Starting Position: Lie on your back on an exercise mat or firm surface, with your knees bent and feet flat on the floor. Take your arms out to a "T" position then bend your elbows so that your forearms are vertical to the floor. Wrists are neutral, in line with your forearm. Breathe deeply and relax your body into the floor.
Pull your shoulder blades down and back without increasing the arch in your low back or lifting your ribs or hips off the floor. Hold this position throughout the exercise.
External Rotation: Gently rotate your forearms backwards toward the floor without arching your lower back, your ribs or changing your wrist position. Your goal is to rotate your forearms backwards until the backs of forearms, wrists and hands all make contact with the floor and are aligned together. Hold this position for 15-30 seconds before slowly returning to your starting position.
Internal Rotation: Gently rotate your forearms forward towards the floor without moving your torso or raising the backs of your shoulders off the floor. Your goal is to rotate your forearms forward until the fronts of your hands are 2-4" off the floor. Keep your forearms, wrists and hands aligned and hold this position for 15-30 seconds before slowly returning to your starting position.
This exercise stretches and strengthens your rotator cuff muscles in your shoulders in a stable and isolated manner. Healthy rotator cuff muscles permit healthy joint movements at the shoulder, reducing your likelihood of injury and pain. Try to perform this exercise next to a mirror that will allow you to monitor any undesired movement in the hips, ribs, shoulder or low-back. This is a good warm-up exercise to prepare the shoulders for heavier loads during exercises like the dumbbell bench press or standing barbell shoulder press.