By: Dr. Maria Kaczmarczyk, DPT
Hey tennis players! Did you know that the shoulder (glenohumeral joint) is the most unstable joint in the body? Tennis is an excellent way to build up strength in your shoulder but, on the other hand, an excessive amount of high-impact shoulder use and overhead activities can overload various structures around the shoulder leading to injuries. Think of the glenohumeral joint as a golf ball on a tee. The top of the humerus (upper arm bone) is rounded and fits into the shallow socket of the scapula (shoulder blade), called the glenoid cavity creating a ball-and-socket joint. This allows for circular movement of the arm allowing you to hit that forehand smash. Optimal shoulder function requires a well-balanced action of the rotator cuff muscles and capsular structures to obtain a stable center of rotation, especially during overhead actions such as a serve.
Why is the rotator cuff important for tennis players?
The rotator cuff is the group of 4 muscles and their tendons, which provides strength and stability during shoulder motion. The four muscles are the Supraspinatus, Infraspinatus, Teres Minor and Subscapularis (SITS muscles). They originate at the scapula and insert at the head of the humerus forming a cuff around the glenohumeral joint. Think of these muscles as the deep “core” muscles of the shoulder. Their main function is to stabilize and center the humeral head within that shallow, small glenoid fossa, preventing the head of the humerus from sliding during arm movements. Weakness of the rotator cuff means that the head of the humerus is not staying in the center of the socket which can lead to mechanical obstruction. Overuse due to overhead activities such as tennis makes you more susceptible to shoulder injuries which is why it is so important to keep your rotator cuff muscles strong!
Simple exercises you can do to strengthen your rotator cuff muscles:
Scapular Plane Elevation: Place one end of the theraband under your foot and one in your hand. Set your shoulder back and down, keep your elbow straight and then lift your arm up in the scapular plane which is 30 degrees from midline. Keep your core engaged!
Sidelying External Rotation: Grab a light weight (trust me!) and place a towel under your arm. Form a 90-degree angle at your elbow. Set your shoulder back and down and then lift the weight up making sure your arm stays at your side against the towel and you maintain that 90-degree angle with your elbow!
External rotation at 90 Degrees of Abduction: Create a 90-degree angle at your elbow and lift your arm up to the side so your elbow is aligned with your shoulder at 90 degrees. Starting with the palm facing down then roll your shoulder back so that your forearm is directed upward. Make sure your elbow does not move, think of your elbow as a fixed axis. Keep your core engaged and shoulder back and down!
Internal rotation with resistance band: Secure an exercise band around a doorknob or table leg. Stand/sit sideways to the anchor, and hold the band in your hand away from your body. Keeping your elbow bent to 90 degrees and close to your side, rotate your arm in toward your stomach. . Keep your elbow near your side the entire time.
Internal rotation at 90 Degrees of Abduction: Stand facing away, grab the resistance band (that is attached at belly height), elevate your arm so your shoulder and elbow are 90 degrees. Rotate your arm on the axis of your humerus so your palm comes to the ground. Do not let your elbow or shoulder move other than the rotation. If there is any discomfort, lower your elbow slightly. Keep your core engaged!
RTC combination with resistance band: Keep your arm about 90 degrees away from the side of your body. Facing the resistance band hold onto the end of the band, draw back the band by retracting your shoulder blade forming a 90-degree angle at your elbow. Then roll your shoulder back so that your forearm is directed upward. Then press the arm towards the ceiling without letting the resistance band pull your arm forward! Remember to keep your core engaged to avoid compensations.
10-15 reps 2-3 sets! 3x/week
These exercises are for people who would like to prevent shoulder injuries. If you are currently having shoulder pain and or experiencing pain with these exercises stop and come to Physio Logic for a full physical therapy consultation.