Influence de l'effort physique sur le temps de réaction simple et de choix chez des basketteurs de haut niveau

Abstract

Cette étude a pour but d'évaluer l'effet de l'effort physique sur les performances de jeunes sportifs dans des tâches de temps de réaction simple et de choix. Huit sujets, membres de l'équipe de France cadette de basket-ball, effectuent deux épreuves de course sur tapis roulant à différentes valeurs relatives (90% et 125%) de leur puissance maximale aérobie. Pendant et au terme de ces efforts, ils réalisent des tâches de temps de réaction simple (TRS) et de temps de réaction de choix (TRC). On mesure les performances et la fréquence cardiaque. Les résultats montrent: une amélioration postexercice du TRS et du TRC; une dégradation durant l'exercice du TRS; une amélioration durant l'exercice du TRC, avec cependant une augmentation du nombre d'erreurs. La discussion porte sur les influences diversifiées du niveau d'activation, des demandes des tâches de production d'effort, de l'expertise et de la condition physique des sujets, sur les facteurs de la performance dans les tâches de temps de réaction. The aim of this study was to investigate the effect of exertion on performance of young sportsmen in simple and choice reaction time tasks. Eight subjects performed two running exercises on a treadmill, at 90 and 125% of their aerobic maximal power. During and after this exercise, they performed cognitive tasks of simple reaction time (SRT) and choice reaction time (CRT). Reaction time and heart rate (HR) data were collected. During reaction time tasks, HR were significantly increased at the end of tests. In all exercises, results indicated a significant deterioration of SRT during exercise and an improvement of CRT with, nevertheless, an increasing number of errors. Likewise, during recovery, SRT and CRT were significantly facilitated. The discussion focused on the diverse influences of activation level, exertion task demands, subjects expertise and physical fitness on performance factors in reaction time tasks. The overall post-exercise facilitation, of subjects performance in SRT and CRT can be explained by a general improvement in the arousal level. The deterioration in SRT during exertion seems to confirm the inverted U hypothesis. However, conflicting results may not allow us to dismiss an effect of the exercise task; this would lead one to a competitive demand in processing ressources that can be allocated in the reaction time task. With regard to the facilitation of CRT, we can note, however that this is significant only for supramaximum levels of exertion. The increase in numbers of errors, together with this facilitation, led us to ask if some of the correct answers were not anticipated. This asked for the strategy equation used by some subjects. The facilitation of CRT, without an increase in numbers of errors, in a trained and skilled population in a physical activity with a high level of uncertainty, showed us that this can represent a real improvement of the decision process. The results prove the importance to consider, for this type of research on cognitive processes, the effect of expertise and competitive physical speciality.