Stand between two very low pulleys with shoulder width or narrower stance. Squat down and grasp stirrup attachments to each side. Stand upright with arms straight down to sides.
With knees straight, bow forward by bending hips. Bend waist as stirrups approach lowest position. Lift dumbbells by extending hips and waist until standing upright. Pull shoulders back slightly if rounded. Repeat.
Begin with very light weight and add additional weight gradually to allow lower back adequate adaptation. Throughout lift, keep arms and knees straight. Do not stand behind pulleys. Do not pause or bounce at bottom of lift. Lower back may bend slightly during full hip flexion phase. Do not lower weight beyond mild stretch throughout hamstrings and low back. Full range of motion will vary from person to person depending on flexibility. See Dangerous Exercise Essay. Also see Straight Back Straight Leg Deadlift.