ABSTRACT
Improvements in an athlete’s ability to tolerate and adapt to training stress are functions of the intensity, the duration, and the frequency of the stressors applied through the training program. Part of the adaptation process is the acceptance by the body of a particular level of stress into its normal homeostatic mechanisms. The effects of long-term training on humoral immunity in humans has again yielded variable results. There has been no evidence in marathon runners that levels of IgM, IgG, or IgA vary from normal, and marathon runners immunized with tetanus toxoid immediately following a race showed no impairment of their abilities to produce antibody. Animal studies have also indicated that the primary response to antigen is not influenced by long-term exercise. Several wide-ranging pharmacological therapies, including beta-adrenergic stimulants, methylxanthines, anti-cholinergics, alpha-adrenergic antagonists, and corticosteroids have been studied to determine their effects on exercise-induced asthma.
