"I Want a New Drug": Exercise as a Pharmacological Therapy.

Skeletal muscle can be considered a secretory organ that produces myokines and other humoral factors having autocrine-, paracrine-, and endocrine-like signaling effects throughout the body. Exercise has such profound pharmacological and physiological effects that it should be considered a drug therapy. Exercise has documented benefits for preventing or treating many physical and mental disorders or their sequelae, and it has a potential role in managing adverse effects associated with drug therapies. If exercise were a drug evaluated by the Food and Drug Administration, it might be approved for a large number of therapeutic indications. Exercise can be appropriately prescribed for virtually anyone for primary, secondary, or tertiary prevention of many mental and physical disorders.