Target your abs and your hamstrings with this multi-muscle move!
Sit with your hands behind your head, spine straight. Bend your knees and flex your feet so that just your heels are pressed into the plates. Slide your legs out straight as you hinge back, lowering all the way down to the floor with your body, sliding your legs out into a wide 'V' position. Bend your knees and use your abs to return to your starting position, sliding your heels into your body as you sit up. That's one rep. Do 15 reps total.
Tip: Focus on digging your heels into the plates to maximize the effort from your hamstrings.