Last updated at 07:40

David Walliams joins SwimBritain relay

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The Gangsta Granny writer, David Walliams, who swam the length of the River Thames for Sport Relief, has joined school kids from across the UK to take part in a special swimming relay.

It's all to get more people into swimming and BBC Sport's Mike Bushell donned his cap and armbands to have a go too at London's Aquatics Centre.