INFLUENCE OF THE COMPOSITION OF A MEAL TAKEN AFTER PHYSICAL EXERCISE ON MOOD, VIGILANCE, PERFORMANCE

The metabolic and behavioral effects of nutrients after exercise on vi gilance level, performance, and mood have been minimally studied and h ave given contradictory results. In order to increase the understandin g of the relationships between nutrition, exercise and performance, th is experiment compared the effects on mood and performance of a protei n- rich meal and a protein- poor meal, eaten just after an acute sessi on of exercise. Vigilance and mood were evaluated by visual analog sca les, and memory was measured by memory search task from the AGARD STRE S battery, based on the Sternberg paradigm. Forty-two subjects were in volved in this experiment. All subjects participated in the study of t he effect of exercise after two kinds of meals (protein and nonprotein ). Two groups of fourteen subjects we used to evaluate the effect of t he exercise and the effect of the delay of meal intake after exercise in the two kinds of diet. The results show no difference in memory per formance between exercise and rest conditions, nor between ''protein'' and ''no protein'' meal groups. They do show, however, that subjects feel happier after a meal with protein than after a meal without prote in. The effects of the ''no protein'' meal on drowsiness differ with t he glucide content of the meal. subjects are less drowsy when they eat between 125 and 150 g of glucide than when they eat more than 150 g. The rousing effect induced by physical exercise is counterbalanced whe n subjects eat more than 150 g of carbohydrate. The anxiolytic effect of glucide is re-established. (C) 1998 Elsevier Science Inc.