A competitor in this year's Yukon Arctic Ultra is now fighting to save his fingers.

Michal Kielbasinski is recovering in hospital after he suffered severe frostbite during the race because of extreme cold weather. He was attempting to run 700 kilometres from Whitehorse to Dawson City.

Just one day into the race, the 46-year old Polish competitor was forced to withdraw due to frostbite on his hands, arms and legs.

"I decided just to stop the race and try to save what is possible," he says.

"This was the first time in my life I was in such low temperatures," says Kielbasinski. He says he's raced in -25, but temperatures on the first day of the Yukon race were closer to -40. "It's a huge difference," he says.

Kielbasinski, who was leading the Ultra's longest distance running event when he withdrew, says the experience has been painful and doctors are still working to save his fingers.

Trevor Mead Robbins is a friend who lives in Whitehorse. "Right now it's just cross your fingers and wait and see," he says. "The good news is that the race officials medevaced him by helicopter, they didn't waste anytime there so instead of a couple of hours to get back it was a 20 minute trip once he was picked up."

Race organizer Robert Pollhammer says the situation is very unusual.

"Well I think it's safe to say that in 13 years of running this race this is probably the worst we had," says Pollhammer.

He says frostbite does happen, but not usually to this extent. "We get superficial frostbite, something that would be like a bad sunburn but it's not like that in every race people actually end up in hospital."

Pollhammer says Kielbasinski is a seasoned adventure racer. "I think what happened, basically, is that he thought he could out-run his problem and he didn't stop and deal with the problem and when he came to a check point he did not follow our advice to stop and warm up."

Temperatures on the Arctic Ultra course this year have dipped to -45.