How to do it:1. Reverse Crunch with Hand Targets: Lie on your back with knees bent as far as possible toward your torso and, keeping elbows at sides, angle arms back with palms facing knees. Lift hips, performing a reverse crunch, so knees touch palms. Lower back down and repeat.
2. Arm Offset Crunch: Lie on your back on a stability ball with edge of ball at your sacrum. Extend right arm straight out to the side at 90 degrees, palm up, keeping left arm down at side. Lift up into a crunch, then lower back down to start; switch arms and repeat.
3. Lateral Rolling Plank: Cross your arms, holding onto your elbows, and place them on the stability ball so you're in a modified plank position. Roll to your right shoulder, then back to center and to your left. Continue alternating.
4. Rotating Crunch with Lateral Arm Swing: Lie on your back on a stability ball with left arm extended straight out to the side and right arm folded over chest. Lift up into a crunch, extending arms and swinging them to the right until left arm is bent over chest and right arm is straight. Continue alternating.
5. Reverse Crunch with Stability Ball: Lie on your back with knees bent, arms extended at sides at a 45-degree angle, and calves on top of stability ball. Squeeze the stability ball between your calves and thighs so it hovers above the floor. Lift your hips to perform a reverse crunch, then lower back to hover and repeat.
6. Hip Roll with Thread the Needle: Place the top of your feet on a stability ball and push up into a high plank position. Lift right foot up and over the left foot, then bring it back to the right and thread it under your left foot, extending right foot out to left. Do all reps on right side, then repeat on the opposite side.