The beach volleyball competition brings a touch of southern California to Horse Guards Parade. But there's more to the sport than the spectacle of toned bodies in swimwear. It is a highly athletic and absorbingly tactical sport. Matches are the best of five sets, the first four to 21 points and the final one (if required) to 15. As in the indoor version, points can only be scored by the team serving - if they lose a rally, service passes to their opponents. But there are two rather than six athletes per team, and the court is covered in sand to a leg-sapping depth of 40cm. Johnny Acton
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