Acute effects of exercise or sauna on appetite in obese and nonobese men

Abstract

To study the effect of exercise on appetite in men, hunger, thirst, taste perception, energy intake, and macronutrient choice were assessed in relation to exercise and to sauna; the latter was done to correct for dehydration and rise in body temperature. Since exercise is used to prevent and cure obesity, subjects included obese as well as nonobese men. Thirty subjects (25 +/- 7 years, BMI 22.8 +/- 1.6 and 28.5 +/- 1.9) were given twice, in random order before and after 2 h of cycling at 60% of Wmax, 2 h of sauna, or 2 h of rest, an ample choice from solid and liquid almost single-macronutrient food items and a taste perception test with solutions of sucrose, citric acid, NaCl, quinine, a mixture of these, and a carbohydrate electrolyte solution. After cycling as well as after sauna, in comparison to after rest, subjects lost 3 +/- 0.5% of body mass, while thirst, fluid intake, perception of sweet at relatively low concentrations, and percentage of energy coming from carbohydrate increased significantly. Only after cycling compared to after rest did perception of bitterness at a low concentration increase and hunger and energy intake decrease. We conclude that exercise induced a short-term reduction in hunger and energy intake, whereas exercise and sauna induced a short-term increase in taste perception of sweet at the lower concentration, while macronutrient preference of carbohydrate increased.