Vitamin C Inhibits Free Radical Damage in Runners

The purpose of this study was to examine the effects of pre-exercise ascorbic acid (vitamin C) supplementation on markers of lipid peroxidation, a measure of free radical damage. Participants were 14 trained runners: 7 ingested 1 gram of vitamin C prior to a 4-hour race, and the other half did not take a supplement. Blood samples were obtained prior to and following the race. Results revealed an 8.6% increase in susceptibility of low-density lipoproteins (LDL) to oxidation in the control group. However, no change was observed in individuals who received supplementation. In addition, the vitamin C also promoted a 9.9% increase in vitamin E levels, compared to no change in the control group. The authors concluded that vitamin C supplementation (1 gram) prior to intense endurance exercise inhibits the post-exercise increase in LDL susceptibility to oxidation exercise and thereby prevents this acute proatherogenic effect.