Exercise Interventions as the Primary Treatment for Depression: Evidence from a Narrative Review.

There is an increasing evidence supporting the efficacy of exercise interventions in the treatment of depression, which is a growing global health concern. However, data on the efficacy of exercise as the primary treatment for depression are scarce. This narrative review explored the efficacy of exercise interventions as the primary treatment for depressive disorders. A comprehensive search for English-language literature published between January 1965 and November 2019 was conducted via PubMed, Google Scholar, Scopus, Web of Science, PsycINFO, EMBASE, Cochrane database and Medline. Thirteen randomised control trials (RCTs) were included in the final analysis. Their results indicated that supervised aerobic exercise and high-intensity progressive resistance training (PRT) were effective in ameliorating depressive symptoms as the primary treatment compared with control groups, but they were not superior to other active treatments, such as antidepressants and cognitive behavioural therapy. Aerobic exercise and high-intensity PRT may be a promising primary treatment for depression as they may induce biopsychosocial effects (effects on neurotrophic factor, pro-inflammatory cytokines, monoamine, the hypothalamic-pituitary-adrenal axis, self-efficacy, mastery experience, adaptive coping and social interaction), which may ameliorate the severity of depressive symptoms. However, future RCTs with more comprehensive and well-designed methodologies are warranted to confirm our findings.