Round Back

The Round Back ab exercise works your rectus and transversus abdominis.

Cinch-It Secret. Round Back. The key to this move is to sit a few inches away from the wall so that your back is rounded. Squeeze your abs as you bring your knees to your chest and straighten your legs. Do 10 pulses, bringing your legs an inch closer to the wall and back an inch. Do 3 sets total.