Wrap a band around a power rack or pole several inches above its lowest point.
Lie on the ground with your arms bent, feet hooked into either end of the band, and hands behind your head.
Exhale and begin to raise your torso diagonally across your body while simultaneously bringing your opposite leg up toward your chest by bending it. Do not use your arms to pull on your head.
Continue raising your torso and bringing your leg toward your chest as far as you can without allowing your lower back to leave the ground or leg to rotate.
Inhale and simultaneously lower your torso and extend your leg, returning to the starting position on the ground.