The Secret to Kelly Ripa, Sarah Jessica Parker and Naomi Watts's Svelte Physiques

How do Kelly Ripa, Sarah Jessica Parker, Shakira and Naomi Watts keep their sleek shapes? By hitting the dance floor! The stars are all dedicated to a movement-centric workout created by celebrity trainer Anna Kaiser. “It’s my new fitness obsession. I am here four times a week minimum,” Ripa told InStyle.com at the launch party for the new AKT inMotion Studio in NYC, where she heads for her workouts. “I think [Kaiser] understands the human body in a really profound way. She studies the human body, and so I think she’s been able to even my body out. I was a little crooked all my life and I never even knew it.” But the workout -- a combination of everything from yoga and dance to strength training and plyometrics -- does more than burns calories. For Ripa, she’s reaped the benefit of learning new skills that she’s taking with her outside the gym. “When we go out, I’m on the dance floor the entire time, because I feel like I have skills now,” she jokes of how the workout has taught her coordination. But what is no joke is the work that she and other stars put in while sweating it out during a session. “At the end of class, we take our shirts and ring them out and it’s disgusting,” she says. And when it comes to maintaining her regime outside the studio, Ripa says it’s all about moderation and making sure you’re enjoying life—just not overdoing it. “For me, I work so hard to maintain it, to blow it all on a piece of cheesecake doesn’t make any sense to me,” she says. “What does make sense to me is an extra glass of wine. That’s sort of how I look at it -- it has to be worth it, and an extra glass of wine is worth it!” Can't make it to Kaiser's NYC studio? Try out Kaiser's 10-minute butt workout , and stay tuned for a series of DVDs that are also in the works.

Plus, see more star workouts!

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