There is a banned substance list that comes out every year. As many athletes in the world of competitive sport know, it's not hard to figure out how to get around the rules.
The drugs listed in the conference actually made me laugh as it seems to say the kids that skate may be ones to have concentration problems or hyperactive problems, or are at least are in some way medicated including self medicated, NOT for performance reasons.
Everything is about parts per million and how fast things can clear the blood stream or at least be under IOC levels.
The show STATE OF PLAY on HBO has an episode all about the exciting world of pharmacology in sport. They's all cheaters!!!!