Oblique's
A good exercise to perform on the Swiss Ball, as enables the muscles to be worked through a good range of movement whilst being comfortably stretched during the downward phase.
Aim to use a ball that is large enough to give full support to the side off your body during the downward phase, and enables your head to be inline with the center of the ball during the lifting phase. You may wish to place the ball in a corner of a room if you have poor balance.
Lie on the side of the ball, with both legs spread wide to aid stability, with your hands supporting the weight of your head, elbows pointing upwards.
Exhale and slowly lift your upper elbow, in the direction of your upper hip, whilst avoiding any forward flexion.
You will only need to lift a few inches in a slow controlled motion to feel the benefits of this exercise. Inhale as you slowly return all the way back down to the starting position again, prior to repeating the movement.
Avoid excessive speed, which will cause you to have a bouncing motion, which aids your lift. Intermediates may wish to perform the exercise with their arms across the chest, likewise advanced may decide to hold a suitable weight plate.
Beginners aim to work both sides for 8 - 12 reps.
Intermediates aim for 2 sets of 10 - 12 reps both sides.
Advanced aim for 3 sets of 12 reps+ both sides; however reduce the reps if using a heavy weight.