One leg, landmine arc, locked-in hamstring stretch.
Keep your hips level and let the fixed bar path guide you, don't twist toward the loaded side.
Balancing on one leg while hinging along the landmine's fixed arc puts the entire stretch and drive through one hamstring, with the glute on that side controlling the hip and powering the stand. The anchored bar is the difference maker, it steadies the wobble that ruins most single leg RDLs, so you can actually load the movement instead of just fighting for balance. It earns its place for building each leg's hinge strength independently and exposing left to right gaps.
The bar is fixed at one end, so it gently resists side to side wobble and gives your hinge a rail to follow. You get the single leg training effect with far less time wasted stumbling out of reps.
Hold it in the hand opposite your standing leg, that offset loads the standing hip properly and helps keep your pelvis square. Holding on the same side is a variation, but start with the opposite grip.
Think about pointing the back leg's toes straight down at the floor and keeping both hip bones facing the ground. If they still swing open, shorten the range and lighten the bar until you can stay square.
