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1.
Int J Sport Nutr Exerc Metab ; : 1-9, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39467540

RESUMO

This study explored the body mass (BM) management practices among competitive male and female Olympic weightlifting athletes, hypothesizing that athletes compete in lighter weight categories than their habitual training weight (i.e., making weight). Utilizing a validated, anonymous survey, data were collected from 149 Olympic weightlifting athletes (>18 years; female = 94). The survey comprised five sections: demographics, training/competition history, weight history, source of influence, and BM management practices. The prevalence, magnitude, and methods employed for BM management were analyzed with subgroup analysis using one-way analysis of variance. Post hoc testing including Spearman's rho and chi-square analysis was completed when a significant effect was found. Three quarters (76%) of athletes acknowledged using chronic weight loss and/or acute weight loss strategies to make weight. Usual BM loss (2%-3%) in the week before competition was within recommended guidelines. Gradual dieting, fluid restriction, and low food weight, high-calorie options were the most commonly used BM management strategies. Female athletes were more likely to use gradual dieting (p = .043; r = .104) and were less likely to increase their exercise (p = .046; r = -.105) and utilize fasting (p = .038; r = .05) compared with their male counterparts. Women further identified dietitians/nutritionists (p = .006; r = .022) as a highly influential source of information. This research offers new insights into the BM management practices of Olympic weightlifting athletes, identifying that the majority of athletes compete at a BM lighter than their habitual training weight, achieved using a range of chronic weight loss and acute weight loss strategies.

2.
J Strength Cond Res ; 38(9): 1627-1634, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38985931

RESUMO

ABSTRACT: Dunican, IC, Galpin, A, Turner, M, and Reale, R. Sleep behaviors and nutritional knowledge in amateur and professional combat sport athletes. J Strength Cond Res 38(9): 1627-1634, 2024-Combat sports is a term applied to various competitive contact sports involving 2 competitors engaging in a bout or contest under a specific ruleset. Little is known about combat sports athletes' sleep and nutritional knowledge. This study aimed to assess (a) sleep behaviors, (b) alcohol and shiftwork disorders, and (c) the nutritional knowledge of combat sports athletes. Subjects completed various demographic questions and estimations of their weight management practices and validated surveys, including the Athlete Sleep Behavior Questionnaire, Shiftwork Disorder (SWD) Screening Questionnaire, Alcohol Use Disorders Identification Test, and the Abridged Nutrition for Sports Knowledge Questionnaire. A total of 844 combat sports athletes completed the survey, 79% male, height of 177 ± 10 (cm), and body mass of 79 ± 15 (kg). Subjects were categorized into their specific combat sport type (e.g., boxing or Brazilian jiu-jitsu [BJJ]) and by their level (professional or amateur). Sleep quality was average for all combat sport types and risk prevalence of shiftwork disorder at 11%. Mann-Whitney U tests revealed that amateurs, compared with professional strikers ( p = 0.046, CLES = 0.80), boxers ( p = 0.01, CLES = 0.78), and BJJ ( p = 0.046, CLES = 0.61) athletes, consumed significantly more alcohol. A Friedman test showed significant ( p < 0.001, W = 0.51) differences in weight between time points, with most combat sports athletes reducing weight for competition. An overall nutritional knowledge average of 55% was reported. This study highlights a critical gap in the knowledge and practices of combat sports athletes in relation to sleep behaviors and disorders, alcohol consumption, and nutritional knowledge, emphasizing the need for targeted educational interventions.


Assuntos
Atletas , Conhecimentos, Atitudes e Prática em Saúde , Sono , Humanos , Masculino , Feminino , Sono/fisiologia , Atletas/estatística & dados numéricos , Adulto Jovem , Adulto , Inquéritos e Questionários , Boxe/fisiologia , Artes Marciais/fisiologia , Adolescente , Jornada de Trabalho em Turnos
3.
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
4.
Int J Sports Physiol Perform ; 18(1): 85-94, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473482

RESUMO

PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.


Assuntos
Boxe , Artes Marciais , Humanos , Masculino , Estudos Retrospectivos , Aumento de Peso , Artes Marciais/fisiologia , Atletas
6.
Phys Sportsmed ; 50(6): 494-500, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34310264

RESUMO

OBJECTIVES: Weight classifications are used in boxing and other combat sports to match opponents of similar size. Professional boxers commonly engage in a potentially harmful practice known as rapid weight loss or 'weight cutting' to make weight the day prior to competition before rehydrating and refueling. This investigation describes the prevalence and magnitude of rapid weight gain in boxers following weigh-in as well as differences in practice with respect to weight class and promotion. METHODS: This analysis describes official weight data from male professional boxers collected by the California State Athletic Commission between 2015 and 2018. A total of 399 athletes were included in the study. RESULTS: Among included athletes, 389 (97.5%) athletes gained weight between official weigh-in and competition. Total absolute body mass gained was 4.4 ± 2.2 kg corresponding to a total relative body mass gain of 7.2 ± 3.5%. Boxers competing in international promotions gained significantly more body mass than regional competitors (8.0 ± 3.0% vs. 6.6 ± 3.7%; p < 0.001). In total, 82 (20.6%) athletes gained 10% body mass or more before competition. More international competitors reached this 10% threshold than regional competitors (25.3% vs. 17.4%; p = 0.03). CONCLUSIONS: These findings indicate high prevalence and magnitude of RWG in professional boxing, particularly in boxers competing in elite international promotions.


Assuntos
Boxe , Artes Marciais , Humanos , Masculino , Peso Corporal , Comportamento Competitivo , Redução de Peso , Aumento de Peso , Atletas
7.
Eur J Sport Sci ; 22(5): 720-732, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34043489

RESUMO

Weight making can be described as the process of reducing body mass in events where aesthetics, propulsion or the requirement to meet a specific weight category limit, are considered to be of competitive importance. Cross sectional research specifically focussed on weight category sports, has highlighted behaviours and practices that are similar in athletes of both sexes. Regardless of this and despite parallel participation in weight category sporting events, females are drastically underrepresented in studies examining body mass loss interventions across both chronic and acute timeframes. However, it has been well characterised that these types of body mass loss strategies can be causative of low energy availability, leading to consequences of female athlete triad and relative energy deficiency in sports. Furthermore, female-specific body composition and physiological systems modulated by the anterior pituitary and ovarian hormones within the menstrual cycle or use of hormonal contraception, can lead to potential outcomes which need to be considered carefully, particularly when employing acute weight loss strategies that are often utilised by weight making athletes. Therefore, the aim of this article serves to review the aforementioned issues, whilst offering practical recommendations via initial assessment, chronic/acute interventions and refeeding/recovery plans to help support the implementation of body mass loss strategies in the context of weight making specifically with female athletes.


Assuntos
Síndrome da Tríade da Mulher Atleta , Esportes , Atletas , Composição Corporal , Estudos Transversais , Feminino , Humanos
8.
Artigo em Inglês | MEDLINE | ID: mdl-34639501

RESUMO

Studies have shown that nitrate (NO3-)-rich beetroot juice (BJ) supplementation improves endurance and high-intensity intermittent exercise. The dose-response effects on taekwondo following BJ supplementation are yet to be determined. This study aimed to investigate two acute doses of 400 mg of NO3- (BJ-400) and 800 mg of NO3- (BJ-800) on taekwondo-specific performance and cognitive function tests compared with a placebo (PL) and control (CON) conditions. Eight trained male taekwondo athletes (age: 20 ± 4 years, height: 180 ± 2 cm, body mass: 64.8 ± 4.0 kg) completed four experimental trials using a randomized, double-blind placebo-controlled design: BJ-400, BJ-800, PL, and CON. Participants consumed two doses of BJ-400 and BJ-800 or nitrate-depleted PL at 2.5 h prior to performing the Multiple Frequency Speed of Kick Test (FSKT). Countermovement jump (CMJ) was performed before the (FSKT) and PSTT, whereas cognitive function was assessed (via the Stroop test) before and after supplementation and 10 min following PSTT. Blood lactate was collected before the CMJ tests immediately and 3 min after the FSKT and PSST; rating of perceived exertion (RPE) was recorded during and after both specific taekwondo tests. No significant differences (p > 0.05), with moderate and large effect sizes, between conditions were observed for PSTT and FSKT performances. In addition, blood lactate, RPE, heart rate, and CMJ height were not significantly different among conditions (p > 0.05). However, after the PSTT test, cognitive function was higher in BJ-400 compared to other treatments (p < 0.05). It was concluded that acute intake of 400 and 800 mg of NO3- rich BJ reported a moderate to large effect size in anaerobic and aerobic; however, no statistical differences were found in taekwondo-specific performance.


Assuntos
Desempenho Atlético , Beta vulgaris , Adolescente , Adulto , Anaerobiose , Atletas , Cognição , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Sucos de Frutas e Vegetais , Humanos , Nitratos , Projetos Piloto , Adulto Jovem
9.
J Int Soc Sports Nutr ; 18(1): 40, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34044858

RESUMO

BACKGROUND: Carbohydrate (CHO) ingestion enhances exercise performance; however, the efficacy of CHO intake on repeated bouts of exercise simulating a taekwondo tournament is unknown. Therefore, the purpose was to compare the effects of two different doses of CHO on a sports-specific kicking test during a simulated taekwondo tournament compared to placebo (PLA). METHODS: In a double-blind, randomized-placebo controlled, cross-over trial, eleven junior male professional taekwondo athletes (age: 16 ± 0.8 years, body mass: 55.3 ± 7.3 kg) ingested one of three solutions: (i) high dose (C45): 45 g of CHO (60 g∙h- 1), (ii) low dose (C22.5): 22.5 g of CHO (30 g∙h- 1; both solutions containing 2:1 glucose:fructose), or a PLA immediately following each kicking test. The kicking test was repeated 5 times, separated by 45 mins of rest, simulating a typical taekwondo competition day. Ratings of perceived exertion (RPE) and gastrointestinal discomfort (GI) scores were collected immediately after, and blood glucose before each test. RESULTS: The results revealed that C45 and C22.5 did not improve total, successful, or percentage of successful kicks compared to PLA (p > 0.05). Blood glucose was significantly higher following both CHO conditions compared with PLA across all five tests (p < 0.05). There were no differences between treatments or across tests for RPE (p > 0.05). CONCLUSION: CHO intake, independent of the dose, did not alter taekwondo kick performance during a simulated taekwondo tournament.


Assuntos
Desempenho Atlético/fisiologia , Sacarose Alimentar/administração & dosagem , Frutose/administração & dosagem , Artes Marciais/fisiologia , Adolescente , Bebidas , Glicemia/metabolismo , Índice de Massa Corporal , Comportamento Competitivo/fisiologia , Estudos Cross-Over , Sacarose Alimentar/efeitos adversos , Método Duplo-Cego , Frutose/efeitos adversos , Azia/etiologia , Humanos , Masculino , Percepção/fisiologia , Esforço Físico/fisiologia
10.
Sleep Sci ; 13(1): 18-24, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670488

RESUMO

It is well documented that many adolescents are not meeting current sleep duration recommendations, with a growing body of literature suggesting adolescent athletes also fall into this category. What is less known is the relationship between current and ideal sleep behaviors. We sought to quantify sleep behaviors in a group of athletes and to understand how their current behaviors compare to their self-reported ideal behaviors. One hundred ninety six competitive, male and female athletes (15.7 ± 1.3 y) completed the Pittsburgh Sleep Quality Index (PSQI) and a questionnaire that captured usual sleep habits. The PSQI was analyzed for habitual bedtime, wake time, sleep duration, and sleep quality. The usual sleep habits questionnaire was analyzed for ideal bedtime, wake time, and calculated sleep duration. Reported mean sleep duration was 7:45 ± 1:06 h:min. Actual bedtime was later (+0:44 ± 0:05 h:min, p<0.001) than ideal bedtime, actual wake time was earlier (-0:50 ± 0:08 h:min, p<0.001) than ideal wake time, and actual sleep duration was less (-2:11 ± 1:27 h:min, p<0.001) than ideal sleep duration. Adolescent athletes are not meeting current sleep duration recommendations and there are significant discrepancies between self-reported current and ideal sleep behaviors in this group.

11.
Int J Sport Nutr Exerc Metab ; 30(4): 249-257, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460240

RESUMO

We sought to assess the accuracy of current or developing new prediction equations for resting metabolic rate (RMR) in adolescent athletes. RMR was assessed via indirect calorimetry, alongside known predictors (body composition via dual-energy X-ray absorptiometry, height, age, and sex) and hypothesized predictors (race and maturation status assessed via years to peak height velocity), in a diverse cohort of adolescent athletes (n = 126, 77% male, body mass = 72.8 ± 16.6 kg, height = 176.2 ± 10.5 cm, age = 16.5 ± 1.4 years). Predictive equations were produced and cross-validated using repeated k-fold cross-validation by stepwise multiple linear regression (10 folds, 100 repeats). Performance of the developed equations was compared with several published equations. Seven of the eight published equations examined performed poorly, underestimating RMR in >75% to >90% of cases. Root mean square error of the six equations ranged from 176 to 373, mean absolute error ranged from 115 to 373 kcal, and mean absolute error SD ranged from 103 to 185 kcal. Only the Schofield equation performed reasonably well, underestimating RMR in 51% of cases. A one- and two-compartment model were developed, both r2 of .83, root mean square error of 147, and mean absolute error of 114 ± 26 and 117 ± 25 kcal for the one- and two-compartment model, respectively. Based on the models' performance, as well as visual inspection of residual plots, the following model predicts RMR in adolescent athletes with better precision than previous models; RMR = 11.1 × body mass (kg) + 8.4 × height (cm) - (340 male or 537 female).


Assuntos
Atletas , Metabolismo Basal , Absorciometria de Fóton , Adolescente , Composição Corporal , Calorimetria Indireta , Feminino , Humanos , Masculino , Modelos Teóricos
12.
Eur J Sport Sci ; 20(2): 147-156, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31092119

RESUMO

Physique traits of a range of elite athletes have been identified; however, few detailed investigations of Olympic combat sports (judo, wrestling, taekwondo and boxing) exist. This is surprising given the importance of body composition in weight category sports. We sought to develop a descriptive database of Olympic combat sport athletes, compare variables relative to weight division and examine differences within and between sports. Additionally, we investigated the appropriateness of athletes' self-selected weight classes compared to an internationally recognised classification system (the NCAA minimum wrestling weight scheme used to identify minimum 'safe' weight). Olympic combat sport athletes (56♂, 38♀) had body mass (BM), stretch stature and dual-energy X-ray absorptiometry derived body composition assessed within 7-21 days of competition. Most athletes were heavier than their weight division. Sport had an effect (p < .05) on several physique traits, including; lean mass, lean mass distribution, stretch stature and BMI. BM was strongly positively correlated (r > 0.6) with; fat free mass, fat mass and body fat percentage, however, was not predictive of total mass/weight division. The Olympic combat sports differ in competitive format and physiological requirements, which is partly reflected in athletes' physique traits. We provide reference ranges for lean and fat mass across a range of BM. Lighter athletes likely must utilise acute weight loss in order to make weight, whereas heavier athletes can potentially reduce fat mass.


Assuntos
Atletas , Composição Corporal , Boxe/fisiologia , Artes Marciais/fisiologia , Redução de Peso , Luta Romana/fisiologia , Absorciometria de Fóton , Estudos Transversais , Feminino , Humanos , Masculino
13.
Eur J Nutr ; 58(2): 497-514, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30820653

RESUMO

PURPOSE: Athletes in Olympic combat sports experience body water fluctuations resulting from training and intentional dehydration when making weight. Despite the popularity of urine specific gravity (USG) and urine osmolality (UOSM) measurement in characterizing fluid fluctuations, their utility remains questioned. This systematic review/meta-analysis examined the utility of urinary hydration indices in laboratory and field settings in Olympic combat sport athletes. METHODS: 27 articles met the inclusion criteria for systematic review, 15 studies were included in the meta-analysis; with USG and UOSM the main outcome variables. Meta-regression analyses evaluated the interrelationship among body mass (BM), fluid intake, and urine measures. RESULTS: Significant USG alterations were observed following different sampling time frames: dehydration (ES 0.59; 95% CI 0.46-0.72; p = 0.001), follow-up period (ES 0.31; 95% CI 0.11-0.50; p = 0.002) and rehydration (ES - 0.34; 95% CI - 0.56 to - 0.12; p = 0.003). Direct comparison of laboratory (ES 0.20; 95% CI - 0.19 to 0.59; p = 0.324) and field (ES 0.35; 95% CI 0.14-0.56; p = 0.001) sampling showed marginally trivial and small effects. Small effects on UOSM were observed following dehydration (ES 0.31; 95% CI 0.12-0.74, p = 0.15), follow-up period (ES 0.39; 95% CI 0.08-0.70, p = 0.015) and rehydration (ES - 0.45; 95% CI - 0.60 to 0.30, p = 0.001). Meta-regression analysis suggests only fluid intake predicts USG alterations (p = 0.044) during rehydration protocols. CONCLUSIONS: There were likely small changes in both USG and UOSM readings across all experimental conditions, with moderate-to-large heterogeneity in all studies, except for USG readings during dehydration protocols. The meta-regression failed to provide conclusive evidence concerning the interrelationship among urine measures, BM fluctuations, and fluid intake.


Assuntos
Atletas/estatística & dados numéricos , Desidratação/epidemiologia , Desidratação/fisiopatologia , Ingestão de Líquidos/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Desidratação/urina , Feminino , Humanos , Masculino , Concentração Osmolar , Esportes , Urinálise , Adulto Jovem
14.
J Sports Sci ; 37(7): 762-771, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30319077

RESUMO

The aim of this study was to perform a systematic review and meta-analysis on the acute and chronic effects of sodium bicarbonate (NaHCO3) ingestion on Wingate performance. Following a search through PubMed, Scopus and Web of Science, 9 studies were found meeting inclusion criteria (6 acute and 3 chronic). Random-effects meta-analysis of standardized mean difference (SMD) for peak and mean power was performed. Study quality was assessed using the QualSyst. Results of the meta-analysis showed that acute ingestion of NaHCO3 did not improve Wingate test peak (weighted average effect size Hedges's g = 0.02, 95%CI: - 0.19 to 0.23, P = 0.87) or mean power (weighted average effect size Hedges's g = 0.15, 95%CI: -0.06 to 0.36, P = 0.92). However, chronic ingestion of NaHCO3 improved Wingate test peak (weighted average effect size Hedges's g = 1.21, 95%CI: 0.83 to 1.42, P = 0.001) and mean power (weighted average effect size Hedges's g = 1.26, 95%CI: 0.96 to 1.56, P = 0.001). Quality assessment of selected articles was classified as strong. This meta-analysis provides evidence that chronic, but not acute, ingestion of NaHCO3 increases both Wingate test peak and mean power.


Assuntos
Acidose/prevenção & controle , Desempenho Atlético/fisiologia , Teste de Esforço/métodos , Bicarbonato de Sódio/administração & dosagem , Administração Oral , Esquema de Medicação , Metabolismo Energético/efeitos dos fármacos , Humanos , Fadiga Muscular/fisiologia , Bicarbonato de Sódio/sangue
15.
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
16.
Int J Sports Physiol Perform ; 13(4): 459-466, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28872383

RESUMO

PURPOSE: Combat sport athletes undertake chronic and rapid weight loss (RWL) practices to qualify for weight divisions lower than their training weight. Variation between sports in the prevalence, methods, and magnitude of weight loss as well as recovery practices may be influenced by factors including competition level and culture. Differences in methodologies of previous research in combat sports make direct comparisons difficult; thus, this study aimed to examine weight loss practices among all Olympic combat sports in Australia, using standardized methodology. METHODS: High-caliber competitors in wrestling, boxing, judo, and taekwondo (n = 260) at Australian competitions were surveyed using a validated tool that provides quantification of how extreme an athlete's weight loss practices are: the rapid weight loss score (RWLS). Additional qualitative and quantitative survey data were also collected. RESULTS: Neither sport, sex, nor weight division group had an effect on RWLS; however, a significant effect of athlete caliber was detected (F2,215 = 4.953, mean square error = 4.757, P = .00792). Differences between sports were also evident for most weight ever lost in order to compete (H = 19.92, P = .0002), age at which weight cutting began (H = 16.34, P = .001), and selected methods/patterns of RWL (P < .001). Weight cycling between competitions was common among all sports as were influences on athlete's behaviors. CONCLUSIONS: Although many similarities in weight loss practices and experiences exist between combat sports, specific differences were evident. Nuanced, context/culturally specific guidelines should be devised to assist fighters' in optimizing performance while minimizing health implications.


Assuntos
Boxe/fisiologia , Comportamento Competitivo/fisiologia , Artes Marciais/fisiologia , Redução de Peso , Luta Romana/fisiologia , Adulto , Austrália , Índice de Massa Corporal , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
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.
Eur J Sport Sci ; 17(6): 727-740, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28316263

RESUMO

Olympic combat sports separate athletes into weight divisions, in an attempt to reduce size, strength, range and/or leverage disparities between competitors. Official weigh-ins are conducted anywhere from 3 and up to 24 h prior to competition ensuring athletes meet weight requirements (i.e. have 'made weight'). Fighters commonly aim to compete in weight divisions lower than their day-to-day weight, achieved via chronic and acute manipulations of body mass (BM). Although these manipulations may impair health and absolute performance, their strategic use can improve competitive success. Key considerations are the acute manipulations around weigh-in, which differ in importance, magnitude and methods depending on the requirements of the individual combat sport and the weigh-in regulations. In particular, the time available for recovery following weigh-in/before competition will determine what degree of acute BM loss can be implemented and reversed. Increased exercise and restricted food and fluid intake are undertaken to decrease body water and gut contents reducing BM. When taken to the extreme, severe weight-making practices can be hazardous, and efforts have been made to reduce their prevalence. Indeed some have called for the abolition of these practices altogether. In lieu of adequate strategies to achieve this, and the pragmatic recognition of the likely continuation of these practices as long as regulations allow, this review summarises guidelines for athletes and coaches for manipulating BM and optimising post weigh-in recovery, to achieve better health and performance outcomes across the different Olympic combat sports.


Assuntos
Peso Corporal , Boxe/fisiologia , Dieta , Artes Marciais/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva , Redução de Peso , Atletas , Humanos
19.
J Strength Cond Res ; 31(10): 2832-2839, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28081034

RESUMO

This study examined the effects of evening use of electronic devices (i.e., smartphones, etc.) on sleep quality and next-day athletic and cognitive performance in elite judo athletes. Over 6 consecutive days and nights, 23 elite Australian judo athletes were monitored while attending a camp at the Australian Institute of Sport (AIS). In 14 athletes, all electronic devices were removed on days 3 and 4 (i.e., for 48 hours: the "device-restricted group"), whereas 9 were permitted to use their devices throughout the camp (the "control group"). All athletes wore an activity monitor (Readiband) continuously to provide measures of sleep quantity and quality. Other self-reported (diary) measures included time in bed, electronic device use, and rate of perceived exertion during training periods. Cognitive performance (Cogstate) and physical performance (single leg triple hop test) were also measured. When considering night 2 as a "baseline" for each group, removal of electronic devices on nights 3 and 4 (device-restricted group) resulted in no significant differences in any sleep-related measure between the groups. When comparing actigraphy-based measures of sleep to subjective measures, all athletes significantly overestimated sleep duration by 58 ± 85 minutes (p = 0.001) per night and underestimated time of sleep onset by 37 ± 72 minutes (p = 0.001) per night. No differences in physical or cognitive function were observed between the groups. CONCLUSION: This study has shown that the removal of electronic devices for a period of two nights (48 hours) during a judo camp does not affect sleep quality or quantity or influence athletic or cognitive performance.


Assuntos
Atletas , Computadores de Mão , Artes Marciais/fisiologia , Sono/fisiologia , Actigrafia , Adolescente , Desempenho Atlético , Austrália , Cognição , Humanos , Masculino , Percepção , Adulto Jovem
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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