Effects of antioxidant vitamin supplementation on resistance exercise induced lipid peroxidation in trained and untrained participants

Abstract

High intensity aerobic-type exercise produces oxygen free radicals that can cause damage to lipid membranes (lipid peroxidation) that may lead to many problems such as the inactivation of cell membrane enzymes, the progression of degenerative diseases (cardiovascular disease and cancer) and lessening of the effectiveness of the immune system. Little research has examined lipid peroxidation associated with high intensity resistance exercise, nor the protective effects of antioxidant supplementation. Additionally training state, which could conceivably affect one’s ability to counter free radical damage, has not been adequately studied. Fourteen untrained participants and 13 trained participants took part in a double blind, placebo controlled crossover experimental design study. They received 885 mg tocopherol acetate/day for a 2 week period, received the placebo during another 2 week period and at the end of each period performed the Resistance Exercise Test (RET). A 2 group (trained vs untrained) x 2 treatment (vitamin E vs placebo) x 3 time (pre exercise vs immediate post exercise vs 6 hours post exercise) factorial ANOVA with repeated measures on time was performed on Malondialdehyde (MDA) values. There were no significant group or treatment effects found between the 4 groups assessed. There was only one significant difference found and that was in the main effect for time (F [2,49] = 22.41, p =0.00). This study concluded that the RET caused a significant increase in MDA in all 4 groups at 6 hours post exercise. There was no evidence that vitamin E supplementation was effective in reducing oxidative damage in comparison to the placebo group. As well, there was no difference between the trained and untrained groups with respect to their impact on lipid peroxidation measures.