Lie on your side, either supporting your upper body on your elbow and forearm, resting your head in your hand, or even resting your head on a pillow.
Grasp a dumbbell with your free hand, bend your elbow to a 90-degree angle, rest your elbow against your side, and lower your forearm across your belly.
Execution
Keeping your elbow against your side, exhale as you raise the dumbbell as high as possible by externally rotating your shoulder.
Hold for a count of two.
Inhale as you slowly lower the dumbbell across your belly.
Repeat.
Repeat with your other arm while lying on your opposite side.
Comments and tips
Keep your elbow bent at a 90-degree angle.
Keep your elbow against your side. If it keeps rising off, it means that you’re using too heavy a weight and that your lateral deltoid is being recruited to complete the rep.
As with the cable face pull and the cable external shoulder rotation, the dumbbell lying external shoulder rotation promotes shoulder rotator cuff health by strengthening your external shoulder rotators and thus helping to prevent an imbalance between your internal and external shoulder rotator muscles.