Rúben Filipe Rocha

Effects of an Extrinsic Constraint on the Tennis Serve

This study analysed the extrinsic constraint of induced aerodynamic flow (IAF) on the first serve by expert tennis players with temporal organization of the movement, as well as the velocity and amplitude of the racket motion analyzed. Twelve expert right-handed tennis players voluntarily participated in this study. Each player performed 20 trials without IAF and another 20 trials for each different speed configuration of induced cross-wind: 2.4 m/s; 4.3 m/s; 5.8 m/s; and random speed. The coefficient of variation, r-pearson test and the inferential test one-way ANOVA were used to compare movement data. The results suggest spatio-temporal adjustments depending on the wind speed. Moreover, statistical differences were identified on both the temporal organization of the serve and on the rackets motion amplitude and velocity. The intra- and inter-individual variability of the motor behavior shows the uniqueness of the serve movement of each player.

Estudo da quantidade de jogadores em jogos reduzidos de handebol: mudança na dinâmica técnica e tática

O objetivo do presente estudo foi o de analisar os efeitos de diferentes formas de jogo (2 x 2, 3 x 3 e 4 x 4) de handebol no desempenho tecnico e tatico de alunos de Educacao Fisica. Participaram no estudo oito alunos do sexo masculino (18,25 ± 1,04 anos de idade). Os indicadores que apresentaram diferencas significativas foram: contatos na bola, numero de passes de ombro, passes de ombro completados e origem de pontos atraves de ataque organizado e contra-ataque. Conclui-se que as formas de jogo com menor numero de alunos aumentaram a quantidade de acoes tecnicas e taticas, sugerindo-se estas formas numa fase inicial de aprendizagem.