Free radicals are unstable and tend to react with the fats within the cell membrane.
Its effectiveness has been demonstrated in aerobic exercises like running, but has not been adequately tested with anaerobic training, such as weight lifting. Eleven college-age male subjects were given 1200 IU of vitamin E or placebo capsules daily for 3 weeks. On day 21, the subjects exercised by lifting weights, and 45 minutes later were given a second glucose drink, followed by a re-testing of their muscle power. Results of the study showed that vitamin E significantly reduced the blood levels of creatine kinase, which is an enzyme marker of membrane damage. Vitamin E intake also reduced the formation of malondialdehyde, a blood marker of free radical formation.