HOW: Get set up in a seated position on the ground. Sit up with your knees bent up. Lean back with a flat back and lift your feet off of the ground maintaining the bend in your knee. Use both hands to rotate from side to side as you keep your lower body relatively still. Rotate from your upper body from side to side for the prescribed amount of reps.
FEEL: You should feel your core and hip flexors working while performing this exercise.
COMPENSATION: Keep your back flat, don’t arch it. Don’t go too fast and move your body too much, focus on just rotating your upper half.