Effects of Caffeine Supplementation on Oxidative Stress, Exercise- Induced Muscle Damage and Leukocytosis

The possible pathways of oxidative stress in anaerobic exercise includes transient and acute muscular deoxygenation, which resembles the ischemiareperfusion, xanthine oxidase activation, catecholamine autoxidation, and NADPH oxidase activation, prostanoid metabolism, phagocyte respiratory burst activity, disruption of iron containing proteins, and altered calcium homeostasis. 5 Mechanical stress is also another hypothesis used to explain the increment of free radicals. 6 The muscle tissue damage caused by high levels of force, initiates the inflammation process that eventually produces oxygen free radicals and lipid peroxidation. In addition, the strong muscle contractions during exercise may cause micro-tears both in muscle and in the vascular endothelium, which also affect the migration of white cells. 7 This damage leads to a temporary loss of the exercising capacity of muscle for force production and has implications for increase in muscle post exercise soreness. 8 Tidball reported that muscle micro-damage is an inflammatory factor during and after exercise. 9