Resveratrol antioxidant hinders training benefits
Resveratrol, an antioxidant found in grape skins, has acquired a reputation over the past decade as an anti-aging substance that offers the benefits of “exercise in a pill.” In rodents, it seems to work like a charm. But when researchers at the University of Copenhagen tried it with humans, they found surprising results. They put 27 older men through an intense eight-week exercise program, while giving 14 of them a high dose of resveratrol and the rest a placebo. The exercise program worked in the placebo group, producing significant improvements in aerobic fitness, blood pressure and cholesterol – but these benefits were suppressed in the group taking resveratrol.
This isn’t the first time antioxidants have been found to interfere with training benefits. Back in 2008, a study found that a gram per day of vitamin C blocked the increase in endurance- boosting mitonchondria from training, and subsequent studies have found similar results. Scientists now believe that the “reactive oxygen species” that are targeted by antioxidants serve as crucial cellular signals telling the body to adapt to the stress of training – so if you have too many antioxidants, your body doesn’t get the message. It’s not that resveratrol and other antioxidants are bad – it’s just that the megadoses found in some supplements are far greater than you find in foods, which can throw off this delicate balance.
– Alex Hutchinson