Antioxidants There has been a lot of research done in strength sports about antioxidants—betacarotene, vitamin C, vitamin E, and the minerals selenium, copper, zinc, and manganese. Antioxidants help fight free radicals, which form reactive oxygen species (ROS). These chemicals are produced naturally by the body and have historically been thought to cause irreversible damage (oxidation) to cells. Free radical oxidative damage can leave your body vulnerable to premature aging, cancer, cardiovascular disease, and degenerative diseases such as arthritis. Certain environmental factors such as cigarette smoke, exhaust fumes, radiation, excessive sunlight, certain drugs, and stress can increase free radicals and, ironically, so can the healthy habit of exercise. During respiration, cells pick off electrons from sugars and add them to oxygen to generate energy. As these reactions take place, electrons sometimes get off course and collide with other molecules, creating free radicals that roam throughout the body and create ROS. Exercise increases respiration, which produces more free radicals. Scientists have been intensely studying why this happens and may have discovered that the point of free radical production is not destruction, but a signal to the body to repair and grow—bigger, faster, and stronger. Interestingly, exercise not only increases production of ROS, it also induces the production of enzymes that fight ROS. Real damage occurs when the signaling system breaks down.