EFFECT OF PHYSICAL EXERCISE DURATION ON DECISIONAL PERFORMANCE

Abstract

Summary.- The purpose of this study was to measure the effect of exercise duration concomitantly on energy expenditure and cognitive performance. The physical task was pedalling on a cycloergometer at an intensity of 60% Pmax (power reached with maximal aerobic power). The cognitive task was a visual choice reaction task (RT2). Twenty-two students without expertise in decisional activities participated over four sessions procedure during 10 treatment days. In a first session, individual Pmax was measured. The second session (session 2) was composed by RT tasks performed at rest. During the sessions 3 and 4 randomly presented, each subject completed a 10 min. bicycle ergometer test without or with a simultaneous RT task. Mean RT values, error RT values, pedal rate were collected in sessions 2 and 4 at the beginning (3-5 min) and at the end (8-10 min) of the exercise test. Heart rate was continuously recorded. The results showed a significant interaction effect between cognitive task and exercise duration for mean RT values (p < .025), heart rate values (p < .025) whereas it was not significant for the R T eITor rate and peda1 rate. With exercise duration, mean RT presented higher decrease at the end of the exercise testing (p < .01). These results are discussed principally in terms of intermediaries factors as activation or investment of attentional resources induced by exercise duration.