miley cyrus

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The Move: Side Plank Variation

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.
Christina Applegate

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The Move: Plank Push-Ups

The Pro: Teddy Bass, celebrity trainer for over 19 years and creator of the Rock Bottom Body lower-body sculpting program.

Core Client: Christina Applegate used this move to help tone her core after giving birth to her daughter, says Bass.

The Steps: 1. Start in a plank position, with your weight on your forearms and your toes and body forming a straight line from head to toe.

2. Pushing off your forearms, pick up your right hand and place it on the mat under your right shoulder.

3. Lift your left hand and move it under your left shoulder. (You should be in a push-up position).

4. Drop back down to your right forearm, then to your left. (You should now be back in the starting position). Continue this push-up pattern (up right, up left, down right, down left) for a total of 5 reps.

5. Rest, then start over, leading with the left arm.
Britney Spears

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The Move: V-Sit Twist

The Pro: Derek DeGrazio, L.A.-based fitness expert and trainer.

Core Client: DeGrazio taught this move to Britney Spears while traveling with her on last year's Femme Fatale tour.

The Steps: 1. Sit on a mat with your knees bent, feet flat and arms by your side.

2. Bend your knees and lift your feet off the mat until your shins are nearly parallel to floor. Lean back 45 degrees so that your torso and your thighs form the letter V.

3. Hold a 6 to 10-pound medicine ball (or a dumbbell, or a jug of OJ) close to your chest with your elbows out.

4. Rotate your upper body to the right so that your left elbow is above your right hip. Then rotate to the left in the same way.

5. Do 3 sets of 30.
jennifer aniston

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The Move: Three-Legged Dogs

The Pro: Mandy Ingber, yoga and fitness instructor, and creator of the Yogalosophy Workout DVD .

Core Client: Ingber introduced Jennifer Aniston to yoga and helped her perfect this ab-busting sequence.

The Steps: 1. Start in a push-up position. Lift your right heel until it’s no higher than your shoulder.

2. Draw your right knee to your forehead, rounding your spine; inhale and extend your leg back again.

3. Exhale and bring your right knee to outside your right triceps; inhale and extend your leg.

4. Exhale and cross your right knee to your left elbow; inhale and extend your leg. Do this sequence 3 times, then switch legs and repeat. (These illustrations can help you master the steps.)

Next: How to get arms like Michelle Obama