Carl Lewis: Athletes know drug cheats

Lewis, a nine-time Games gold medallist, was given gold after the 100m final at Seoul 1988 following Ben Johnson's positive test.

The American said athletes were aware of rivals who were taking drugs, but complications meant no-one was willing to speak.

"The reality is, it's a very complicated issue and its people. I think a lot of times we're going about it the wrong way," Lewis said.

"We're teaching kids at a young age you are getting rewards for really not doing anything, so that's part of it.

"I think when you get up to the professional level, now, athletes understand. They know who's taking drugs but they are not willing to speak out about it. It's a very complicated issue. It's more than I just want to run fast and win and make money. It's an issue that you have personally.

"There is a self-esteem issue if someone takes drugs. There's something there because why would you cheat? So I think we should look into the social issue.

"We should look into, the psychological issue, with the individuals, but we don't go deep. We just scratch the surface."