Avaliação da composição corporal e consumo de macronutrientes de mulheres atletas do judô

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da suplementação de taurina ou flavonóides de cacau associado à achocolatado sobre a composição corporal, metabolismo de carboidratos e proteinas, desempenho fisico, dano muscular e estresse oxidativo em atletas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da suplementação de taurina ou flavonóides de cacau associado à achocolatado sobre a composição corporal, metabolismo de carboidratos e proteinas, desempenho fisico, dano muscular e estresse oxidativo em atletas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Methods of body-mass reduction by combat sport athletes

The aim of this study was to investigate the methods adopted to reduce body mass (BM) in competitive athletes from the grappling (judo, jujitsu) and striking (karate and tae kwon do) combat sports in the state of Minas Gerais, Brazil. An exploratory methodology was employed through descriptive research, using a standardized questionnaire with objective questions self-administered to 580 athletes (25.0 +/- 3.7 yr, 74.5 +/- 9.7 kg, and 16.4% +/- 5.1% body fat). Regardless of the sport, 60% of the athletes reported using a method of rapid weight loss (RWL) through increased energy expenditure. Strikers tend to begin reducing BM during adolescence. Furthermore, 50% of the sample used saunas and plastic clothing, and only 26.1% received advice from a nutritionist. The authors conclude that a high percentage of athletes uses RWL methods. In addition, a high percentage of athletes uses unapproved or prohibited methods such as diuretics, saunas, and plastic clothing. The age at which combat sport athletes reduce BM for the first time is also worrying, especially among strikers.

Effects of acute creatine supplementation on iron homeostasis and uric acid-based antioxidant capacity of plasma after wingate test

Background: Dietary creatine has been largely used as an ergogenic aid to improve strength and athletic performance, especially in short-term and high energy-demanding anaerobic exercise. Recent findings have also suggested a possible antioxidant role for creatine in muscle tissues during exercise. Here we evaluate the effects of a 1-week regimen of 20 g/day creatine supplementation on the plasma antioxidant capacity, free and heme iron content, and uric acid and lipid peroxidation levels of young subjects (23.1 +/- 5.8 years old) immediately before and 5 and 60 min after the exhaustive Wingate test. Results: Maximum anaerobic power was improved by acute creatine supplementation (10.5 %), but it was accompanied by a 2.4-fold increase in pro-oxidant free iron ions in the plasma. However, potential iron-driven oxidative insult was adequately counterbalanced by proportional increases in antioxidant ferric-reducing activity in plasma (FRAP), leading to unaltered lipid peroxidation levels. Interestingly, the FRAP index, found to be highly dependent on uric acid levels in the placebo group, also had an additional contribution from other circulating metabolites in creatine-fed subjects. Conclusions: Our data suggest that acute creatine supplementation improved the anaerobic performance of athletes and limited short-term oxidative insults, since creatine-induced iron overload was efficiently circumvented by acquired FRAP capacity attributed to: overproduction of uric acid in energy-depleted muscles (as an end-product of purine metabolism and a powerful iron chelating agent) and inherent antioxidant activity of creatine.

Myostatin: genetic variants, therapy and gene doping

Since its discovery, myostatin (MSTN) has been at the forefront of muscle therapy research because intrinsic mutations or inhibition of this protein, by either pharmacological or genetic means, result in muscle hypertrophy and hyperplasia. In addition to muscle growth, MSTN inhibition potentially disturbs connective tissue, leads to strength modulation, facilitates myoblast transplantation, promotes tissue regeneration, induces adipose tissue thermogenesis and increases muscle oxidative phenotype. It is also known that current advances in gene therapy have an impact on sports because of the illicit use of such methods. However, the adverse effects of these methods, their impact on athletic performance in humans and the means of detecting gene doping are as yet unknown. The aim of the present review is to discuss biosynthesis, genetic variants, pharmacological/genetic manipulation, doping and athletic performance in relation to the MSTN pathway. As will be concluded from the manuscript, MSTN emerges as a promising molecule for combating muscle wasting diseases and for triggering wide-ranging discussion in view of its possible use in gene doping.

La autoconfianza y el control del estrés en futbolistas: revisión de estudios

[ES] El análisis de las variables psicológicas posibilita comprender la relación existente entre el rendimiento deportivo y el deportista. En este estudio se incide sobre las variables autoconfianza y control del estrés en el futbolista. El objetivo es profundizar en los principales estudios científicos realizados en dichas variables. Se utiliza la revisión de fuentes primarias y secundarias como artículos, tesis doctorales y libros. El método utilizado es el análisis y revisión de la literatura.

Análisis de las caracterísicas psicológicas y la toma de decisiones en un grupo de nadadores

[ES] La presente investigación tiene el objetivo de analizar las características psicológicas relacionadas con el rendimiento deportivo y el estilo de toma de decisiones de 70 nadadores, relacionándolos en función del sexo, nivel deportivo y categoría deportiva. Utilizando el cuestionario Características Psicológicas relacionadas con el Rendimiento Deportivo (CPRD) (Gimeno, 1999) y el Cuestionario de Estilo de Toma Decisiones (CETD) (Ruiz, Graupera, y Sánchez, 2000).

Programa de entrenamiento en control de la activación, rendimiento y autoeficacia en golfistas infantiles: un estudio de caso

[ES] Esta investigación tuvo como objetivo comprobar mediante un estudio de caso el efecto de un programa de entrenamiento en control de activación mediante técnicas de respiración y biorretroinformación, sobre la autoeficacia y la efectividad del golpe del putt en cuatro golfistas entre 11 y 14 años.

Exercise capacity in athletes with mouthguards

The objective of this study was to determine the effect of wearing a mouthguard on maximal exercise capacity and cardiopulmonary parameters at peak workload, and to assess the athletes' attitudes toward wearing a mouthguard. Thirteen volunteer male athletes (18 to 27 years old) were interviewed before and after delivery of a custom-made laminated mouthguard. A visual analogue scale (VAS, 0 - 100 mm) was used for judgment of interference with breathing, speaking, concentration and athletic performance. In addition, the athletes were subjected to a cardiorespiratory examination on a cycle ergometer with and without mouthguards. Subjectively, the athletes rated the mean interference with performance to be 37 mm VAS at the beginning of the study. Mean scores of impairment decreased to 23 mm VAS (p = 0.081) after wearing the mouthguard for four weeks, and further improved to 12 mm VAS (p < 0.001) after the test on the cycle ergometer. Objectively, the maximum workload during spiroergometry was even slightly elevated during exercise with the mouthguard (330.2 W) compared to exercise without the mouthguard (314.5 W). Peak minute ventilation and oxygen uptake were not different during exercise with and without the mouthguard. The present study demonstrated that a custom-made mouthguard does not significantly affect or reduce maximum exercise performance of athletes.

Effect of exercise on the mobilization of retinol and retinyl esters in plasma of sled dogs

Fasting dogs do transport vitamin A (VA) in plasma not only as retinol but predominantly as retinyl esters. Contrary to retinol, nothing is known concerning the effects of athletic performance on plasma retinyl ester concentrations. The aim of this study was therefore to examine whether physical stress because of exercise and modification of the oxidative stress by supplementation of alpha-tocopherol influences the concentrations of retinol and retinyl esters in plasma of sled dogs. The study was carried out on 41 trained adult sled dogs, which were randomly assigned into two groups. One group (19 dogs) was daily substituted with 50 mg dl-alpha-tocopheryl acetate per kilogram body weight and the control group (22 dogs) was maintained on a basal diet during 3 months prior to exercise. The plasma concentrations of retinol, retinyl esters, alpha-tocopherol and triglycerides were measured immediately before, directly after and 24 h after exercise. The supplementation of alpha-tocopheryl acetate had no effect on plasma retinol and retinyl ester concentrations at any measurement time point. However, retinyl ester levels doubled in the non-supplemented group immediately after the race (p < 0.001), whereas in the supplemented group similar high levels were observed not until 24 h post-racing (p < 0.001). The high levels of retinyl esters were paralleled to some extent by an increase in plasma triglyceride concentrations, which were significantly higher 24 h post-racing than immediately before (p < 0.001) and after exercise (p < 0.001) in both groups. The increase in retinyl ester concentrations might be indicative of their mobilization from liver and adipose tissue. Whether plasma retinyl esters can be used as an indicator for the extent of nutrient mobilization during and post-exercise in sled dogs remains to be elucidated.

Holistic patterns as an instrument to predict promising young football players

Multidimensional talent models represent the current state of the art. However, it remains unclear how these different dimensions interact. Based on current theories of human development, person-oriented approaches seem to be particularly appropriate for talent research. The present study adopts this approach by looking at how a holistic system consisting of the dimensions motivation, motor behaviour and the stage of development goes along with athletic performance. For this purpose, it has to be examined which patterns were formed by the constructs net hope, motor abilities, technical skills and the so far achieved percentage of the predicted adult height and how these patterns are related to subsequent sporting success. 119 young elite football players were questioned and tested three times at intervals of one year, beginning at the age of 12. At the age of 15, the performance level the players had reached was examined. At all three measuring points, four patterns were identified which displayed partial structural and high individual stability. As expected, the players showing values above average in all factors were significantly more likely to advance to the highest performance level. Physically strong, precocious developed players though having some technical weaknesses, have good chances to reach the middle performance level. The results point to the importance of holistic approaches for the prediction of performance among promising football talents in the medium-term and thus provide valuable clues for their selection and promotion.

Prevención de lesiones en el deporte. Claves para un rendimiento deportivo óptimo. Romero Rodríguez, Daniel y Tous Fajardo, Julio. Medica Panamericana D. L., Madrid, 2010

La obra presenta variados temas, alguno de los cuales son abordados en forma general y en otros los autores profundizan introduciendo al lector en el verdadero campo de la prevención. Dentro de estos temas dedican un capítulo a uno de los pilares más importantes para la determinación de puntos débiles, que es la valoración de los aspectos necesarios de la forma física en relación a la posibilidad de lesiones, es decir, poder determinar el perfil lesivo de cada deportista. Se presentan metodologías de tratamiento en la prevención de lesiones basadas en tres pilares fundamentales: enfoque neuromuscular, entrenamiento de la fuerza para orientar los tratamientos y priorizar el componente excéntrico del movimiento como base funcional para la prevención. Así mismo incorpora una metodología de trabajo por medio de la vibración

Prevención de lesiones en el deporte. Claves para un rendimiento deportivo óptimo. Romero Rodríguez, Daniel y Tous Fajardo, Julio. Medica Panamericana D. L., Madrid, 2010

La obra presenta variados temas, alguno de los cuales son abordados en forma general y en otros los autores profundizan introduciendo al lector en el verdadero campo de la prevención. Dentro de estos temas dedican un capítulo a uno de los pilares más importantes para la determinación de puntos débiles, que es la valoración de los aspectos necesarios de la forma física en relación a la posibilidad de lesiones, es decir, poder determinar el perfil lesivo de cada deportista. Se presentan metodologías de tratamiento en la prevención de lesiones basadas en tres pilares fundamentales: enfoque neuromuscular, entrenamiento de la fuerza para orientar los tratamientos y priorizar el componente excéntrico del movimiento como base funcional para la prevención. Así mismo incorpora una metodología de trabajo por medio de la vibración

Prevención de lesiones en el deporte. Claves para un rendimiento deportivo óptimo. Romero Rodríguez, Daniel y Tous Fajardo, Julio. Medica Panamericana D. L., Madrid, 2010

La obra presenta variados temas, alguno de los cuales son abordados en forma general y en otros los autores profundizan introduciendo al lector en el verdadero campo de la prevención. Dentro de estos temas dedican un capítulo a uno de los pilares más importantes para la determinación de puntos débiles, que es la valoración de los aspectos necesarios de la forma física en relación a la posibilidad de lesiones, es decir, poder determinar el perfil lesivo de cada deportista. Se presentan metodologías de tratamiento en la prevención de lesiones basadas en tres pilares fundamentales: enfoque neuromuscular, entrenamiento de la fuerza para orientar los tratamientos y priorizar el componente excéntrico del movimiento como base funcional para la prevención. Así mismo incorpora una metodología de trabajo por medio de la vibración