![](http://www.menshealth.com/sites/default/files/2014/01/caffeine%20run.jpg)
In most of sports’ recent doping scandals, there’s one thing no one questions: the substances used. But next month—on sports’ biggest stage—one known performance-enhancing drug will be allowed. In fact, you may have used it to boost your own performance as recently as this morning.
Read the full article in Men’s Health.