Vitamin and mineral supplementation and exercise performance
Zimmermann MB.
Supplements of vitamins C and E have shown promise in reducing exercise-related symptoms (delayed muscle soreness) and biochemical indices of oxidative stress in both trained and untrained individuals. However, these antioxidant supplements appear to have no beneficial effect on performance and more research is needed to prove their long-term use is safe and effective. A prudent recommendation for athletes is to consume a diet rich in antioxidants. For female athletes, vegetarian athletes, and distance runners, daily consumption of foods rich in bioavailable iron together with periodic monitoring of iron status will minimize risk of iron deficiency. Iron supplementation is clearly indicated for cases of iron-deficiency anemia and may be beneficial in cases of low serum ferritin without anemia. The effect of magnesium (Mg) supplementation on exercise performance is equivocal. Overall, studies suggest Mg supplementation does not affect performance when serum Mg is within the range of normal values, but may improve performance when marginal or clinical Mg deficiency is present.