Overview of Mechanisms of Action of Exercise in Psychiatric Disorders and Future Directions for Research

Abstract As discussed in previous chapters, evidence supporting the use of exercise in the treatment of psychiatric disorders continues to grow. This chapter summarizes some of the work done to elucidate the biological mechanisms underlying the positive psychological effects of exercise, focusing on five neurobiological mechanisms: serotonin, dopamine, the hypothalamic-pituitary-adrenal axis, endocannabinoids, and brain-derived neurotrophic factor. Furthermore, this chapter discusses the potential clinical implications of identifying the mechanisms by which exercise improves mental health. In understanding these mechanisms, it is hoped that clinicians will be able to identify patients most likely to benefit from exercise treatment while providing an alternative treatment for those unlikely to benefit. As evidence supporting the positive effects of exercise on psychological disorders has accumulated, additional research has aimed to identify the biological mechanisms underlying these effects. Just as the mechanisms underlying psychiatric disorders are wide-ranging (Nestler et al., 2002), the potential mechanisms by which exercise influences neurobiology are equally diverse. In a seminal review, Dishman et al. (2006) described the extensive neurobiological effects of exercise, highlighting neurotrophic mechanisms, attenuation of the negative effects of stress, and brain metabolism. This chapter will provide an overview of some of the potential mechanisms underlying the effects of exercise on mental health and discuss how these mechanisms can ultimately inform clinical decision-making to improve treatment outcomes in psychiatric disorders.