by Edmund R. Burke, Ph.D.
The purpose of this study was to examine whether vitamin E supplementation in athletes would attenuate an increase of serum enzymes as an indirect marker of muscle damage following a sudden large increase in the running distance in 6 days of running training.
A randomized and placebo-controlled study was carried out on fourteen male runners who were supplied vitamin E (1200 IU/day) or placebo for 4 weeks prior to and during 6 successive days of running training (48 km/day). Resting venous blood samples were obtained before training, several days during the training days and three weeks after the running training. Blood levels of vitamin E, measures of free radical damage and markers of muscle damage were quantitatively analyzed.
Vitamin E supplementation significantly increased blood vitamin E levels and decreased free radical production compared with pre-supplementation levels. Although blood markers of muscle damage activities increased significantly at the end of training in both groups, significantly lower levels were observed in the vitamin E group compared with the placebo group.
These results indicate that vitamin E supplementation can reduce the leakage of enzymes showing muscle damage following 6 successive days of endurance running. The protective effect of vitamin E against free radicals probably inhibits free-radical-induced muscle damage caused by a sudden large increase in the running distance.