Double Crunches with Medicine Ball
Place a lightweight medicine ball between your knees and lie flat on your back, abs engaged, lower back flat on the floor, and legs lifted into a tabletop position (knees bent, knees in line with hips and shins parallel to the floor). Bend your elbows and place your hands behind your head and neck for light support.
EXHALE: Keeping abs engaged and knees bent, use your abs to pull your knees toward your chest as you simultaneously lift your head, neck and shoulder blades. INHALE: Slowly return your legs to the starting (tabletop) position and release your upper body back down to complete one rep.
You may want to place your hands underneath your lower back for support. Don't use momentum to swing your legs in; practice control. Keep your elbows out to the sides to ensure that your arms aren't helping you lift your shoulder blades.
Muscles Worked: Abs, Inner thighs