The athlete's responsibility for his own health

Lately I’ve been thinking a lot about how much responsibility an athlete really has for their own health. A guy I train with recently told me he was researching different performance-enhancing options online. He even mentioned seeing pages where you can buy anavar 25mg and similar products pretty easily. What struck me wasn’t the product itself, but how casual the whole thing sounded. He said, “If it’s available and other athletes use it, why not?” That got me wondering — is it fully on the athlete to understand the risks, or should coaches, sellers, and even the industry carry part of that responsibility? Where do you guys stand on this?