An excellent exercise for your obliques. Ideal for beginners who want to feel their abs burning with no equipment.
Lie on the floor on your side, with one foot stacked on top of the other.
For stability place your bottom arm straight out to the side with your palm down. Position your top arm with your hand behind your head and elbow pointed straight up.
Exhale and pull your knee until your thigh is perpendicular. At the same time crunch your body up and touch the elbow of your top arm to your top knee.
Do not pull your head as you crunch your body to the side.
Inhale on your way down and repeat.