Nutritional Ergogenic Aids in Combat Sports: A Systematic Review and Meta-Analysis.

Nutritional ergogenic aids (NEAs) are substances included within the group of sports supplements. Although they are widely consumed by athletes, evidence-based analysis is required to support training outcomes or competitive performance in specific disciplines. Combat sports have a predominant use of anaerobic metabolism as a source of energy, reaching peak exertion or sustained effort for very short periods of time. In this context, the use of certain NEAs could help athletes to improve their performance in those specific combat skills (i.e., the number of attacks, throws and hits; jump height; and grip strength, among others) as well as in general physical aspects (time to exhaustion [TTE], power, fatigue perception, heart rate, use of anaerobic metabolism, etc.). Medline/PubMed, Scopus and EBSCO were searched from their inception to May 2022 for randomised controlled trials (RCTs). Out of 677 articles found, 55 met the predefined inclusion criteria. Among all the studied NEAs, caffeine (5-10 mg/kg) showed strong evidence for its use in combat sports to enhance the use of glycolytic pathways for energy production during high-intensity actions due to a greater production of and tolerance to blood lactate levels. In this regard, abilities including the number of attacks, reaction time, handgrip strength, power and TTE, among others, were improved. Buffering supplements such as sodium bicarbonate, sodium citrate and beta-alanine may have a promising role in high and intermittent exertion during combat, but more studies are needed in grappling combat sports to confirm their efficacy during sustained isometric exertion. Other NEAs, including creatine, beetroot juice or glycerol, need further investigation to strengthen the evidence for performance enhancement in combat sports. Caffeine is the only NEA that has shown strong evidence for performance enhancement in combat sports.

Weight Loss Strategies in Male Competitors of Combat Sport Disciplines.

Background and objective: The use of suboptimal weight loss strategies in order to reach specific weight ranges as observed in combat sport disciplines can give rise to severe health problems. However, particular aspects regarding management of weight category comparing three sport disciplines remain to be investigated. Therefore, the aim of the present study was to obtain information regarding the weight loss strategies that competitors performed before a tournament. Materials and Methods: This article describes the most common dietary-nutritional strategies used by 140 national university male competitors of judo (n = 52), karate (n = 40) and taekwondo (n = 48) in order to achieve a specific weight, according to the rapid weight loss questionnaire (RWLQ) and the EAT-27 questionnaire. Results: Around 50% of participants were not involved in a weight loss process. Among the remaining participants, we considered three periods for weight reduction: less than 1 week (35% in judo, 8% in karate and 19% in taekwondo), less than 1 month (17% in judo, 15% in karate and 26% in taekwondo) and more than 1 month (0% in judo, 5% in karate and 21% in taekwondo). Severe fasting, focused on food/water restriction, was the most commonly used strategy, being more frequent in judo players. Light weight judo practitioners generally lost 2-5 kg before the contest. One third of participants avoided carbohydrate consumption when performing food restriction. Finally, individuals that reduced weight in the last week seemed to develop an unhealthy psychological relationship with food. Conclusion: All these aspects could be particularly relevant, providing information regarding how competitors manage basic nutritional concepts that guide dieting strategies. This information is relevant to prepare future educational interventions in the area of nutrition for competitors, coaches and technical staff.

Nutritional Ergogenic Aids in Racquet Sports: A Systematic Review.

A nutritional ergogenic aid (NEA) can help athletes optimize performance, but an evidence-based analysis is required in order to support training outcomes or competition performance in specific events. Racquet sports players are regularly exposed to a high-intensity workload throughout the tournament season. The activity during a match is characterized by variable durations (2-4 h) of repeated high-intensity bouts interspersed with standardized rest periods. Medline/PubMed, Scopus, and EBSCO were searched from their inception until February 2020 for randomized controlled trials (RCTs). Two independent reviewers extracted data, after which they assessed the risk of bias and the quality of trials. Out of 439 articles found, 21 met the predefined criteria: tennis (15 trials), badminton (three trials), paddle (one trial), and squash (two trials). Among all the studied NEAs, acute dosages of caffeine (3-6 mg/kg) 30-60 min before a match have been proven to improve specific skills and accuracy but may not contribute to improve perceived exertion. Currently, creatine, sodium bicarbonate, sodium citrate, beetroot juice, citrulline, and glycerol need more studies to strengthen the evidence regarding improved performance in racquet sports.

EATING DISORDERS AND DIET MANAGEMENT IN CONTACT SPORTS; EAT-26 QUESTIONNAIRE DOES NOT SEEM APPROPRIATE TO EVALUATE EATING DISORDERS IN SPORTS.

INTRODUCTION: there is a growing concern in the appearance of eating disorders in athletes, especially those that practice sports grouped into weight categories. This affects the way athletes eat, using frequently unhealthy strategies to control weight, especially during the pre-competition period. AIM: this study analyses the prevalence of contact sports athletes in developing eating disorders, and how a controlled diet plan can reduce this risk. At the same time, it evaluates the use of the EAT-26 questionnaire to detect such disorders. METHODS: a randomized frequency study was performed on 244 athletes (158 men, 86 women), who were separated into two groups: those that followed a diet plan given by a nutritionist, and a control group on a free diet. The athletes completed an EAT-26 questionnaire while participating in the University-level National Championships. RESULTS: the free diet group scored significantly higher on the questionnaire. Also, the female athletes controlled diet group scored significantly higher than their male counterparts. DISCUSSION: the results of the questionnaire indicate that an adequate nutritional program circumvents the use of unhealthy habits to control body weight and therefore avoids developing particular eating disorders. EAT-26 questionnaire does not seem the most appropriate tool to detect these disorders.

Introducción: existe una preocupación creciente por los desórdenes alimentarios en deportistas, especialmente en aquellos que practican deportes agrupados en categorías de peso. Esto afecta a la manera de comer de los deportistas, usando con frecuencia estrategias no saludables para control del peso, en especial en periodo precompetitivo. Objetivo: este estudio analiza la prevalencia de desórdenes alimentarios en deportistas de deportes de contacto, y cómo una planificación dietética controlada puede reducir el riesgo. También valora el uso del cuestionario EAT-26 para detectar dichos desórdenes. Métodos: ha sido realizado un estudio aleatorizado de frecuencias en 244 deportistas (158 varones, 86 mujeres), que fueron separados en dos grupos: los que seguían un plan dietético proporcionado por un nutricionista y un grupo control con una dieta libre. Los participantes rellenaron el cuestionario EAT-26 mientras participaban en los Campeonatos Universitarios Nacionales. Resultados: el grupo con dieta libre puntuó con valores más altos en el cuestionario. Al mismo tiempo, las deportistas que seguían una dieta controlada puntuaron de forma significativa en el cuestionario respecto a los varones del mismo grupo. Discusión: los resultados del cuestionario indican que una adecuada planificación nutricional evita el uso de hábitos poco saludables para controlar el peso corporal, evitando desarrollar desórdenes alimentarios particulares. El cuestionario EAT-26 no parece la herramienta más apropiada para detectar estos desórdenes.

Effect of polyphenol supplements on redox status of blood cells: a randomized controlled exercise training trial.

PURPOSE: The effect of endogenous antioxidants can be either an immediate response (relying on enzymatic activities) or a long-term adaptation (relying on gene modulation events), both susceptible to be modified by antioxidants from diet and supplementation. The aim of this work was to delve in these aspects in circulating white blood cells in a group of volunteers (n = 33, 20-22 years) performing eccentric exercises and consuming or not (n = 8) different polyphenolic antioxidants (Lippia citriodora extract-PLX(®) n = 8, almond beverage n = 9 or a mixture of both n = 8) during 21 days. METHODS: We have designed a single-blind, parallel-group, randomized controlled trial. Antioxidant enzyme activities, oxidative stress markers, and antioxidant gene expression were determined. RESULTS: Neutrophils and lymphocytes expressed high amounts of oxidative markers compared to plasma. Concerning enzymatic activities, increased superoxide dismutase levels were detected when certain supplements were consumed. However, catalase levels did not change. As for glutathione peroxidase levels, no differences were detected in lymphocytes, while neutrophils expressed increased levels in both placebo and PLX(®) groups. Glutathione reductase activity was decreased in all groups, except in neutrophils of PLX(®) group. At the level of gene expression, neither PLX(®) nor the almond beverage interfered with the expression of genes coding for the corresponding enzymes. However, the combined intake of both supplements affected the expression of glutathione reductase and Cu-Zn and Mn-superoxide dismutases in neutrophils. CONCLUSIONS: Altogether, these results suggest that blood cell types respond and adapt differently to exercise-induced oxidative damage.