The hamstring and glute stretcher. Hinge, don't squat.
Lead with your hips going back, the bar stays glued to your legs the whole way.
The RDL is a pure hip hinge: knees stay softly bent while the hips travel back, loading the hamstrings through a long, weighted stretch that almost nothing else matches. The glutes then snap the hips forward to finish each rep. Because the bar starts from the top and never touches the floor, tension never leaves the hamstrings, which is exactly why it is the default hamstring builder in most programmes.
As low as you can with a flat back and the bar on your legs, usually around mid shin. The rep ends where your hamstring stretch peaks, not where the plates touch the floor.
A deadlift starts from a dead stop on the floor with more knee bend and more quad involvement. The RDL starts standing, keeps the knees mostly fixed and lives in the hip hinge, so the hamstrings and glutes take nearly all of it.
Usually the bar has drifted away from your legs or your spine is rounding. Drag the bar down your thighs, push your hips back rather than bending your torso down, and cut the depth to where your back stays flat.
