Sit on the floor with feet firmly planted, knees bent, back straight, and hands gripping a medicine ball or dumbbell (not pictured). Bend your elbows and tuck them in at your sides, holding the ball or dumbbell in front of your torso. Keeping a your back straight, lean back (hinging from the hips) until you feel your abs engage. From there, carefully lift your feet off of the floor to balance.
EXHALE: Keeping a perfectly straight back with your abs pulled in tight, rotate your torso to the right as far as you can while maintaining good form (back straight, maintaining balance).
INHALE. Return to the center (start position).
Repeat on the opposite side to complete one rep.
Do not round or arch your back. Focus on the movement coming from the waist, allowing your upper body and arms to follow the twisting motion of the waist.
Make it harder: Use a heavier weight and/or extend your arms straight out in front of you.
Make it easier: Perform this exercise without holding any weight.
Muscles Worked: Abs, Obliques, Hips
Click here to read about selecting the proper amount of weight.