Why bother in the first place? Seriously.
I think it's well past time to stop pretending that there's some special purity in these competitions, "athletic" or gaming or whatever, and acknowledge them as what they are: entertainment. And the competitors are entertainers. Their job is not so much to win the race or Starcraft match, or to put the ball through the hoop or into the end zone or whatever. Their job is to put butts in stadium seats and eyeballs on the TV.
We don't drug test Lady Gaga, and take away her Grammy when she tests positive for pot. Robin Williams gets to keep his Golden Globe awards for Mork & Mindy, despite being hopped up on cocaine half the time. And we don't drug test the Rolling Stones before they go on tour and suspend Keith Richards from the first 10 shows when he tests positive for... probably just about everything.
So really... What's do special about Lance Armstrong or Barry Bonds or some Adderall-popping gamer that makes their brand of entertainment any more "pure" than any other?