Metabolic and hormonal consequences of two different meals after a moderate intensity exercise bout in obese prepubertal children

BACKGROUND/OBJECTIVES: To investigate the relationship between postprandial nutrient balance, satiety and hormone changes induced by two different meals taken after a moderate intensity exercise bout. SUBJECTS/METHODS: Ten prepubertal obese children participated in the study. The experiment was designed as a cross-over study for repeated measures. Each test period lasted five consecutive hours during which the children were under medical supervision. The effects of two isocaloric meals were compared after a moderate intensity exercise (4 multiples of resting metabolic rate, 30 min, cycling): a low-fat/high-carbohydrate meal (meal A) and a high-fat/low-carbohydrate meal (meal B). Pre and postprandial (3 h) substrate oxidation, biochemical parameters, gastrointestinal hormone concentrations and appetite were measured. RESULTS: The main results were: (i) higher fat balance (5.1 +/- 5.0 vs -5.0 +/- 6.6 g, P=0.001) and lower carbohydrate balance after meal B than A (-9.7 +/- 13.3 vs 11.3 +/- 18.3g. P<0.01); (ii) higher energy balance after meal B than after meal A (5.9 +/- 21.5 vs -13.9 +/- 20.2 kcal, P<0.05); (iii) higher plasma triglyceride concentrations (area under the curve) after meal B than after meal A (2962.5 +/- 2095.8 mg*180 min/dl vs - 169.5 +/- 1633.7 mg*180 min/dl, P<0.01); (iv) higher serum glucagon-like peptide-1 concentrations after meal B than after meal A (1101.5 +/- 873.0 pmoll*180 min/l vs 478.8 +/- 638.3 pmol*180 min/l, P<0.05). CONCLUSIONS: After a bout of moderate intensity exercise, a meal with a high-fat/low-carbohydrate ratio had a less favorable metabolic impact than an isoenergetic, isoproteic low-fat/high-carbohydrate meal.