There is a tense and slightly jaded look about Asafa Powell which tells you he knows the question is coming. So we joke about the weather, why the Jamaican fondness for Guinness has really brought him to Ireland and then move on to the harder stuff.

The former 100 metres world record holder and three-time Olympic finalist knows that somehow his credibility will always be questioned: no athlete can test positive, no matter how minor the offence, and walk away unscathed.

For the 32-year-old that moment came in July 2013, when news broke that a drug test, taken after the Jamaican championships, revealed traces of the banned stimulant oxilofrine. He wasn't the only one – fellow Jamaican and training partner Sherone Simpson also tested positive for the same substance.

On trial

No man runs 9.72 seconds for the 100m on oxilofrine alone. However, the credibility of top-end sprinting was once again on trial. It didn’t help Powell’s cause that his case coincided with the news that American sprinter

Tyson Gay

had also tested positive for precursors of testosterone.

“It’s been very hard to forget about it, because everywhere you go it’s the first thing people want to talk about,” says Powell. “So yeah, it’s hard to put it behind you. But right now I’m focused on the future, trying to run fast times again.”

Indeed Powell was back on the track just over a year later. The Jamaican athletics federation – having been derided for their allegedly soft stance on drug testing – slapped him and Simpson with an 18-month ban. Powell, however, traced the positive test for oxilofrine to a new food supplement he had added to his training regime – the dubiously named Epiphany D1.

He appealed to the Court of Arbitration for Sport, which doesn't normally reduce suspensions, yet they upheld his appeal (and also Simpson's) and reduced the ban to six months. Powell then raced several top meetings towards the end of last summer, running 9.87 seconds – the third fastest of 2014 – behind the former two-time doping offender Justin Gatlin, who ran 9.77.

Each case can only be taken on its own merits, and for Powell that also means highlighting the dangers of playing around with any food supplement, unknown or otherwise.

“What I can say is that if happens to Asafa Powell it can definitely happen to anyone, so athletes have to be very careful about what they put in their body,” he says.

“Of course, the safest thing is to say take nothing. But you do need to be very careful about everything you put in your body, make sure it’s properly tested. It’s ridiculous what you have to do to be very safe in this sport.”

Racing indoors isn’t normally part of Powell’s season, but with a World Championships in Beijing on the horizon later this summer, and the Rio Olympics not far beyond that, he’s clearly come to Athlone keen to make up for whatever time he lost during his ban. He runs the 60m this evening, and should win easily while looking to improve his indoor best of 6.50 seconds.

World record

His 100m best of 9.72 seconds goes back to 2008, the same year his previous world record of 9.74 was bettered by fellow Jamaican Usain Bolt, then taken down to 9.58, in Berlin in 2009. He feels both men can run quicker again – although there’s still only one man to beat.

“I don’t think I’m past my best, and definitely feel I can run as fast again, if I keep doing the same things I was doing at 21. I still feel strong. But of course, Usain is definitely still the man to beat,” says Powell.

Also on show in Athlone this evening is the fastest woman alive in the American Carmelita Jeter, who ran 10.64 back in 2009, that time only bettered by the late Florence Griffith Joyner, with her 1988 world record of 10.49. At 35, Jeter may also be a little past her best, but she hasn't given up on running closer to 10.49. "I think that record will someday be broken," she says. "They said the 4x100m could never be broken, and we broke that, with our 40.82 [at the London Olympics]. "

A little more likely to break a world record – perhaps even in Athlone this evening – is Mutaz Barshim (23) from Qatar, who is closing in fast on Cuba’s Javier Sotomayor’s 22-year-old world record of 2.45m. Barshim jumped 2:43 last summer.

“It’s just patience, hard work, and dedication,” he says. “The world record might happen soon, or might never happen. Anything is possible.”