The evaluation of performance through the application of adequate physical tests during a sportive season may be a useful tool to evaluate training adaptations and determine training intensities. For runners, treadmill incremental VO(2)max tests with gas exchange analysis have been widely used to determine maximal and submaximal parameters such as the ventilatory threshold (VT) and respiratory compensation point (RCP) running speed. However, these tests often differ in methodological characteristics (e.g., stage duration, grade, and speed increment size), and few studies have examined the reproducibility of their protocol. Therefore, the aim of this study was to verify the reproducibility and determine the running speeds related to maximal and submaximal parameters of a specific incremental maximum effort treadmill protocol for amateur runners. Eleven amateur male runners underwent 4 repetitions of the protocol (25-second stages, each increasing by 0.3 km·h in running speed while the treadmill grade remained fixed at 1%) after 3 minutes of warm-up at 8-8.5 km·h. We found no significant differences in any of the analyzed parameters, including VT, RCP, and VO(2)max during the 4 repetitions (p > 0.05). Further, the results related to running speed showed high within-subject reproducibility (coefficient of variation < 5.2%). The typical error (TE) values for running speed related to VT (TE = 0.62 km·h), RCP (TE = 0.35 km·h), and VO(2)max (TE = 0.43 km·h) indicated high sensitivity and reproducibility of this protocol. We conclude that this VO(2)max protocol facilitates a clear determination of the running speeds related to VT, RCP, and VO(2)max and has the potential to enable the evaluation of small training effects on maximal and submaximal parameters.

INTRODUÇÃO: Exércitos do mundo inteiro reconhecem a importância de uma boa condição física para o desempenho das funções militares. O treinamento físico militar (TFM) tenta proporcionar auxílio nessa busca por uma melhor condição física e corporal. OBJETIVO: Verificar o efeito de 13 semanas de TFM na composição corporal e no desempenho físico dos alunos da Escola Preparatória de Cadetes do Exército (EsPCEx). MÉTODOS: A amostra foi constituída de 287 alunos do sexo masculino da EsPCEx com idade média de 18,33 ± 1,26 anos. Tais alunos cumpriram uma rotina de internato, com horários, refeições e atividades definidas, da qual eram liberados somente nos finais de semana. O TFM foi realizado numa frequência semanal de cinco dias e englobou treinamentos aeróbicos e resistivos. Foram realizadas no período pré e pós-treinamento medidas da massa corporal, altura, dobras cutâneas (tricipital, abdominal e suprailíaca) e realizados os seguintes testes: corrida de 12 minutos, abdominal parafuso, flexão de braço e flexão na barra fixa. Com os dados antropométricos coletados, foi calculado o percentual de gordura, massa livre de gordura (MLG) e massa gorda (MG) baseado no protocolo de três dobras de Guedes. RESULTADOS: Quando comparados os valores dos dados antropométricos e da composição corporal dos períodos inicial e final de treinamento foi observada redução significativa na MG, no percentual de gordura, nas dobras cutâneas tricipital e abdominal e aumento na dobra cutânea suprailíaca e na MLG. Ocorreram melhoras significativas também em todos os testes físicos realizados, nos quais um melhor desempenho foi alcançado. CONCLUSÃO: Os dados obtidos sugerem melhora significativa na composição corporal e no desempenho físico através da realização do TFM, com frequência semanal de cinco dias.

Introduction: Knowing which physiological variables predict running performance could help coaches to optimize training prescription to improve running performance. Objective: The present study investigated which physiological respiratory responses could predict 3000-m running performance. Methods: Seventeen amateur runners (29.82±7.1years; 173.12±9.0cm; 64.59±9.3kg) performed a maximal graded running test on a treadmill. The ventilatory threshold (VT), respiratory compensation point (RCP), and maximal oxygen consumption (VO2max) were assessed, as well as the respective velocities (vVT, vRCP, vVO2max). After 72 to 96 hours the runners performed the 3000-m running field test. The relationships between variables were performed using Pearson product momentum correlations. Thereafter, simple and multiple regression models were applied. The significance level adopted was 5% (p<0.05). Results: The majority of physiological responses were positive and well related to each other (r≥0.70; p<0.05). Despite vVT, vRCP, and vVO2max demonstrating a higher and inverse relationship with 3000-m time (r=-0.92; r =-0.96; r =-0.89; p<0.05), the multiple regression model indicated that vRCP and vVO2max are the best variables to predict 3000-m performance in experienced amateur road runners (R2=0.94). The equation proposed by the model was: 3000-m(s)=1399.21–[31.65*vRCP(km.h-1)]–[12.06*vVO2max (km.h-1)]. Conclusion: The vRCP and vVO2max may be used to predict 3000-m performance using only a maximal running test on a treadmill. In practical terms, coaches and physical conditioners can use performance in the 3000-m to select different exercise running intensities to prescribe exercise training intensities.

No abstract

RESUMOO objetivo deste estudo foi verificar as respostas eletromiográficas dos músculos reto abdominal e oblíquo externo durante a realização do exercício abdominal -crunch‖. Participaram no estudo 13 universitários de ambos os sexos (18 a 23 anos). O exercício abdominal crunch foi realizado até à exaustão, com sobrecargas de 20, 40, 60 e 80% da contração voluntária máxima (CVM). Os valores (mediana e semi-amplitude interquartílica) das três primeiras e três últimas repetições de cada carga foram expressos em root-mean-square (RMS). Observou-se um aumento nos valores de RMS das últimas repetições em relação às primeiras repetições na carga de 20%, nas duas primeiras na carga de 40% e na primeira repetição na carga de 80%. Não houve diferença em relação à carga de 60%. Os resultados demonstram que a utilização de sobrecargas no exercício abdominal pode ser uma alternativa de distinção da intensidade da aplicação do exercício de força, no que se diz respeito à variável intensidade da carga, o que pode tornar-se uma ferramenta prática e útil para ser aplicada em sujeitos que desejam aumentar o nível de força abdominal. Palavras-chave: exercício abdominal "crunch", reto abdominal, obliquo externo, fadiga, sobrecarga, eletromiografia ABSTRACTThe purpose of this study was to verify the electromyographic activity of the rectus abdominis and obliquus externus abdominis during abdominal crunch exercise performed with maximum and submaximum loads. Thirteen male and female university students participated in this investigation (18-23 years old). The subjects completed abdominal crunch exercise until exhaustion with 20, 40, 60 and 80% of the maximum load. The root-mean-square (RMS) from electromyography activity of the rectus abdominis and obliquus externus muscles from the first and last three repetitions from each workload performed was analyzed. RMS for the last repetitions increased in relation to the first repetitions for the 20% workload, first two repetitions on 40% workload and first repetition on the 80% workload. There was no difference for the 60% workload. Results showed that external load on abdominal crunch exercise might be an alternative to increase intensity while performing abdominal crunch exercise, which on its turn can be a practical tool for subjects that aim to increase abdominal strength level.

Practical approach for the study of metabolic regulation.

The aim of the present study was to evaluate the age and inter- and intra-position differences in the anthropometric variables and physical performance in young female players of Brazilian women's volleyball. Fifty-eight female volleyball players participated, divided into 3 age groups: (a) 14 and under (n=20; mean age = 12.6±0.7 years), (b) between 14 and 17 (n=31; mean age = 15.6±1.2 years), and (c) over 17 (n=7; mean age = 18.9±0.9 years). In addition, the players were also divided according to their positions: setters (n=7), opposites (n=13), passer-hitters (n=17), middle blockers (n=12) and liberos (n=9). Anthropometric characteristics, flexibility, strength / resistance abdominal muscles, pushups, explosive power of the arms, jumping abilities, shuttle run and 20-m sprint tests were evaluated. Analyses showed differences among age and playing positions for the height and bone mass (p<0.05). In the fitness assessment, no differences were found between playing positions (p>0.05). However, differences were found among for age groups horizontal jump, shuttle run and 20-m sprint, with players >17 performing better than <14 and between 14-17 years of age (p<0.05). These results demonstrated that the height, bone mass and horizontal jump, shuttle run and 20-m sprint are age dependent, while physical performance independent on the playing positions.

Building the glycolisis and Krebs cycle as a puzzle: a strategy to learning metabolic pathways.