Exercise helps my back. If I don't exercise, that's when it starts to hurt. The pain is a good motivator to run and exercise.

I exercise about 40 minutes a day, and I'll run one day and do circuit training the next day. I live in an area where there are brilliant hills and mountains, so I get a good hill run with my dog. At home, I'll do the circuit training with old weights, along with pull-ups in the trees and that sort of stuff.

One killer exercise that's really great is pull-ups with your legs out level. That's my favourite. It's such functional core strength, and that's why I can climb up trees and down vines.

Accidents on big mountains happen when people's ambitions cloud their good judgment. Good climbing is about climbing with heart and with instinct, not ambition and pride.

I find skydiving really hard. I broke my back while skydiving when I was in the military, and for 18 months all my nightmares were about falling.

I don't like expeditions where it is a total lottery whether you live or die. You have to keep those sort of good luck cards for rare occasions!