산화스트레스와 항산화제 = Oxidative Stress and Antioxidants

다국어 초록 (Multilingual Abstract)

Performance of strenuous physical activity can increase oxygen consumption by 10 to 15-fold over rest to meet energy demands. The resulting elevated oxygen consumption produces an "oxidative stress" that leads to the generation of free radicals and lipid peroxidation. A defense system of free radical scavengers minimizes these dangerous radicals. Indirect measurements of free radicals generated during exercise include assessing products of lipid peroxidation that appear in the blood (e.g., malondialdehyde and conjugated dienes) or expired in the breath (pentane). Changes in antioxidant scavengers and associated enzymes (e.g., glutathione, tocopherol, glutathione peroxidase) also provide clues about demands on the defense system. Physical training has been shown to result in an augmented antioxidant system and a reduction in lipid peroxidation.
In recent years, much attention has been paid to the role antioxidants play in physical activity and physical performance. This attention is largely focused on the increase in free radicals generated during strenuous exercise. As oxygen consumption, and hence oxidative stress, is increased, free radicals are produced. Studies have reported that antioxidant supplementation can reduce evidence of exercise induced lipid perozidation. It has been suggested that those who engage in chronic physical activity, placing a constant oxidative stress on the muscles and other cells, may require additional antioxidants to help them recover from exercise. Other than their role in reducing tissue damage, the data are equivocal with respect to whether antioxidants will directly enhance physical performance. Antioxidant supplementation may be prepared to handle an sudden increase in oxidative stress.
Studies have shown increases in oxidative stress during performance of strenuous exercise and then supplementation would reduce this stress. The effects of antioxidant supplementation on physical performance are very affirmative.