- Stand with your feet slightly wider than a hip's distance apart. Grasp a medicine ball with both hands at chest level with your elbows bent.
- Bend your knees, stick your butt back, and come into a squat.
- Continue to bend your knees as you bend forward from the hips, placing the medicine ball on the floor under your breastbone.
- Press your hands into the medicine ball as you jump and extend your legs behind your body, coming into a plank. Keep your abs tight the entire time. Recoil your legs and rise to the starting position. If necessary, you can do this move without the ball; just put your hands on the floor.
- Do three sets of 15 to 20 reps.
Photos: Shona Valeska courtesy of Ultimate New York Body Plan (McGraw-Hill)