Acute Exercise-Induced Energy Expenditure and Substrate Oxidation Rates Might Not Be Associated With Subsequent...

While acute exercise has been shown to alter subsequent energy intake in adolescents with obesity, the role of the exercise-induced energy expenditure and substrate oxidation remains unknown. The present study investigates the effect of energy expenditure and substrate oxidation rates during an acute walking exercise on subsequent appetitive responses in adolescents with obesity.

Body composition and maximal aerobic capacities were assessed in 25 adolescents [8 males, 12-16 years] with obesity. They then realized a control condition without exercise [CON] and an exercise session [EX, 40-min walking at 4 km h^-1] in a randomized order. Energy expenditure and substrate use were assessed at rest and during exercise using indirect calorimetry. Subsequent ad libitum energy intake, appetite sensations and food reward were assessed.

Post-exercise energy intake was reduced on EX compared with CON [1083 ± 253 vs. 950 ± 226 kcal; p = 0.041], with reduced absolute protein intake [p = 0.011]. None of the appetite sensations differed between conditions. Pre-lunch explicit liking for fat decreased on EX compared with CON [p = 0.045], the implicit and explicit wanting for fat [p = 0.047 and p = 0.025 respectively] and explicit wanting for taste [p = 0.012] decreased from pre to post lunch after exercise. Energy Expenditure, fat and carbohydrate oxidation rates during exercise were not associated with subsequent appetitive measurements.

Exercise-induced energy expenditure and substrate might not be associated with the short-term control of appetite and energy intake in adolescents with obesity, which remains to be confirmed by further studies evaluating the effect of various exercises inducing specific predominant fuel sources.