Don't hold your breath if you're expecting to spot four-times Olympic swimming champion Alexander Popov in a pool any time soon.

As one of the greatest sprint swimmers of all time, one would have expected Popov to take a recreational dip from time to time after he retired from the sport almost two years ago.

But even though Popov has maintained his lean two-metre tall frame, the Russian made a surprising admission.

"I go into a pool once every six months," Popov, the 50m and 100m freestyle champion from the 1992 and 1996 Olympics, told Reuters.

"I spent 25 years in a pool in chlorinated water and have probably (done enough) swimming to go around the earth once if not more. So I don't have any urge to get into a pool these days."

Popov, who was in London to back the 2014 Winter Olympics bid of Russia's Black Sea resort of Sochi this week, said his own experience had put him off encouraging his two young sons to follow in his footsteps.

"No, I don't want them to become professional athletes," Popov, who turns 35 next month, said as he shook his head from side to side.

"I'd prefer them to do other things. It's so difficult to get to the top. The standards are so high. Lifestyle has changed. The world has opened up to them as they have computers."