As it turns out, this exercise has a fancy name – the suitcase crunch (since you fold your body together like you’re shutting a suitcase.)
Step 1: Lie on your back. Your legs should be in the air, and your hands should be beside your ears.
Step 2: Contract your abs and lift your hips a few inches off the floor. At the same time, lift your head and shoulders towards the ceiling.
You are basically doing two crunches in one movement.
Then lower back to the starting position and repeat.
Suitcase Crunch video:
See more exercise guides in The Bodyweight Exercise Collection.