If there's one word to describe Michal Kielbasinski, a Polish adventurer who's just set off on a lonely and gruelling 1,600-kilometre run through the remote back country of Yukon and Alaska, it's offered up by his friend Mike Tribes — "stubborn".

Kielbasinski is back on the trail that almost claimed his fingers and toes, two years ago — and this time he aims to finish what he started, and then some.

Michal Kielbasinski

Kielbasinski in Whitehorse hospital in 2015, with severe frostbite. It wasn't certain that all his digits would be saved, but they were. (Facebook)

Kielbasinski set off in 2015 to compete in the Yukon Arctic Ultra, a long-distance race from Whitehorse to Dawson City, Yukon. But less than a day into that race, the –40 C temperatures sent him to hospital with severe frostbite.

He nearly lost some digits, but doctors were able to treat his injuries so he's now got "pretty much full use of them again," according to Tribes, who helped Kielbasinski set off from Whitehorse and will provide his support along part of the way.

Now, Kielbasinski is determined not to fail a second time.

"It just seemed like something that he wanted to do, to be able to run that distance. And he felt quite defeated by not being able to make it," said Tribes. "He's pretty stubborn and he just wants to do this."

Raising money for dogs

Kielbasinski is not racing this year, though. He's doing it on his own, at his own pace.

But he is following the same route — using the Yukon Quest sled dog trail — and he plans to go past Dawson City, and continue all the way to Fairbanks, Alaska. He's equipped with a GPS unit to track his progress online.

Kielbasinski is also raising money this time, for homeless dog shelters in Poland.

"He just felt that he wanted to do something for the dogs," Tribes said. "And because the [Yukon] Quest trail is what he's using, he was kind of inspired by that."

Michal Kielbasinski

Kielbasinski reached the Yukon community of Braeburn on Thursday morning. He's raising money for homeless dogs in Poland. (Mike Tribes)

With files from Cheryl Kawaja