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While her sister attended Derby Day in Epsom, England with Queen Elizabeth II, Prince Harry and Prince William, Duke of Cambridge, Pippa Middleton competed in a triathalon 73 miles away in Woodstock, according to Us Magazine.

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At the GE Blenheim Triathalon, held at Blenheim Palace, Pip Pip Hooray went head-to-head with a shirtless male competitor as they crossed the finish line.  Ever-so-mindful of the attention her figure got at the royal wedding, Middleton is most likely keen to keep her famous behind in check.  This isn’t a new hobby Catherine’s younger sister picked up, though.  The Middleton girls have always been athletic, keeping fit through a variety activities including tennis, skiing, swimming and running.  Pippa recently endorsed a pilates studio she uses in London to prepare for her sister’s wedding.