Some supplements can blunt the positive effects of exercise training
In the fickle world of sports nutrition fads, few trends have shown the staying power of antioxidants. For more than three decades, athletes have remained devoted fans of supplements; the American College of Sports Medicine estimates that around half of elite athletes take vitamins in hopes of keeping their bodies fit and boosting endurance.
The idea makes intuitive sense: Energy consumption within a cell leaves a trail of spent oxygen molecules that can damage tissues and contribute to fatigue. Although the body has internal garbage collectors to clean up the waste products of metabolism, the demands of strenuous physical activity overwhelm the system. Cells need a boost. Food can supply antioxidants naturally — some of the best known are vitamins C and E — but why rely on vegetables when pills or sports drinks can deliver hundreds of times the vitamin E