Corgel said these work your rectus abdominis.
- Lie on your back on the floor, holding a dumbbell in your hands.
- Raise your arms and legs up to the ceiling. They should be as straight as possible.
- Lift your head and shoulder blades off the floor as you reach your hands toward your toes, keeping your legs up toward the ceiling. Keep your lower back glued to the mat.
- With control, return your shoulders back to the mat (your arms and legs should still be up toward the ceiling). This counts as one rep.