The reverse crunch is a simple exercise, yet crucial to creating a strong and functional core for running. You can perform this exercise on the ground or hanging from a chin-up bar.
Preparation: Lay on the floor with both legs at 90 degrees. Hands should be placed on the ground for assistance is needed.
Execution: Slowly raise your low back off the ground. Do your best to avoid a rocking motion. Lower the legs back to the starting position. The slower the better on the way down! Your head should never leave the ground. Repeat 20-30x.
Notes: To increase the difficulty of this exercise, place a medicine ball between your knees.