Variabilidade inter-individual na estrutura temporal do arremesso no basquetebol / Inter-individual variability in temporal structure of the basketball shoot

Este estudo analisou a variabilidade inter-individual na estrutura temporal aplicada no arremesso no basquetebol. Dez atletas masculinos experientes em basquetebol foram filmados e um número de parâmetros cinemáticos do movimento analisados. Um modelo biomecânico forneceu os tempos relativos dos movimentos das articulações do ombro, do cotovelo e do punho. A variabilidade inter-individual foi analisada por meio da sequência e do tempo relativo de dez fases do arremesso. Para comparar a variabilidade das fases do arremesso entre os sujeitos foi utilizada uma Análise Discriminante e uma ANOVA. O teste de Post Hoc de Tukey foi aplicado para determinar onde as diferenças ocorreram. O nível de significância foi de p = 0,05. A variabilidade inter-individual foi explicada por três fatores atuando concomitantemente: estratégia de controle da (a) precisão e (b) da geração de velocidade, e (c)características intrínsecas dos sujeitos. Portanto, ainda que algumas ações sejam comuns aos padrões de arremesso no basquetebol, cada arremessador demonstrou características particulares e individuais.

This study analyzed inter-individual variability of the temporal structure applied in basketball throwing. Ten experienced male athletes in basketball throwing were filmed and a number of kinematic movement parameters analyzed. A biomechanical model provided the relative timing of the shoulder, elbow and wrist joint movements. Inter-individual variability was analyzed using sequencing and relative timing of tem phases of the throw. To compare the variability of the movement phases between subjects a discriminant analysis and an ANOVA were applied. The Tukey test was applied to determine where differences occurred. The significance level was p = 0.05. Inter-individual variability was explained by three concomitant factors: (a) a precision control strategy, (b) a velocity control strategy and (c) intrinsic characteristics of the subjects. Therefore, despite the fact that some actions are common to the basketball throwing pattern each performed demonstrated particular and individual characteristics.

Imagery intervention in open and closed tennis motor skill performance.

To assess use of imagery intervention in performance of two tennis motor skills the quasi-experimental design included a pre- and posttest and a control group. The tennis service shot and service receiving skill were selected as representative of open and closed skills, respectively. 48 subjects, male tennis players, whose ages ranged from 16 to 18 yr. (M = 17.2), were divided into two groups: (1) Technical practice only which was used as control group and (2) Imagery group who received both imagery and technical practice. Analysis of covariance showed a significant main effect for the imagery intervention on the closed skill (p = .002). Findings suggest that imaging a positive outcome may be more powerful in improving performance of closed skill movements than of open skill movements.