Go ask Lance Armstrong and the entire sport of competitive cycling. Go ask Barry Bonds, Sammy Sosa, Mark McGwire, or Roger Clemens. Not only has the legitimacy of these athletes been questioned, they have encouraged cheating so much that it has become the ONLY way to win.
No one believes any rider in the Tour de France is clean. No one believe you can hit 60 HRs in a season without PEDs.
Thanks a lot cheaters. Not only have you ruined your careers, you have ruined your sports forever.
Here is a link to LIFE magazines Tour de France photos from when it was a clean sport: