Start: Attach a straight bar to the low pulley, and place a bench crossways in front of the cable column Grab the bar with an underhand grip, kneel next to the far side of the bench, and rest your forearms on the bench with your wrists hanging off the other side. Roll the bar down to your fingertips.
Finish: Roll the bar back up, and flex your wrist so your palms curl up toward your elbows. Pause, then return to the starting position.