Piriformis Stretch

Sit on a chair or the edge of a bench and cross one ankle over the opposite knee. Keep your back upright and use your hand to gently press the crossed knee down and away from you rather than folding your torso forward to find the stretch. That press-and-hold isolates the deep rotator under your glute more directly than leaning does, and it's easier on your lower back if hinging forward bothers you. You'll feel this stretch sitting deep in your glute, roughly where you'd find your back pocket. Keep even weight through both sit bones instead of shifting onto the straight leg.