Sprint superstar Usain Bolt says "stronger bans" are needed to help clean sport from the stain of doping.
"I have always said you need to put in stronger bans: Only one chance," he told dpa ahead of the London premiere of the film "I Am Bolt."
"You have to try and interfere in people and tell them: 'listen to me, you gonna get caught, and we are not gonna give you another chance'."
Some big names in sport including several Premier League soccer stars, athletics Olympic champion Mo Farah and former tennis ace Boris Becker were in attendance at Leicester Square on Monday evening for the film about the career and legacy of the nine-time Olympic gold medallist.
Asked why he wanted to show his struggles and fears in the film, the 30-year-old Jamaican said: "I want them to know me. Most people always say, 'oh you make it look so easy.' And I say, 'no, it is not'."
Bolt plans to retire from athletics after the world championships in London next year.
