Banded clams that crank up the glute medius burn.
Keep your hips stacked and don't roll back. The band should make every rep harder, not your momentum.
Lying on your side with feet stacked and knees bent, opening the top knee is rotation at the hip, which is glute medius territory, the abductors along the outer hip lifting against the band's pull. The range is small on purpose, it keeps the work in the hip instead of the spine. Done strictly one side at a time, it is the classic drill for the muscle that stops knees collapsing inward when you squat, run, or land.
You are probably rolling your top hip backward to fake extra range, which hands the work to other muscles. Keep your hips stacked vertically and open the knee only as far as the outer glute can take it.
High reps per side, this is an endurance and control muscle, not a max-strength one. Chase the burn along the outer hip rather than adding range or speed.
Yes, squats load the glute med but rarely to its limit, and a weak one shows up as knees caving under fatigue. A couple of banded sets before leg day covers the gap cheaply.
