Sit on floor with knees bent and feet ... says Stewart. Lie face-up on floor, holding a medicine ball between your hands above chest. Bring knees into chest, shins parallel to floor.

Don't know what to do with that medicine ball? Here are 23 of the best medicine ball exercises from a trainer to strengthen ...

When most people think of a strong core or achieving abs, the first exercise that comes to mind is often sit-ups. While sit-ups ... at NYU Grossman School of Medicine, chief of Obstetrics and ...

Half sit up Sit up straight with your knees bent and ... to your body to make the exercise easier or hold a dumbbell or medicine ball for extra intensity. 9. Beast with shoulder tap Get on all ...