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Walliams says he has a 50/50 chance of success
Little Britain star David Walliams is attempting to swim the English Channel for charity. Few people who try this succeed. Why?
"I'll just be in a pair of Speedos and goggles - it's what the public wants," says David Walliams about his attempt to swim the English Channel.
But jokes aside, what the 34-year-old comedian is attempting is quite a feat. Few people succeed - just 10% according to some figures - and the swim is known as "the Everest of open-water swimming".
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Walliams, who is raising money for Sport Relief, has spent the last 11 months training with former Olympic pentathlete Greg Whyte and hopes to complete the 21-mile charity swim in under 16 hours.
"I reckon I have a 50/50 chance of getting across. I hope people see it as a symbolic thing," he says.
There are a lot of factors that combine to make the swim hard but the cold is the biggest hurdle, says Alison Streeter, who holds the world record with 43 successful swims across the channel.
Alison Streeter first swam the channel at 18
"It's not about the distance, lots of people can swim the equivalent in a pool," she says. "It comes down to the cold. Fit swimmers are often all muscle and don't have much fat on them, this means they get cold quicker and once the cold gets into your muscles it is very hard to continue."
Walliams plans to make his attempt some time between 28 June and 15 July. This is early in the season and so means the cold will be an even greater issue, says Ms Streeter, 41.
The tides are also hard to predict as they are strong and change direction approximately every six hours. They also change in height and flow speed every day.
The wind and weather are also a problem - as the Dover Straits are prone to local weather conditions that can change very quickly and which do not match the forecasts.
There is also the problem of the number of ships using these waters - because to go from England to France you have to swim across the shipping lanes.
There are over 600 commercial ship movements and 80 to 100 ferry crossings between Dover and Calais every day - and it's the job of the accompanying pilot boat to keep the swimmer out of the path of these vessels.
As channelswimming.com says: "Put all these things together, include a large portion of mental tension, note that everything is 'approximate' or 'about' and you have the world's hardest swims."
Ms Streeter says not being able to judge what conditions you will face on the day is the challenge.
"I have done 43 swims - seven in one year once - and every one of them has been different," she says.
"David Walliams seems to be preparing in the right way, so he will have a fair chance."
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