Works: core and obliques
Lie face up on a mat with your feet off the floor, knees bent and arms extended overhead [not shown]. For added resistance, hold a medicine ball between your knees and a weighted mini ball in your hands. Rotate from your lower back to drop your knees towards the floor on your left. Return to the center and perform a crunch.
Perform 3 sets of 10 reps on each side.
Photos courtesy of 24 Hour Fitness
