British sprinter Dwain Chambers has warned athletes over the dangers of performance-enhancing drugs ahead of this summer's Olympic Games.

The 34-year-old, who was banned from 2003 to 2005, was recently cleared to compete in London after the British Olympic Association lifted their policy of lifetime bans for drugs cheats.

"I hope my presence makes people think twice and not do it," he told The Times. "I hope they never contemplate it because it really doesn't help.

"You may look at times and statistics but it doesn't help your life. It ruins your life and you will regret it for ever.

"I hope I can be used as an example. Living the lie eats you up so you can't get away with it even if you don't get caught."

Chambers's world junior championships 100m record was broken by 19-year-old Brit Adam Gemili in Barcelona on Wednesday night.