This is a variation of the straight Roman Chair sit-up exercise.
While the Roman Chair exercise places intense stress on the entire rectus abdominus the twists also recruit the fibers of the intercoastals and to a lesser degree obliques.
How to do:
1. Sit on the Roman Chair and hook your toes beneath the restraint bar near the floor.
2. Cross your arms over your chest. You will keep your arms positioned this way throughout the entire exercise.
3. Bend your body backward moving your hips until your back is about 6 inches above a point parallel with the floor.
4. Move forward until you feel your abdominal muscles relax.
5. Crunch your shoulders forward and down putting intense stress on the abdominals.
6. Relax and respect the movement downward until your back is 6 inches above a parallel plane to the floor.
7. Continue until you have completed the desired repetitions.
8. Resistance may be added by propping the front end of Roman Chair on a large block of wood.
9. Continue similar rocking movements only alternately twist to the left and to the right. Complete your desired number of repetitions.