Roman Oblique
Position yourself in a comfortable position on a Roman Chair, with both legs supported under the lower feet restraints at ankle height, with your feet pointing upwards.
Your legs should be straight, with your both buttocks resting on the upper (torso) pad.
Slowly lean back, no further than a horizontal line through your ankles and hips, placing your hands either across your chest (easier) or supporting the weight of your head.
Using your abs, keep this body positioned fixed, with your hips facing upwards, whilst twisting only a few inches from your waist, facing in the direction that you're twisting throughout the movement.
Concentrate on the keeping the movements slow, smooth and under control, exhaling as you twist up, then inhaling during the lowering phase.
You can work one side at a time (harder) or alternate each side, however always come back to the starting neutral position prior to initiating the next movement.
Beginners or persons with lower back pain should avoid this exercise.
Intermediates aim for 8 - 15 slow turns each side, come off the machine and repeat again 30 seconds later.
Advanced aim for 8 - 15 slow turns one side, then perform again on the other side, prior to coming off the machine and repeating again 20 - 30 seconds later.
Throughout the exercise, all of your abs are working to keep your body fixed in the extended position, and as such you may find that you are unable to perform the same amount of reps when switching sides, never force your reps.