- Lie face up on your mat and place your hands behind your head, lightly supporting it with your fingers.
- Bring the knees in to the chest and lift the shoulder blades off the floor without pulling on the neck.
- Rotate to the left, bringing the right elbow towards the left knee as you straighten the other leg.
- Switch sides, bringing the left elbow towards the right knee.
- Continue alternating sides in a 'pedaling' motion for 1-3 sets of 12-16 reps.
View this video for more detailed instructions.
If you have difficulty with this move, you can try a modified version.
View this exercise in the Best Ab Workout.
Next: Captain's Chair