Acute, but not chronic, exercise lowers the body weight set-point in male rats

The influence of muscular training on overall energy balance and body weight is not clear. A group of male rats was trained to feed every day from 1000 to 1200. Then the intersect of regression line of food hoarded during meal time vs. body weight with the X-axis was measured. Finally, the rats were trained to run 1 h every day on a motor-driven treadmill. When the training took place in the morning, just before the hoarding session, the mean intersect was significantly lowered from control (497 +/- 18 g to 433 +/- 9 g). When the training took place in the afternoon, after the hoarding session, the mean intersect was not significantly different (504 +/- 21 g) from control. Food intake during the hoarding sessions was affected neither by body weight changes nor by muscular exercise. These results suggest that the set-point for body weight regulation is acutely lowered just after muscular exercise, but is not influenced by chronic training.