You're quitting as Blue Peter's, all-action Have-A-Go Gethin. Any regrets?

Millions. I've had the best three-and-a-half years of my life. But I'm 30 and it's time to let another lucky guy step into my shoes.

Shouldn't it be trainers?

You could say that. So far I've trained for three-and- a-half months to do a 30-mile yomp with the Royal Marine Commandos, fought as a samurai warrior in Japan and conquered my fear of horses to ride at up to 40 miles an hour. I've also built myself up to compete in a weightlifting championship and trained with the Welsh rugby team.

Always been gung-ho?

If you put me on a rollercoaster, I cry like a girl. If you make me jump out of a plane, I'll go as white as a sheet. When I flew with the Red Arrows, I threw up. For me the challenge is to have a go.

You've had some scary injuries. More like Black and Blue Peter?

You're right. I've popped my shoulder, broken a finger, and injured a leg and ankle.

Lots of time off to recover?

None. After the commando yomp, I literally couldn't move a muscle. The next day I had to drive to Battersea Park, South London, where I was dressed as a mermaid with someone spraying me with freezing water. Don't ask.

You must be amazingly fit.

Recent tests put me in the top 1 per cent of the population.

Are you pumped up now?

In the past three years my body shape and weight have changed according to the different challenges. I put on a stone for the weightlifting championships and lost one when I was in BBC One's Strictly Come Dancing.

Ever fancy yourself as a cha-cha-cha supremo?

No. Before the show I was a numpty with two left feet. But after four months of applying myself and listening to Camilla Dallerup, my partner, I started to enjoy it. I was gutted when I was voted off in the semi-final. Did all those sequins help you to get in touch with your feminine side?

I'm not sure I have one of those, but there were some surreal moments when the rugby player Kenny Logan and I would watch a bit of sport on Saturday afternoon and then start talking about the clothes we'd be wearing later. Then we'd hope no one had heard the conversation and go back to talking about rugby.

Weren't you nearly a professional player yourself?

I was offered trials by Sale RFC and have often wondered how life would have been if I'd pursued that option. I'm still passionate about the game.

You are also a talented piano player and violinist. Why such an over-achiever?

Boredom.

Hyperactive as a child?

I always wanted to know what we were doing next. I'm the same as an adult. There's also something in me that knows that even if I can't be the best, I'm going to try to be. That applies to whatever task, music, rugby or being a Blue Peter presenter.

Ever considered the catwalk?

I have done a bit of modelling. But I don't think I could stay interested in that kind of thing for too long.

Pick up any beauty tips?

Dermalogica products. I particularly like the facewash and moisturiser.

Are you happy being a metrosexual male?

I'm pretty secure about my sexuality. I'm not into fake tan or shaving my legs, but I see a link between looking good, feeling good and performing well.

You were born in Cardiff. Proud to be Welsh?

It's part of who I am. I was raised in Wales, went to Welsh-speaking school and Welsh is my first language. I'm Gethin, my dad is Goronwy and my sister is Mererid. You can't get more Welsh than that and I'm very proud of it.

You're dating the Welsh mezzo-soprano Katherine Jenkins. Are you doing that for patriotic reasons too?

Ooh, I know where this line of questioning is heading. I'm not talking about Katherine.

Relationships must be hard with the amount of travelling you have to do?

In the past three years I've visited 17 countries. But it has been worth the jet lag and the absences for the experiences I've had. I've rescued alligators in the wild, survived the Bolivian jungle, escaped a leopard. I've also been to China recently where I trained in the martial art techniques of the Buddhist Shaolin monks.

Converted to chanting and burning incense sticks?

Being Welsh, chapel and church was a big part of my life.

What about alternative medicine?

I strengthen my immune system with big doses of vitamin C and echinacea. If I were really ill, it would be the doctor.

What's next?

I still have a couple of months on Blue Peter and I have just signed to fill in for Eamonn Holmes this summer on his Saturday morning Radio 5 Live show.

Not putting your feet up, then?

No, it isn't in my nature.

Blue Peter is on BBC One Tuesday and Wednesday, 4.35pm

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