Don’t bother dosing uo on Vitamin C before exercising. Researchers at Colorado State University who tested mega-doses of vitamin C in hopes of proving that it could improve exercise performance discovered that the vitamin had no effect at all. The study, pulished in the Journal of Applied Physiology, aimed to link huge doses of Vitamin C – 500 milligrams daily plus intravenous infusion – with inceased breathing capacity and heart output. But neither older nor younger participants benefited as hoped, though the vitamin did reduce chemical damage to cells from oxidative stress. The researchers speculate that taking supplements may benefit only people lacking in normal levels of vitamin C. If you’re already getting enough C, megadoses won’t help you at the gym.