Glute-Ham Developer (GHD)

How to adjust

Adjust the footplate/roller distance from the hip pad to match your leg length — this is the key GHD-specific adjustment.
Adjust the hip pad height as needed.

For a glute-ham raise: wedge your feet against the footplate between the rollers, upper thighs on the hip pad, starting in a tall kneeling position.
Lower your torso forward by letting the knees straighten out, keeping the hips extended and the body in one line from knee to head.
Exhale and bend the knees to pull your torso back up to tall kneeling with the hamstrings and glutes, without yanking with the lower back.
For a back extension, set the machine up in the prone position like a 45° bench and hinge only at the hips.
If you run out of strength mid-set, put both hands on the pad or the floor to take some of your weight, push yourself back to kneeling, and only then pull your feet out of the rollers and step down.

Set the footplate distance for your leg length and test the ankle lock with a small lean before committing your full bodyweight, since the GHD's higher difficulty and knee-hinge mechanism make an insecure setup more likely to cause a fall.
If you run out of strength or start sinking mid-set, put both hands down on the pad or floor to catch yourself and push back to kneeling; only unhook your feet once your body is upright and your hands can still hold you.
Don't let your torso drop uncontrolled, especially on the first rep of a set.
Progress the range gradually since a true glute-ham raise is more demanding than a standard back extension.