Balance the cuff from the inside out.
Only the forearm moves. Keep that elbow locked to your side the whole time.
This is the mirror image of external rotation work, with your elbow tucked at 90 degrees, rotating your forearm across your stomach trains the internal rotators at the front of the shoulder, one arm at a time against the stack's smooth pull. It's less famous than its external twin, but a balanced cuff needs both directions trained. It earns its place in shoulder care work, keeping the joint's rotators matched so nothing gets to dominate.
Bigger muscles like your chest and lats do assist internal rotation, but the small cuff muscle that fine-tunes it still benefits from direct, controlled work. Light targeted reps train control, not just force.
Letting the elbow leave the ribs. The instant it drifts, the movement becomes a weak press across your body, keep the elbow welded to your side and let only the forearm travel.
Very. This is a small muscle doing a short arc, so pick a weight you can rotate slowly for 12 to 15 reps per arm with zero body lean, if the stack clanks, you're rushing.
