"When I take a groups of women out into the cold environment, they are a lot more unsure, their default position is 'I can't do this,'" she said. Her job then becomes to convince them about the opposite.

With men, it's different. "Usually they'll fling themselves at it and their default position is 'I already know how to do this, I know exactly how to do this,' and it's a matter of bringing them in and telling them that they need to think more and watch out for certain things."

After days of skiing alone, in extreme cold, these differences disappear and men and women have to deal with the same issues.

Apart from one, which Aston has yet to find a solution to: Going to the toilet.

During the coldest days in Antarctica, she was deliberately dehydrating herself to avoid the need to get undressed in the bitter frost.

"It's the only time in my life I've ever ... wanted to be a man," Aston said. "You see the guys just turn around and have a quick pee in the snow and you go, 'Arrghh, I have to get undressed in this cold!'"