This exercise is great for your lower abdominal muscles.
Lie on the floor on your back. Head and shoulders are both resting on the floor. Place your hands by your sides. Your feet are up with your thighs perpendicular to the floor and your calves parallel to the floor, forming approximately 75 degree angle.
Roll your pelvis backward to raise your hips off the floor, using your lower abs. When you reach the highest point of the exercise, your knees will now be over your c