Kneel down under the lengthened TRX straps and place your feet into the handles.
Tighten your abdominal muscles and lift your knees up, so that you have a straight line from your head to your feet.
Use your core muscles to pull both knees diagonally in towards one shoulder, rotating your body as you move into the tuck position.
Control the movement as you straighten your legs back out to repeat the exercise on the other side.
