Effects of voluntary and forced exercise on brain health in adult rats

Abstract

In an aging society, it is important to maintain brain health to improve quality of life. Exercise has many benefits for promoting brain health and neural plasticity. The effect of exercise is dependent on the style of exercise, and psychological factors such as motivation and stress associated with exercise have been reported to affect neuroplasticity. However, the most effective training methods and important factors are currently unknown. In the current study, we aimed to clarify the effects of stress and motivation associated with running on brain health in rats. The animals were assigned to voluntary wheel running (V-Run), forced treadmill running (F-Run), or sedentary groups. To investigate the motivation and stress associated with exercise, the expression of ΔFosB in the nucleus accumbens (NAc) and corticosterone concentration were compared after running. In the V-Run group, there was a significant increase in ΔFosB in the NAc, which is a key reward-related area. In the F-Run group, there was a high concentration of corticosterone after exercise. These data suggest that voluntary wheel running is a beneficial form of exercise for activating the brain-related reward system in rats. The psychological factors associated with running exercise might facilitate or mask activation and plasticity of brain because of the associated effects of motivation or stress.