Nutritional Interventions to Reduce Immune Suppression Post Marathon

In elite level athletes it is commonly believed that there is a link between high-intensity exercise and increased incidence of upper respiratory tract infections (URTI). Physiological changes associated with exercise are well documented on various components of the immune system, including: changes in number of circulating immune cells and their responsiveness, changes in cytokines and chemokines, and changes in mucosal IgA levels. This chapter uses the example of long-distance running to review what is known about the link between intense exercise and URTI incidence, and changes in various immune system parameters after intense exercise. Finally, the ability of nutritional interventions to rebalance the immune system parameters affected by strenuous exercise are reviewed with an emphasis on the ability of yeast beta glucan to mitigate the negative impact of exercise on the immune system.