Research on the association between physical activity and mental health addresses the beneficial effects of physical activity on emotional and cognitive functioning. With regard to emotional functioning, most studies focus on the influence of physical activity on depressive symptoms or affective disorders. These studies show that the beneficial effects of aerobic exercise and pharmacotherapy on depressive symptoms seem to be comparable and discuss a variety of neurobiological mechanisms that improve symptoms. The positive effects of physical activity on anxious mood and anxiety disorders are also well documented. Desensitization to physiological changes, improved self-esteem, and self-efficacy seem to play an important part. However, aerobic exercise does not improve mental health in every case, as seen for instance in over-trained athletes. Research on the relationship between physical activity and cognitive functioning reveals that physical activity can prevent the age-related cognitive decline and can delay the onset of dementia. Physical activity has beneficial effects not only on adults but also on children's and adolescents' mental health and cognitive performance, particularly on their executive functions that are still developing throughout adolescence. Finally, physical activity also affects the endocrine stress-regulation system: trained people reveal stronger reactivity and quicker regeneration when faced with stressful events.
