How To: Lie down on a decline bench with your legs fully extended and arms to the side of your torso with the palms on the bench. Move your legs up so that your thighs are perpendicular to the bench and feet are together and parallel to the bench. While inhaling, move your legs towards the torso as you roll your pelvis by raising your hips off the floor. At the end of this movement your knees will be close to your chest. Hold for a second and move your legs back to the starting position while exhaling.
Muscles Used: Core