chapter  7
28 Pages

Effect of extreme environments on immune responses to exercise

Compared with exercise in thermoneutral conditions, exercise in hot conditions is associated with increased co re temperature, higher heart rate (cardiovascular drift), increased circulating stress hormones and an increased reliance on carbohydrate as a fuel source (Galloway and Maughan 1997; Febbraio 2001). Unsurprisingly, compared with thermoneutral conditions, endurance performance in the heat is impaired (Galloway and Maughan 1997; Ely et aL 2010). Exercising in hot conditions in which core temperature rises by more than 1°C compared with thermoneutral conditions (where core temperature rise is less than 1°C) augments anticipated increases in circulating stress hormones, including catecholamines and cytokines, with associated elevations in circulating leukocyte counts (Cross et aL 1996; Rhind et aL 2004).