Being around volleyball my entire life has exposed me to a variety of injuries specific to the sport. One of the most frustrating and debilitating injuries a lot of volleyball athletes will deal with is shoulder pain. More often than not, shoulder pain is the result of an overuse injury that develops over time and is rarely an acute, “one single incident” type of injury. Of course there is also the argument of correct form and correct mechanics, but we are not going to go into that in this article.
This article is going to specifically address injuries to the volleyball hitting shoulder that outside hitters, middle blockers, and right side hitters will more than likely experience at some time in their careers. With the start of the fall high school season upon us, now is a good time to discuss some ways to keep your shoulder healthy for the season.
Simply put, the volleyball arm swing is utilized to direct the ball in a forceful manner in order to score points. This is either through the serve or coming from a set. The velocity and torque that occurs in the shoulder complex is under appreciated by most athletes and coaches. Especially when the goals are to make a team, or win matches, or earn college scholarships, etc. This can lead to repetition after repetition placing more and more strain on the shoulder complex.
We are going to simplify the arm swing into three phases: 1) The loading phase, 2) the acceleration phase, and 3) the deceleration phase. As with all athletic movements, the volleyball arm swing is not an isolated movement and the ability to engage and utilize back, core, and hip muscles must be included in order to provide power and to protect the shoulder complex. Again, for the purposes of this article we are going to focus on just the shoulder (the glenohumeral and scapulothoracic joints) and the primary muscles involved in the arm swing.
The loading phase: During this phase the elbow is flexed and the arm brought back into extension and external rotation (much like the baseball pitcher winding up to throw a baseball). This requires a lot of moving pieces: the scapulothoracic joint should retract, the thoracic vertebrae extend and rotate, and the elbow is brought back behind midline as the upper arm rotates into external rotation. All of this happens very quickly and loads the arm for the explosive movement that will provide the power that occurs at ball contact. Optimizing anterior shoulder muscle strength and increasing joint mobility will provide the power needed to increase arm swing velocity.
The acceleration phase: once the arm is fully loaded, tension on the accelerator muscles is at their peak and the body begins to contract the powerful muscles that provide the speed and power to swing through the ball. This violent and dynamic movement is accomplished from the toes all the way up to the tip of the fingers. As for the shoulder complex, we see the engagement of the pectoral muscles, the subscapularis (rotator cuff muscle), the latissimus dorsi, teres major, the anterior serratus, the triceps, and the posterior deltoid as they move the arm forward extending the arm, internally rotating the glenohumeral joint, and driving the hand through contact point with the ball.
The deceleration phase: instantaneously after the ball has been contacted, the arm must now go through the deceleration phase which also includes following through the ball. Immediately following the acceleration phase, the arm must now slow down placing an eccentric force on the posterior shoulder muscles: infraspinatus & teres minor (rotator cuff muscles), rhomboids, middle and lower traps, anterior deltoid, and biceps brachii. If you ever get a chance to look at these muscles, it is amazing how little mass they have when compared to the muscles involved in the acceleration phase. These deceleration muscles will get fatigued throughout a practice, a match, a season, and a career. When this happens we start to see abnormal stress to some of the non-contractile tissues in the shoulder complex. If the decelerator muscles cannot provide enough support in this phase, the head of the humerus will glide forward causing excessive stress to the anterior labrum and joint capsule as well as the biceps tendon. This glide can also cause a shear force to the cartilage that covers the glenoid (the cup) and the humerus (the ball) of the shoulder. Over a couple of seasons, this can lead to cartilage break down and early arthritis issues. If these deceleration muscles get over-worked they will start to break down and develop tendonitis and/or tendosis. And when these things start to happen we see altered swing mechanics which leads to things like impingement, bursitis, and/or compensatory movements.
As you can see, there is a lot to consider when analyzing the volleyball arm swing and how one individual’s specific mechanics, range of motion, strengths & weaknesses, age, experience, etc. factor in to how and why shoulder pain has started. There is also a lot to consider when it comes to developing a plan to restore the shoulder to optimal performance. Ultimately, when dealing with shoulder, you should see an expert physical therapist who understands the demands of volleyball to customize a rehab program for you. In the meantime, here are some foundational exercises and stretches that all volleyball players should be doing.
Rows – bent over rows, pulleys, bands, TRX, etc.; this exercise emphasizes middle and lower trap, rhomboid, and posterior deltoid activation which are vey important to stabilize the shoulder blade throughout the arm swing. Just like it sounds you perform this exercise by pulling your hands in towards your armpits by drawing your elbow and shoulder blades back towards your spine. Can be performed one arm at a time or both together.
Scaption – specifically addressing the supraspinatus (one of four rotator cuff muscles) this exercise is performed most accurately in studying with arms hanging by the side. Lift arms up at a 45 degree angle up towards your ears. Start with light dumbbells, but try to increase weight up to 10# or more.
Straight arm pull downs – Keeping your arm straight as a board, hold a handle on a pulley or the end of a piece of therband and pull down to your hip. Again, can be done with one arm at a time or both arms together. Great for posterior deltoid and lower scapular stabilizing muscles.
External Rotation – Very important rotator cuff exercise. Stand with arm at side and elbow bent to 90degrees while holding the end of a thiraband or the handle of a pulley. The pulley rope/band should be anchored off to the inside of the arm you are working so that your palm is positioned at your belly button. Rotated the arm out to the side so that your hand is outside of your body.
Foam Roller Series – This is used to improve mobility and range of motion throughout the thoracic spine, glenohumeral joint, and scapulothoracic joints. First, lay on the roller with your head at one and your butt at the other end. Lay with your arms straight out to the side (like you are on the cross) with palms up. You should feel a stretch across your chest. Hold for 30 seconds. Next, move the foam roller so that it is perpendicular to your spine and sit on the floor and rest your shoulder blades against the foam roller. Then lift your butt off the floor and roll up and down on the foam roller from your shoulder to the bottom of your rib cage. Perform 10-20 times.
Good luck! Stay strong and keep working hard!
John-Henry Anderson, PT, DPT, SCS, CSCS is a Board Certified Sports Clinical Specialist and a Strength & Condition Specialist at our APRS Physical Therapy West clinic. When not working as a PT he coaches for Big Sky Volleyball Club and competes around the region in both indoor and beach volleyball.