Cable reverse crunch

Attach a cable to a low pulley and lie down facing up on a mat. Hold the cable with both hands and extend your arms straight up towards the ceiling. Bend your knees and lift your legs up, bringing your thighs towards your chest. While keeping your upper body stable, curl your pelvis up towards your chest, lifting your hips off the mat. Pause for a moment at the top, then slowly lower your hips back down to the starting position. Repeat for the desired number of repetitions.