Rio results could take years to confirm: WADA

London: The incoming director general of the World Anti-Doping Agency (WADA) has said it could be years before the results of August's Rio Olympics are upheld.

Last week saw Australian race walker Jared Tallent belatedly awarded a London 2012 Olympic gold medal after he was promoted from silver four years ago because of a Russian doping case.

"The storage of samples is a deterrent," Olivier Niggli told AFP in an interview on Monday

"You can tell people if you cheat today, because you think this is not detectable, it will be detectable tomorrow," the Swiss lawyer said.

"This has an impact on the risks athletes take because they know they can lose their reputation afterwards, " added Niggli, who will succeed long-serving New Zealander David Howman as WADA director general on July 1.

"But the other side of the coin is that you may have to re-do the (medal) classification," explained Niggli on the sidelines of the WADA media symposium in London.

"But would we better off letting cheaters get away it? Probably not. Would we rather do that quicker, probably yes, but science's pace is science's pace.

"You don't want to ruin the samples by re-testing too early," insisted Niggli, with WADA's statute of limitations on the holding of such samples currently set at 10 years.

"You may want to wait a little longer to let science progress.

"Maybe some innovative science will one day allow us to be quicker."

Friday saw the International Association of Athletics Federations (IAAF) uphold an international ban on Russia's track and field competitors first imposed in November after a WADA report revealed state-sponsored doping and mass corruption in Russian athletics.

The Russia team is now ruled out of all athletics events in Rio, although Russian athletes training outside the country can apply to compete as neutrals at the August 5-21 Games.

If the final results of Rio testing may not be known definitely for some time, Niggli said that changing Russian attitudes was also likely to be a lengthy process.

"What we are observing now is that the top (in Russia) has changed their speech and are trying to say the right things, but it doesn't go further down.

"The entourage of the athletes, the club coaches are very reluctant to accept that doping is not part of sports. It's likely to take a bit of time."