Physical Activity and Reward: The Role of Dopamine

Understanding the mechanisms underlying reward and motivation for physical activity has broad implications for improving health and longevity. A number of rodent animal studies have discovered neurobiological changes induced from chronic voluntary wheel running that are analogous to changes that take place in the brain in response to drugs of abuse. Additional neurobiological evidence that physical activity can be rewarding and reinforcing comes from a long-term selective breeding experiment for increased voluntary wheel running behavior in mice. The ventral tegmental area (VTA) is one of the two main locations in the brain where neurons are located that synthesize and release dopamine, and the projection of dopamine neurons from the VTA to the nucleus accumbens is considered a key component, or final common pathway, involved in the perception of reward and reinforcement. The specificity of dopamine involvement in physical activity reward as compared to a more general role in processing salient experiences or voluntary control of movement is difficult to establish.