LONDON, (Reuters) – Olympic and world sprint champion  Usain Bolt believes the tainted image athletics has acquired  after several high-profile drugs cases in the past few years  will clear as time goes by.

“It’ll take a couple of years for people to start believing  that we are actually clean. Then this tainted image will go  away,” the 22-year-old Jamaican told a news conference at the  launch of the Zeitz Foundation yesterday.

“As soon as someone starts running fast there’s always a  problem, but I’ll continue running fast. I’m clean without a  doubt.”

In the past decade American sprinters Marion Jones, Tim  Montgomery, Justin Gatlin amd Kelli White plus Briton Dwain  Chambers have been banned for doping offences.
Last month four of Bolt’s compatriots were banned for three  months after being found guilty of using the banned stimulant  methylxanthine.

However, Bolt said he felt the International Association of  Athletics Federations (IAAF), together with the World  Anti-Doping Agency (WADA), were showing the way.
“People are always saying things, but it’s changing because  the IAAF are doing a very good job cleaning up the sport.”

Former 110 metre hurdles world champion Colin Jackson,  speaking alongside Bolt as an ambassador for the foundation  which was launched by Puma chief executive Jochen Zeitz, paid  tribute to the lanky Jamaican’s effect on athletics since he  stormed to triple Olympic gold last year.

“There’s a lot of hope he’s going to carry our sport forward  because it’s been dark for many years,” the 43-year-old Briton told Reuters.

“It’s so good to have someone so fresh, so exciting and who appeals to so many people.
“He’s taken on all the responsibilities really well. For me he’s just got to keep on doing exactly what he’s been doing.
Don’t change the magic formula.”
Bolt was scheduled to fly to Africa later on Thursday with  Jackson and Zeitz.
“Hopefully I can outrun a cheetah, but I won’t be trying that anytime soon,” Bolt told Reuters, grinning from ear to ear.

“Maybe some lions?” asked Zeitz.
“No way,” replied Bolt. “I’ve heard some bad stories about lions.”