The subscapularis works with other muscles and tendons to attach your shoulder blade to your upper arm. As part of your rotator cuff, this large, thick muscle keeps the ball of your upper arm snug and stable in your shoulder socket. Stretching the subscapularis daily helps maintain or increase flexibility and improve joint range of motion. That translates into healthier, more functional shoulders and greater resistance to injury. For a simple but thorough stretch, all you need is a few minutes of free time and an open doorway.
Of the four muscles that make up the rotator cuff, the triangular subscapularis is the most anterior and most powerful. It adducts and medially rotates the arm, meaning it pulls the arm toward your body and rotates it inward. Sports that involve repetitive inward rotation of the arm, such as tennis, swimming and baseball put a great deal of strain on the subscapularis. House painting, construction and other activities that involve repeatedly lifting the arms overhead are equally taxing. Individuals who regularly engage in such activities are more susceptible to injury of the subscapularis. Exercises such as the door-frame stretch help keep the risk of injury in check.
To perform the stretch, stand facing an open door with your right foot staggered in front of your left. Place your right hand on the right door frame or on the wall to the right of the door frame. Your right elbow should be bent at 90 degrees, and your hand should be level with your head. Keeping your shoulders square to the front, shift your hips forward slightly and bend a bit at the waist. You'll feel slight tension along the front of your right shoulder. Hold the position for up to 30 seconds. Relax briefly and repeat the stretch two to four times. Place your left hand and lower arm on the door frame, and repeat the stretch for your left subscapularis.
Tips and Variations
Stretching one shoulder at a time allows you to carefully monitor the stretch sensation on each side. If you prefer, or if you're pressed for time, stretch both shoulders simultaneously. Simply place one hand on each side of the door frame and hinge forward. You can also change the height of your hand on the frame, extending the elbow as necessary. Moving your hand higher or lower helps you target different muscle fibers for more thorough coverage of the muscle. With all variations, keep both knees slightly bent to prevent hamstring tightness from inhibiting the stretch.
Always maintain total control over the movement, and avoid bouncing, jerking or falling into the stretch position too abruptly. Applying too much force or moving into the stretch too quickly can result in injury. Dr. Christopher Notley, a certified athletic therapist, notes that the door frame stretch is not recommended for individuals with a history of shoulder instability or dislocation. Certainly, if you have injured your shoulder in the past, consult with your doctor, physical therapist or personal trainer about the advisability of specific shoulder stretches.