The average committed junior tennis player spends anywhere from 8-12 hours on the tennis court per week. Volume, consistency, and repetition are key components for tennis development. This equates to around 1,200 - 2,000 combined groundstrokes and serves per week. With every contact of the racket with the tennis ball, force is exerted upon the shoulder joint and the surrounding muscles and tendons. This knowledge helps us to understand the amount of work placed on the shoulder.
Athletes often become more susceptible to shoulder injury when an increase in total volume reaches above 25% from an average week. This sometimes happens during tournament play where an athlete may take up to 100-200% more strokes than an average week depending on how deep he/she plays into a tournament.
With every forehand and serve, the shoulder moves through forward motion stretching the posterior shoulder complex. Over time, through repetition and lack of posterior shoulder strength, the shoulder joint can become weakened and less stable. A myriad of injuries can occur from this point. Often, the rotator cuff becomes the first victim of injury. The root of the problem often lies in the substantial difference in the strength of the anterior shoulder complex vs the posterior shoulder complex. Weaknesses and imbalances in the posterior shoulder complex often result in inflammation of the muscles, tendons, or joints in the shoulder.
