I've just swum the length of the Thames. I feel quite tired.

When you are doing endurance swimming you just need to take in as many carbs as possible to put on as much weight as you can. Basically you can eat whatever you want, which can be quite fun. Everything is guilt-free.

I haven't traditionally been a family entertainer.

I've done panel shows, which I enjoy, and on those you're recording half-an-hour of TV and sometimes they film for two hours. But with 'Britain's Got Talent,' you're on camera for eight hours, with a large theatre audience watching - and in between you're being filmed for ITV2 as you eat your lunch.

It can be difficult to be subtle and not cartoony in prosthetics. But when you see characters like Bubbles and Desiree from 'Little Britain' on screen, it makes all the hard work worth it. It's such fun watching those transformations.

I don't have a fear factor. Well, not much of one. And I'm willing to risk quite a lot - as a comedian, you're always risking a lot. You're risking failure, especially if you're improvising and going on TV shows trying to make comedy out of thin air. That is quite a risky business.

I think most people that do comedy write for themselves. I don't think there is any other way you can do it, really. Otherwise it would be quite cynical.