ABSTRACT
The high incidence of upper respiratory illness (URI) among competitive athletes has prompted studies on the effects of exercise on mucosal immunity. IgA, the major effector of mucosal immunity, has been shown to decrease following intense endurance exercise. There is a general perception among elite athletes, their coaches and team physicians that athletes are susceptible to URI during intense sports training and major competitor. This perception has been supported by epidemiological data. The high frequency of recurrent URI among elite athletes has prompted a number of studies on the effects of exercise on mucosal immune function, and especially IgA, the major immunoglobulin class in mucosal fluids. Decreases in salivary IgA levels have been noted following intense endurance exercise in a variety of athletes, such as cross country skiers, cyclists, swimmers, runners, and hockey player. Psychological stress has been shown to decrease salivary IgA levels.
