Nearly 6 million U.S. children in eighth grade or younger play baseball. Unfortunately, the percentage of these athletes who will sustain an injury is ever growing. Pitch Volume, throwing mechanics, and shoulder range of motion are three major areas that influence risk of injury. As we approach the beginning of the baseball season, I would like to address preventive measures that athletes, their parents and coaches can take to reduce the risk of injury this season. In this two part blog series, I will first discuss stretches to increase shoulder range of motion and enhance throwing mechanics. In a follow-up blog, I will address pitch volume and its effect on injury risk.

The throwing shoulder of a baseball player goes through adaptive changes including increased range of motion in external rotation and decreased internal rotation compared to their non-throwing arm.

External Rotation

External Rotation

Internal Rotation

Internal Rotation

When loss of internal rotation motion exceeds gains in external rotation, a thrower is at greater risk for injury. Maintaining or improving internal rotation motion in preseason greatly reduces injury risk as the season ramps up. This can be done by stretching the posterior capsule with a sleeper stretch.


Another important motion for throwers is horizontal adduction or how far you can reach your arm across the front of your body. Loss of horizontal adduction has been shown to increases the risk of a throwing injury. Again, stretching is important to start in preseason to increase range, and continue throughout the season to maintain range.


Switching to the lower body, stride length impacts injury risk and has also been shown to improve performance. If a pitcher’s stride is limited during windup, excess force will be necessary at his elbow and shoulder to effectively throw. Stretching to increase hamstring, hip flexor, and hip adductor length can increase stride length, and should be performed with preseason training and after games throughout the year.


All stretches should be held for 30 to 60 seconds, done daily during the preseason and done following games during the season, and all leg stretches should be performed on both sides.

With proper preseason emphasis on increasing range of motion, and in season efforts to maintain motion, throwing athletes will reduce the risk of injury and improve throwing mechanics. For custom assessment and recommendations, visit a throwing specialist at Freedom Physical Therapy Services.