Lie supine on sled with shoulders against pad. Place feet on platform.
Extend hips and knees. Flex hips and knees to descend until knees are just short of complete flexion. Repeat.
Adjust machine to accommodate near full range of motion without forcing hips to rise at waist. Keep knees pointed same directions as feet. Do not allow heels to raise off of platform, pushing with both heel and forefoot. Placing feet slightly high on platform emphasizes Gluteus Maximus. Placing feet slightly lower on platform emphasizes Quadriceps.