sports drinks
Beet juice has a small effect on athletes. "But the difference between not making the podium at the Olympics and standing on the top step is often only a couple percent," says Andrew Coggan of Washington University in St. Louis. Alastair Bland for NPR hide caption
Performance nutrition experts recommend stopping at all the hydration stations for a quick fill-up of a sports drink to replenish the glycogen that's being burned during a marathon. iStockphoto hide caption