There are certain athletes where the consequences of being caught taking drugs, outweighs the benefits of the enhanced performances and money resulting from participating.
One such is Paula, a national heroine.
She is not stupid, what sort of a life would she have in Britain, were it ever revealed she wasn’t clean when racing?
And where would she have to go, which country in the world, could she end up in where fingers wouldn’t be pointed - what a life.
Very much the same with our latest hero, Bradley Wiggins.
I saw him being interviewed with his toddler bouncing on his knee. “How could I look him in the face in the future should I ever be outed as a drug cheat?”
And I believe him.
Similarly, but even more critical for the sport, would be the situation were Bolt ever caught taking drugs.
The sport of athletics would take years to recover from the resulting scandal, if it ever did - and Bolt (and family) would have to leave his beloved Jamaica forever.
Would he ever take that sort of gamble?