The cocoon crunch is a bodyweight exercise targeting the ab muscles, the rectus abdominis or "six-pack" muscles in particular. It involves bringing your knees to your chest and your arms from overhead to center. It can be performed for time or reps as part of the ab-focused portion of any workout.
Builds the rectus abdominis and the obliques
Both stretches and contracts ab muscles
Difficulty increased by moving both arms and legs simultaneously