Build your six-pack with this ab-toning move.
-Butterfly Crunch: Lie down with the soles of your feet together and pull them towards your body. Put your hands behind your head. Now, exhale and curl your chest a few inches up off the floor, lower back down. Crunch up again for 10 reps. Be sure to keep your lower back flat on the floor and your stomach muscles tight. This move works your rectus abdominis, or your 6 pack.