Sleeper Stretch

Lie on your side with the shoulder you're stretching underneath you, arm out in front at shoulder height and elbow bent to 90 degrees, forearm pointing up. Use your other hand to gently press that forearm down toward the floor, rotating your shoulder inward. Keep your shoulder blade pinned under you rather than letting it roll back to escape the stretch — that roll is what makes this feel harder than it needs to be. You'll feel this toward the back of your shoulder, not the front. Press only as far as feels like a stretch, not a pinch; this joint angle is unforgiving if you force it.