Athletes who try to beat drug tests by micro-dosing risk ruining their reputations in the future, a leading UK Anti-Doping official said on Thursday.

The practice of micro-dosing, in which athletes administer repeated small doses of prohibited substances that do not show up under most current testing procedures, has been put in the spotlight by allegations made against Olympic champion Mo Farah's coach Alberto Salazar this week.

Micro-dosing is one of the unethical practices in which it is alleged Salazar indulged at his headquarters in Oregon, according to a BBC Panorama documentary broadcast on Wednesday.

Salazar has protested his innocence, with officials remaining confident retrospective testing will eventually expose drug cheats to the world.

UK Anti-Doping's head of science and medicine, Nick Wojek, said: "We have the ability to store samples for up to 10 years so if new techniques become available to test for prohibited substances, we can sanction athletes we were not able to catch in real time.

"That is the objective - to use research grants to develop tests so that if we are not catching them now we have got a greater chance in five to 10 years' time.

"Hopefully that helps provide the deterrent that if you are doping now and we've got your sample, you are not in the clear."

There is no suggestion Farah has broken any rules and the Olympic 5,000m and 10,000m champion told the BBC: "I have not taken any banned substances and Alberto has never suggested that I take a banned substance."

Some of the allegations centre on Farah's training partner Galen Rupp, who finished second behind the Briton in the 10,000m final at the 2012 Olympics in London.
Source: AFP