Half Jack Knifes

Place your hands either side of your head, supporting the weight of your head, keeping your chin off your chest throughout the movement.

Begin the movement with both legs extended out to your front, resting your heels on the floor whilst keeping a slight bend in your legs, (aim to keep the calf's off the floor).

Exhale and slowly lift your from your shoulders your upper-body off the floor 8 - 12 inches whilst keeping your elbows pointing forward.

Concentrate on keeping the movement smooth without pulling down on your neck.

Whilst lifting your upper-body, bring one knee up towards the elbow on the same side, whilst keeping the other heel on the floor.

Lower back down under control, and repeat again on the other side.

Aim to develop the movement so that you can bring your knee up to touch your knee, rather than forcing your body pass a 30 degree lift which reduces abdominal contraction.

Focus on keeping the abs contracted throughout by keeping your shoulders off the floor during your repetitions. This exercise can be made harder by keeping both heels off the floor, however this can place excessive stress on the lower back.

Beginner's if wanting to perform this exercise, aim for 6 - 8 lifts each side repeated twice. Work within your own limits, it's not essential to produce the full range of movement in order to receive the benefits.

Intermediates aim for 10 - 12 slow reps each side repeated twice.

Advanced work for 15+ slow reps each side repeated 2 - 3 times.