Free radicals are atoms or groups of atoms that have at least one unpaired electron, which makes them highly reactive. Free radicals promote beneficial oxidation that produces energy and kills bacterial invaders. In excess, however, they produce harmful oxidation that can damage cell membranes and cell contents.
Where does Free Radicals Come From?
Endurance exercise can increase oxygen utilization from 10 to 20 times over the resting state. This greatly increases the generation of free radicals, prompting concern about enhanced damage to muscles and other tissues. So the question now is, how effectively can athletes defend against the increased free radicals resulting from exercise? Do athletes need to take extra antioxidants?
When an oxygen molecule (O2) becomes electrically charged or "radicalized" it tries to steal electrons from other molecules, causing damage to the DNA and other molecules. Over time, such damage may become irreversible and lead to disease including cancer. Antioxidants are often described as "mopping up" free radicals, meaning they neutralize the electrical charge and prevent the free radical from taking electrons from other molecules.
Several interesting concepts have emerged from these types of experimental studies. Regular physical exercise enhances the antioxidant defense system and protects against exercise induced free radical damage. This is an important finding because it shows how smart the body is about adapting to the demands of exercise. These changes occur slowly over time and appear to parallel other adaptations to exercise.
What does Antioxidants Do?
Antioxidants play the housekeeper's role, "mopping up" free radicals before they get a chance to do harm in your body. Researchers have postulated that antioxidants prevent the possible carcinogenic effects of oxidation. Despite numerous studies carried out on the role of antioxidants in cancer and heart disease prevention, the jury is still out as to which groups of people, if any, benefit from taking antioxidant supplements.
Considerable evidence now suggests that oxidants are involved in the development and clinical expression of coronary heart disease and that antioxidants may contribute to disease resistance.
