Abstract The objective of this study was to develop a viable and low-cost model of voluntary physical exercise that could be applied to studies on metabolism and behavior. 40 male zebrafish (Danio rerio) were studied, divided into two groups: control and voluntary physical exercise. The model consisted of two aquariums connected by a translucent tube and a video camera on the side to measure physical exercise parameters of the animals. The animals showed higher acceleration and maximum speed and had a higher frequency of activity in the light period. In this model of voluntary physical exercise, we observed better performance in locomotor assessment tests, which was not accompanied by increased anxiety or changes in biochemical parameters related to lipid metabolism. Zebrafish responded positively to voluntary physical exercise and this model appears to be a good option for further studies. lowcost low cost behavior 4 Danio rerio studied groups period tests

Resumen El objetivo de este estudio fue comparar las variables antropométricas y de potencia de miembros inferiores (PMI) en una muestra de jugadores de rugby-7 de diferentes posiciones. Participaron 22 jugadores universitarios clasificados de acuerdo con las posiciones ocupadas en el terreno de juego en back y forward. Para evaluar el porcentaje de grasa, se utilizó el protocolo de 7 pliegues cutáneos de Jackson & Pollock, y para las pruebas de PMI salto vertical (CMJ), salto horizontal y salto triple. Con el afán de comparar las variables del estudio, fue adoptado el test T para muestras pareadas, siendo el p < 0,05. Los resultados indicaron una diferencia significativa entre la masa total (t = , p < 0,01), la masa libre de grasa (p < 0,05), la masa adiposa (p < 0,01) y el CMJ (p < 0,005) entre los grupos. Se observa que las características antropométricas y neuromusculares para los forwards son distintas de las de los backs, debido a la posición de juego, que requiere una configuración morfológica y física distinta.

Resumo O objetivo deste estudo foi comparar as variáveis antropométricas e de potência dos membros inferiores (PMI) em uma amostra de jogadores de rúgbi-7 de diferentes posições. Participaram 22 jogadores universitários, classificados de acordo com as posições ocupadas no campo de jogo para adiante e para trás. Para avaliar o percentual de gordura, utilizou-se o protocolo de 7 dobras cutâneas de Jackson & Pollock, e para os testes de PMI salto vertical (CMJ), salto horizontal e salto triplo. Com o objetivo de comparar as variáveis do estudo, o teste T foi adotado para amostras de dupla, sendo p <0,05. Os resultados indicaram uma diferença significativa entre a massa total ( t =, p <0,01), a massa livre de gordura (p <0,05), a massa adiposa (p <0,01) e o CMJ (p < 0,005) entre os grupos. Observa- se que as características antropométricas e neuromusculares para os atacantes são diferentes daquelas das costas, devido à posição de jogo, que requer uma configuração morfológica e física diferente.

Abstract The objective of this study was to compare the anthropometric and lower limb power (PMI) variables in a sample of rugby-7 players holding different positions. Twenty-two rugby-7 college players participated; according to the positions occupied on the playing field, they were classified in back and forward. The protocol of seven skin folds of Jackson & Pollock was used to evaluate the percentage of fat; and for the PMI tests vertical jump (CMJ), horizontal jump and triple jump. The T-test for paired samples was adopted, being p < 0.05, to compare the study variables. The results indicated a significant difference between the total mass (p < 0,01), the fat-free mass (p < 0,05), the fat mass (p < 0,01), and the CMJ (p < 0,005) between the groups. It is observed that the anthropometric demands for the forwards are different from the backs, due to the characteristic of the game position, which requires a different physical and morphological configuration.