But two Queenstown men, who will race against competitors from 16 other countries in the 2009 North Pole marathon, seem to be taking the daunting experience in their stride.
Mike Davies (41) and race partner Willy Roberts (44) entered the race about six months ago, after a late-night conversation at an Arrowtown bar.
Mr Davies had just come back from the China marathon.
"He said, `I've got this new one, the North Pole', which immediately appealed to me," Mr Roberts said.
Between 30 and 35 teams are expected to take part.
Mr Roberts, a seasoned multisport racer who is also a sailor, said the pair hoped to finish the course an hour faster than previous winners' times of about four and a-half hours.
The 42km course comprises a 4.2km loop track the pair will run together.
After each lap, they must enter the medical tent for checkups before setting out again.
"You can dehydrate really quickly, so every lap you're checked out," Mr Davies said.
Hydration would be difficult to manage in the excruciating cold, Mr Roberts said.
"Sweating is one of the biggest issues in this. "That's what worries me the most - getting enough clothes on to get warm. But as you go . . . you're going to be sweating. If you get wet, it's difficult to keep warm."
Every competitor must have their skin fully protected.
Clothing would include a full balaclava, goggles, gloves and mittens, longjohns, waterproof running pants and several layers of thermal clothing under a "shell".
Mr Davies said their running shoes would need to be about two sizes bigger to allow for the two or three pairs of socks they would be wearing.
However, there was a chance they might also run in snow shoes, Mr Roberts said.
"We may end up starting in snow shoes and then go into running shoes as the snow compacts."
Neither man is a stranger to long-distance events.
Mr Davies, who has completed the Great Wall of China marathon, the New York marathon and the Kepler, said he tried to do "one odd one" every year.
Mr Roberts recently competed in the Coast to Coast as a "tune up" and the Longest Day.
Short of setting up a treadmill in a deep freeze, there was little the pair could do to fully prepare for the temperatures they were going to encounter and, with little time in Oslo to acclimatise, it would be "an interesting challenge", Mr Roberts said.
"We need to do as much homework as we can."
Part of that would see them running on glaciers this weekend to try out their footwear and get a taste of what is to come.
However, one of the biggest unknowns for the pair was the mountain-bike ride, which was an additional event this year.
While the pair had only intended to enter the marathon, the organisers gave all marathon competitors free entry to the 100km bike section.
The pair will leave Queenstown on April 1 and start the marathon on April 7.
