water loading," the consumption of large fluid volumes for several days prior to restriction. We examined claims that this technique increases total body water losses, while also assessing the risk of hyponatremia. Male athletes were separated into control (n = 10) and water loading (n = 11) groups and fed a standardized energy-matched diet for 6 days. Days 1-3 fluid intake was 40 and 100 ml/kg for control and water loading groups, respectively, with both groups consuming 15 ml/kg on Day 4 and following the same rehydration protocol on Days 5 and 6. We tracked body mass (BM), urine sodium, urine specific gravity and volume, training-related sweat losses and blood concentrations of renal hormones, and urea and electrolytes throughout. Physical performance was assessed preintervention and postintervention. Following fluid restriction, there were substantial differences between groups in the ratio of fluid input/output (39%, p < .01, effect size = 1.2) and BM loss (0.6% BM, p = .02, effect size = 0.82). Changes in urine specific gravity, urea and electrolytes, and renal hormones occurred over time (p < .05), with an interaction of time and intervention on blood sodium, potassium, chloride, urea, creatinine, urine specific gravity, and vasopressin (p < .05). Measurements of urea and electrolyte remained within reference ranges, and no differences in physical performance were detected over time or between groups. Water loading appears to be a safe and effective method of acute BM loss under the conditions of this study. Vasopressin-regulated changes in aquaporin channels may potentially partially explain the mechanism of increased body water loss with water loading.


Assuntos
Água Corporal , Ingestão de Líquidos , Redução de Peso , Adulto , Atletas , Análise Química do Sangue , Composição Corporal , Peso Corporal , Dieta , Eletrólitos , Hidratação , Humanos , Masculino , Artes Marciais , Urinálise , Vasopressinas , Água , Luta Romana , Adulto Jovem
18.
Int J Sports Physiol Perform ; 13(7): 933-939, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29283792

RESUMO

CONTEXT: Combat sports are typically divided into weight classes, and body-mass manipulation to reach a weight class is commonplace. Previous research suggests that weight loss practices in mixed martial arts (MMA) may be more extreme than in other combat sports. PURPOSE: To investigate the magnitude of weight loss and the prevalence of weight loss strategies in different combat sports. METHODS: Competitors (N = 637) from Brazilian jiu-jitsu, boxing, judo, MMA, Muay Thai/kickboxing, taekwondo, and wrestling completed an online questionnaire seeking information regarding their weight loss practices. RESULTS: Body-mass manipulation was commonly undertaken by all combat-sport athletes, with a particularly high incidence of gradual dieting, increased exercise, and fluid restriction. Skipping meals was higher in taekwondo and wrestling (84%) compared with the other combat sports (∼58%), whereas training in heated rooms and forced oral fluid loss (spitting) was higher in wrestling (83% and 47%, respectively) compared with other combat sports (∼45% and ∼19%, respectively). MMA athletes reported the highest usage of sauna (76%) and water loading (67%) while also reporting the second-highest use of training in rubber/plastic suits (63%). CONCLUSIONS: Body-mass manipulation was present in all combat sports, with the prevalence and magnitude of acute weight loss greater in MMA. The incidence of and practices reported will help support staff be fully aware of the variety of methods these athletes and coaches may use to achieve weight loss. Additionally, the results could aid regulatory bodies in the further development of policies on weight cutting.


Assuntos
Boxe/fisiologia , Comportamento Competitivo/fisiologia , Artes Marciais/fisiologia , Redução de Peso , Luta Romana/fisiologia , Adulto , Índice de Massa Corporal , Boxe/classificação , Desidratação/etiologia , Feminino , Hábitos , Humanos , Masculino , Artes Marciais/classificação , Luta Romana/classificação , Adulto Jovem
19.
Int J Sports Physiol Perform ; 12(2): 142-151, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27347784

RESUMO

It is common for athletes in weight-category sports to try to gain a theoretical advantage by competing in weight divisions that are lower than their day-to-day body mass (BM). Weight loss is achieved not only through chronic strategies (body-fat losses) but also through acute manipulations before weigh-in ("making weight"). Both have performance implications. This review focuses on Olympic combat sports, noting that the varied nature of regulations surrounding the weigh-in procedures, weight requirements, and recovery opportunities in these sports provide opportunity for a wider discussion of factors that can be applied to other weight-category sports. The authors summarize previous literature that has examined the performance effects of weightmaking practices before investigating the physiological nature of these BM losses. Practical recommendations in the form of a decision tree are provided to guide the achievement of acute BM loss while minimizing performance decrements.


Assuntos
Boxe/fisiologia , Comportamento Competitivo/fisiologia , Artes Marciais/fisiologia , Redução de Peso/fisiologia , Luta Romana/fisiologia , Água Corporal/fisiologia , Árvores de Decisões , Dieta , Ingestão de Alimentos , Humanos
20.
Int J Sports Physiol Perform ; 12(7): 856-863, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27834565

RESUMO

PURPOSE: Combat-sport athletes acutely reduce body mass (BM) before weigh-in in an attempt to gain a size/strength advantage over smaller opponents. Few studies have investigated these practices among boxers and none have explored the impact of this practice on competitive success. METHODS: One hundred (30 women, 70 men) elite boxers participating in the Australian national championships were weighed at the official weigh-in and 1 h before each competition bout. Regain in BM after weigh-in was compared between finalists and nonfinalists, winners and losers of each fight, men and women, and weight divisions. Boxers were surveyed on their pre- and post-weigh-in nutrition practices. RESULTS: The lightest men's weight category displayed significantly greater relative BM regain than all other divisions, with no difference between other divisions. BM prebout was higher than official weigh-in for men (2.12% ± 1.62%; P < .001; ES = 0.13) and women (1.49% ± 1.65%; P < .001; ES = 0.11). No differences in BM regain were found between finalists and nonfinalists, winners and losers of individual bouts, or between preliminary or final bouts. BM regain was significantly greater (0.37% BM, P < .001; ES = 0.25) before an afternoon bout compared with a morning bout. CONCLUSIONS: Boxers engage in acute BM-loss practices before the official competition weigh-in, but this does not appear to affect competition outcomes, at least when weight regain between weigh-in and fighting is used as a proxy for the magnitude of acute loss. While boxers recognize the importance of recovering after weigh-in, current practice is not aligned with best-practice guidance.


Assuntos
Atletas , Desempenho Atlético , Peso Corporal , Boxe , Aumento de Peso , Comportamento Competitivo , Feminino , Humanos , Masculino , Redução de Peso
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