抄録
Exercise affects human immune functions through the hypothalamus-pituitary-adrenal (HPA) axis and reward
systems in the brain. Most immune cells, including T cells, B cells and phagocytes, express functional hormone
and neurotransmitter receptors and are regulated through the neuroendocrine immune network. Light-to-moderate
exercise improves the defense activity against pathogens and prevents metabolic disorders. Many epidemiological
and experimental studies have suggested there is an inverse relationship between moderate exercise training and
illness risk. Furthermore, habitual exercise might improve immune regulation, reduce the activity of autoimmune
disorders and delay age-related dysfunctions, such as sarcopenia. On the other hand, high-intensity exercise suppresses immune defense activity, especially against upper respiratory infections. Thus, high-intensity training and
competitions possibly increase the risk of infection in athletes. Appropriate nutritional intake and hygiene control
are also essential to protect both athletes and non-athletes.
