Britney #1 On OK!'s 10 Best Bodies Of 2009

#1: Britney Spears

"She has the ideal body," Ashley Greene tells OK! of Brit, 27, who burns up to 550 calories an hour on the Circus stage. In L.A., Brit does two-hour cardio and strength sessions three times a week and relies on Sunfare's, 1,200-calorie-a-day deliveries. 

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