Nordic Hamstring Curls

Begin by kneeling on a pad (for knee comfort) or using a machine as shown in the video. Slowly lowering under control while the ankles are held in place by a partner or the pads on a machine using a loaded barbell, or any other immovable object (like a weight bar as shown).
Then extend the hamstring muscles to lean forward, lean forward from the knee, not from the hip. The movement should be slow and controlled.
Come as forward or low to the floor as you can without using your hands/arms. Only put your hands out in front of you on the floor when you can no longer rely on your legs. Then push yourself back up to starting position and repeat for desired number of reps.