The Pro: Mari Winsor, one of the originators of Pilates-style workouts, has Pilates-ized half of Hollywood.
Core Clients: Winsor says that Miley Cyrus particularly likes this move, and has been known to rope fiancé Liam Hemsworth into doing it with her.
The Steps: 1. Sit on the floor, leaning sideways on your right hip, with your right arm on the mat supporting your body. Your legs should be slightly bent, with the left foot slightly in front of the right.
2. Use your core to lift your body up to a side plank.
3. Extend your left arm over your head.
4. With your abs pulled in tight, lower your hips (but don't let them touch the floor!) and your left arm, then press back up to the side plank.
5. Repeat this same lower and lift 6 to 8 times, then switch sides.