This exercise is great for entire abdominal area, and especially for your side obliques. To make this exercise even more advanced use wrist weights.
Lie flat with your head resting on the floor and your fingers overlapping behind your head. You knees are bent and forming 90 degree angle and resting on a flat bench.
Raise and rotate your upper body. With your right shoulder approach your left knee, but you do not need to touch it. When raising and rotating your body, tr