The human immune system is a highly intricate network of cells and molecules designed to keep the host free from infection and disease. Exercise is known to have a profound impact on the normal functioning of the immune system. Having higher age and sex-adjusted scores for cardiorespiratory fitness and performing regular exercise of moderate- to vigorous-intensity exercise that fall within ACSM guidelines has been shown to improve immune responses to vaccination, lower chronic low-grade inflammation, and improve various immune markers in several disease states including cancer, HIV, cardiovascular disease, diabetes, cognitive impairment and obesity. The ongoing COVID-19 pandemic has raised a lot of questions regarding how exercise can protect us from infection by boosting immunity.
