In reply to The Ivanator:
> It does illustrate that when certain individuals become obsessed by a specific goal they are sometimes prepared to go to any lengths to achieve it.
I think that's always been true and always will be. People will always try to push physical boundaries beyond their natural limits. Some activities really seem obvious ones for drugs to help, but without being in the 'steriod' category most people thing of when the topic of drug cheat's is mentioned.
Your example of high alititude adapration is one.
Free-divers are another one, the champion free divers hold their breath for around 5 minutes...that's silly, I don't know, but I'm sure certain drugs could help here.
Golfers. Someting to calm their nerves so that they're relaxed before the big shot.
There are probably a load of others.