We investigated whether endurance exercise might modify the blood antioxidant status and lipid profile after omega-3 fatty acid supplementation. Two groups of healthy, fit males performed 1 h of exercise with a constant work load corresponding to 60% of their individual VO(2max) and various pedaling rates (45 min-60 rev/min followed by a maximal rate), before and after receiving, over 6 weeks, omega-3 fatty acids in a daily dose of 1.3 g or placebo. The resting concentration of triglycerides decreased after omega-3 fatty acid consumption.

In response to endurance exercise, the superoxide dismutase activity markedly decreased in sedentary control subjects.

This effect was partially protected by omega-3 fatty acid consumption. Supplementation tended to increase atalase activity in response to exercise, and this activity was significantly higher after 1 h of recovery.

We conclude that the beneficial effect of omega-3 fatty acid supplementation during endurance exercise may be due to the activation of the superoxide dismutase and catalase pathways.

Key Words: Exercise, Omega-3 Fatty Acids, PUFA