A strong immune system equips the body with the defenses necessary to fight infectious diseases and cancers and assists in recovering from illness. Due to the Covid-19 pandemic there is no time like the present to work on improving yours. A brief increase in body temperature during and directly following exercise may prevent bacteria from growing and may also help the body fight infection. Exercise helps regulate the autonomic nervous system which is responsible for regulating body temperature. Moderate exercise has been shown to bolster the function of certain components of the human immune system-such as natural killer cells, circulating T-and B-lymphocytes, and cells of the monocyte-macrophage system- thereby possibly decreasing the incidence of some infections.