Regulation of appetite by exercise performed before or after meal consumption

Effects of exercise timing relative to meal consumption on appetite and related hormonal regulators were studied in twelve moderately active men (19–36 years of age). Each subject performed three trials in random order: meal consumption only, exercise 2 hours after a meal, exercise 1 hour before a meal. The test meal provided 16.5 kcal/kg body weight with 70% as fat, 26% as carbohydrate and 4% as protein. The exercise bout was performed at 60% of VO 2max for 50 min. Hunger ratings and plasma leptin concentrations were measured at baseline and hours 1, 3, 5, and 7 post‐meal, and plasma concentrations of ghrelin and PYY 3–36 were measured at baseline and 1, 3, and 7 hours after meal consumption. Results indicated that exercise performed 2 hours after meal consumption extended the appetite suppressing effect of food intake. Furthermore, plasma PYY 3–36 concentration tended to be elevated by exercise after meal consumption. Exercise prior to food intake decreased appetite and increased plasma ghrelin concentrations. No clear response to timing of exercise relative to food intake on plasma leptin concentration was detected. These data suggest that timing of exercise around meal consumption may influence appetite and plasma concentration of some peptides that regulate food intake. Exercise may have a particularly beneficial effect on appetite suppression after consumption of a meal. Supported by the CA Dietetic Assoc.