According to this guy you do alot of running in an industrial freezer:
ICE-COOL Will Knight is preparing to run his first marathon – around the North Pole with temperatures plummeting to 30 below freezing….
Will has been in training, which includes standing inside industrial freezers for up to 20 minutes – but no amount of running can prepare him for the terrain and the temperatures he will face, which drop to dangerously cold conditions. He will wear three thermal layers as well as trail shoes or even special snow shoes if the ice cap is badly rutted, as well as a balaclava, hat and goggles.
Link.