Influence of brisk walking on appetite, energy intake, and plasma acylated ghrelin

Purpose: This study examined the effect of an acute bout of brisk walking on appetite, energy intake, and the appetite-stimulating hormone-acylated ghrelin. Methods: Fourteen healthy young males (age 21.9 +/- 0.5 yr, body mass index 23.4 +/- 0.6 kg.m(-2), (V) over dotO(2max) 55.9 +/- 1.8 mL.kg(-1).min(-1); mean +/- SEM) completed two 8-h trials (brisk walking and control) in a randomized counterbalanced fashion. The brisk walking trial commenced with 60 min of subjectively paced brisk walking on a level-motorized treadmill after which participants rested for 7 h. Participants rested for the duration of the control trial. Ad libitum buffet meals were offered twice during main trials (1.5-2 and 5-5.5 h). Appetite (hunger, fullness, satisfaction, and prospective food consumption) was assessed at 30-min intervals throughout. Levels of acylated ghrelin, glucose, insulin, and triacylglycerol were determined from plasma. Results: Sixty minutes of brisk walking (7.0 +/- 0.1 km.h(-1)) yielded a net (exercise minus resting) energy expenditure of 2008 +/- 134 kJ, yet it did not significantly influence appetite, energy/macronutrient intake, or the plasma concentration of acylated ghrelin either during or after exercise (P > 0.05). Participants did not compensate for energy expended during walking, therefore a deficit in energy was induced (1836 kJ, 439 kcal) relative to control. Conclusions: This study demonstrates that, despite inducing a moderate energy deficit, an acute bout of subjectively paced brisk walking does not elicit compensatory responses in acylated ghrelin, appetite, or energy intake. This finding lends support for a role of brisk walking in weight management.