Background

Diet-induced obesity in mice can be mitigated by prolonged periods of exercise, despite increased high-fat food intake, by increasing energy expenditure.We assessed the impact of short periods of voluntary wheel running on weight gain and high-fat food intake behavior.

Methods

Male C57Bl/6N mice were fed high-fat food ad libitum.For 30 minutes on 5 days per week for a total of 5 weeks, mice were also were provided with an in-cage running wheel.The running wheel was either open, allowing voluntary exercise, or locked and could not rotate as a control.Weight gain, fat mass, food intake, and eating behavior were assessed.

Results

Wheel running significantly reduced weight gain and fat mass.Wheel running also reduced energy intake.Mice pair-fed to wheel running mice, but instead had a locked running wheel, showed similar reductions in weight gain and fat mass.Wheel running mice had shorter, smaller, and more frequent eating episodes compared to controls.Nocturnal and diurnal feeding rhythm was unchanged.

Conclusions

Short periods of voluntary wheel running reduces weight gain in mice by decreasing high-fat food intake.Coincident changes in meal size, duration, and frequency may also contribute.Voluntary wheel running for 30 minutes on 5 days per week can serve as a clinically relevant model to study the physiological mechanisms underlying the benefits of exercise on food intake behavior and obesity prevention.