Attach a rope handle to a high pulley on a cable machine
Kneel facing the machine with the rope behind your head
Hold the rope ends beside your head or at your temples
Keep your hips fixed and your lower body still
Brace your core and slightly tuck your chin
Crunch your torso downward by curling your ribs toward your pelvis
Exhale as you contract your abs
Pause briefly at the bottom of the movement
Return slowly to the starting position under control
Keep the movement driven by your abs, not your arms or hips
Use a weight that lets you maintain strict form
Repeat for the desired number of reps