Credit: Splash News Online

Duff's got the right stuff!

While vacationing with husband of one year Mike Comrie on the Island of Capri, Italy Monday, Hilary Duff, 23, showed off her womanly curves in a sexy black bikini. As her Pittsburgh Penguins player husband, 30, took pictures of her in a lagoon, the She Wants Me star struck a series of flirty poses.

How does Duff -- who shot to fame on Disney Channel's Lizzie McGuire in 2001 -- stay in such great shape?

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"I work with a trainer named Harley Pasternak and I do a lot of Pilates," she told Us Weekly in April. "I'm just like everyone else. I go through stages where I feel super motivated and want to work out every day, and then I won't work out for two or three weeks and I'll feel like s**t. Then it's time to hop back on the wagon again!"