Appetite regulation via exercise prior or subsequent to high-fat meal consumption

This study assessed the effect of exercise timing relative to meal consumption on appetite and its hormonal regulators (i.e., PYY(3-36), ghrelin and leptin) in moderately active young men. Twelve men performed three trials in a random order: (1) meal consumption, (2) exercise 2h after a meal, (3) exercise 1h before a meal. The test meal provided 16.5 kcal kg(-1) with 70% fat, 26% carbohydrate and 4% protein. Exercise was performed at a work rate eliciting 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 7h after meal consumption. Exercise performed 2h 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 response to timing of exercise relative to food intake on plasma leptin concentration was detected. These data indicated the timing of exercise to meal consumption may influence appetite and its hormonal regulators. Post-meal exercise may extend the suppressive effects of meal consumption on appetite.