You're the creator of the children's hit TV show LazyTown, and your alter ego Sportacus is famous for fighting childhood obesity. How do you keep fit?

I believe that you can train by integrating fitness into your daily life. So every time I board a plane, I do 200 push-ups before I get on. I map out my life with exercises. I cannot go into a shower, for example, without previously having done 20 squat jumps.

Have you always been this sporty?

When I was 5 I became a professional running telegram. Not everyone had phones in the tiny Icelandic town in which I grew up, so I would take messages from house to house, running 6km (3 miles) maybe nine times a day.

How did you make a career of it?

When I was young, a friend and I picked a sport for each other. We bet one another that we could not be world champion in three years. He picked competitive aerobics for me and I picked snooker for him. I became the world silver medallist and he went to Blackpool to learn snooker and ended up becoming the boyfriend of Mel B of the Spice Girls.

You must be amazingly driven.

Not really. In competitive aerobics you have two minutes to show how good you are. The more you can pack into each movement, the more points you get. So I just try to pack in movements all the time.

Have you ever been injured?

Yes; four times. The worst was in 1995 when I premiered LazyTown on stage. I rented a local theatre, I financed it, I wrote it and directed it. I did a high jump at the dress rehearsal and broke my arm. The make-up woman was doing my Sportacus make-up while the doctor was numbing my arm so that I could do the show. Every time I did a handstand, I could feel it only on one arm. For weeks after, I took the cast off every weekend to do the show.

Ouch. So you've got the pain threshold of a superhero?

No. I am like every man. We always whinge about pain.

Have you ever been overweight?

Never. My weight never deviates from 70-75kg (11st-11 1/2st). But then my fitness is not normal. I don't do any formal training.

So you always stick to the advice on LazyTown to eat plenty of fruit and veg?

A healthy person is someone who is in balance. Have a burger, but also have salad. Do sports, but also relax a little. I've always been this way.

It doesn't sound as if you relax much...

I know. When I was setting up LazyTown on TV I worked from 7am to 2am, six days a week. For four years. But I didn't look on it as work.

What's the highest number of jumps you have done at once?

Five thousand. It was fun, although I had to try to do it without sweating to stop my painted-on moustache from melting.

You sound too good to be true; no vices?

I don't smoke. I've never taken drugs. I don't even take vitamins. I may have a tiny bit of white wine with fish, but I've never tasted beer and I've never been drunk. I think I was afraid that if I started I might overdo things.

Green tea or GP?

If I have a headache, I go for a steam bath. Steam baths are my pharmacy. Sometimes I'm in them for two hours. I have a computer outside and go in and out answering e-mails. I'm Icelandic, remember.

Does that mean you're in financial meltdown?

Iceland is in financial trouble, but I am one of the lucky ones because I have a concept that I have sold to 100 countries.

You must feel blessed.

If I lost all my money, I would still feel rich because I am doing something I love.

What's your top fitness tip for children?

Children should exercise through play. After the age of 7, they should try as much as they can. Next month I am launching LazyTown Fitkid, which will be fun fitness classes, incorporating Sportacus-style training and dance classes.

What about for us lazy adults?

Look at your day, your life, your week. Are you moving enough? Why not do lunges with the shopping bags? Why not walk backwards through the shop? Remember how you used to play as a kid and try to bring that back into your life.

INTERVIEW: ROSIE MILLARD

LazyTown Live! The Pirate Adventure is touring nationwide from January 29; lazytownlive.co.uk . Find out more about LazyTown FitKid Clubs at fitkid.co.uk or call 08700 851000

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