May 25, 2004 -- A combination of moderate exercise and antioxidant vitamin supplements may work together to help protect against hardening of the arteries, a condition known as atherosclerosis, a new study suggests.
Strenuous exercise can increase the dangers of this condition by increasing free radicals (unstable molecules that damage cells) and promoting inflammation in plaques, causing them to become unstable, loosen, and enter the bloodstream.
However, researchers say a graduated program of moderate exercise appears to have a protective effect. In addition, antioxidant supplements, such as vitamin E and vitamin C, may add to these effects by helping to scavenge and reduce free radicals.
The results appear in the current issue of the Proceedings of the National Academy of Sciences.
Exercise Plus Antioxidants Protects Arteries
Half of the mice participated in exercise training that consisted of graduated swimming and the other half remained sedentary.
After 18 weeks, researchers found the mice that had exercise training had less evidence of atherosclerosis than the sedentary mice.
This protective effect was enhanced when researchers added vitamin-fortified water containing vitamins C and E and the amino acid L-arginine to the mice's diets. L-arginine is not an antioxidant, but it can reduce sensitivity to free radical damage.
Researchers say the findings suggest that moderate exercise and antioxidant supplementation may work together to promote artery health and prevent the development of atherosclerosis.
A moderate degree of exercise is based on a maximal heart rate attained during physical activity of 55%-60%.
"Thus, to achieve truly beneficial effects the focus of attention needs to be on the right degree of exercise (graduated and moderate) and the ideal mixture of supplements (vitamin E together with vitamin C and L-arginine)," write researcher Claudio Napoli of the University of Naples, in Italy, and colleagues.
SOURCES: Napoli, C. Proceedings of the National Academy of Sciences, online early edition, May 24, 2004.