Position
Adjust the machine to begin with your hips and knees flexed to form approximately a 90-degree angle or as close to it as possible while being able to create a natural arch in your lower back. Lie on the machine in a ready position with your sacrum and shoulder blades pressed firmly against the back pad.
Technique
Slowly begin straightening your legs, keeping the weight over your ankles and a natural arch in your lower back. Extend your legs to a straight position without locking your knees. Hold, continue to contract your glutes, quads, and hamstrings, and stabilize with your trunk muscles. Lower the body back to its original starting position while maintaining a proper spinal position. Repeat.