This exercise originally appeared in the 905 issue of OptiMYz magazine as part of the Fast Abs workout by Nichelle Laus and Holly Weselowski.

PRISONER GET UPS
A Lie flat on your back on the floor with your hands placed behind your head, elbows outwards.
B–C Bend your knees and keep your feet on the floor. Then, using your lower ab muscles, bring yourself forward until your butt and the heels of your feet are close.
D–E With your hands behind your head, hinge at your hips and get up off the floor, standing up straight without using your hands, just your legs. Return to starting position and repeat.

More inspiration? Here’s another workout to try, the Upper Body Burn