31/01/2012 17:38 GMT | Updated 04/05/2012 11:25 BST

Biking, Skiing and Kiting Across Antarctica for Sport Relief

A lot of people told me it couldn't be done, but when asked if I'd travel across Antarctica by bike, ski and kite to reach the South Pole for Sport Relief, I knew it was a chance I couldn't turn down.

I know people thought we were mad for bringing a bike, but I hope it's something the Blue Peter audience can relate to. Lots of them have bikes and know what it's like to ride them. I didn't know how to kite ski, I don't really camp and I've never cross-country skied, so I definitely jumped in at the deep end, but I guess I am naive and I think that's a good thing, otherwise I probably never would have agreed to do this!

Now, 500 miles and 18 days later, here I am, standing at the bottom of the world at the southernmost point with a massive smile on my face. I keep grinning because I can't really believe I'm here, it's just so beautiful staring out across the frozen desert with the sun shining down making the snow sparkle in the light. I'd pinch myself if my heavily padded mittens permitted it!

To finish in the same week as Scott's anniversary is an honour. I am patriotic because our history is peppered with great characters like Robert Falcon Scott and being here 100 years after he made it to the Pole really does give you goose bumps. I heard that King Edward said every little boy in the land should be made to read the story of Scott of the Antarctic to inspire the adventuring spirit upon which the empire is built. I almost whole heartedly agree with that today, the only thing I would say is that every little boy and every little girl should be made to read the story.

I didn't come here to prove I am a polar explorer or that I can ride a bike in Antarctica. I came here to show you that you never know what you might be able to achieve if you try. If people doubt you, who cares? Just get your head down and get on with it.

Don't get me wrong, this has been one of the hardest things I've ever had to do. The climate is so inhospitable that it's like a constant battle with the elements. I've experienced temperatures as low as -48°C and the cold makes it almost impossible to do the most basic of things, like going to the toilet or keeping hydrated. It's so cold in the day you feel you are certain to get black fingers if you take off your gloves to unscrew a water bottle. It's mad. You can feel perfectly fine, but as soon as you stop your hands and face go from cold, to painful, to agony. If you don't sort it out you can have frostbite in minutes.

Aside from cold hands, quite often my water bottle freezes so I pretty much gave up drinking during the day which led to some serious dehydration problems. Some days we've been exercising pretty much non-stop for nine hours and it's not exactly easy to stop to eat or rehydrate. I've lost over two inches from my waist, which means now we've finished I really need to try and pile on the calories.

I've suffered blisters from day one and have so far gone through 16 metres of medical tape. I've lost toenails and it's been agony, but I was determined not to let my feet stop me from reaching the Pole! The other concern has been my chesty cough - the freezing air I'm breathing has affected my lungs and the paramedics warned that if I didn't take it easier I could develop pneumonia. This was a really scary thought and I had to try and slow down, despite my eagerness to reach the Pole.

Of course I have missed home, my friends, family and basic luxuries but it's made me appreciate them even more and even though it's been tough - I've never wished away a day in Antarctica. The thing that makes these trips for me are the people, I've been surrounded by a fabulous crew and I will be eternally grateful to them for making me laugh when there's been times I've been so cold I've wanted to cry.

When it got really tough I thought about the people I've met at projects which will be helped by Sport Relief money. I've met children in Sierra Leone who no longer sleep on the streets thanks to an amazing project. That's why I can't complain about any part of this because it's nothing compared to what some people go through every day of their lives. I did this in the hope it would inspire people to take part in Sport Relief and raise money for projects like the ones I've seen. I really hope as many people as possible do.

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