OVERHEAD PITCHING MECHANICS: THE KEY TO
Caleb Freeze, ATC, LAT
Pitching is a smooth continuous motion that happens over a brief period of time. During this time all segments of the body are used, starting with the legs during wind-up and ending with the hand and shoulder during release and deceleration.
Proper pitching mechanics is key to preventing injury in baseball pitchers. Understanding the four phases of the baseball pitch will be cornerstone of starting pitching program for young baseball players. These four phases are the wind-up, cocking, acceleration, and deceleration or follow-through.
Phase I. Wind-up
The wind-up phase of pitching allows the pitcher to develop a rhythm and balance. It is the least demanding phase of the pitching motion. In the wind-up phase the opposite leg is lifted significantly and the trunk is rotated toward the pitching hand side, creating potential energy for the pitch.
Phase II. Cocking
The cocking phase prepares the arm for acceleration by placing it into an extreme stretch. The cocking phase begins with the transfer of the ball into the throwing hand, and ends with the planting of the opposite leg into the ground. During the cocking phase the pelvis and trunk are rotated towards home plate and the shoulder and elbow are maximally stretched creating great potential force for the pitch. This stretching of the shoulder puts maximum stress on the front of the shoulder joint.
Phase III. Acceleration
The acceleration phase begins with maximum shoulder rotation and ends with the ball leaving the hand. During the acceleration phase the shoulder provides support for the "whipping" of the elbow and arm. Movement of the shoulder during acceleration is primarily internal rotation. The elbow moves from a flexed position of an extended position. The baseball is accelerated from 0mph to as much as 100mph during this phase and it is all done in a very short time.
Phase IV. Follow-Through
The follow-through phase is from the point the ball is released to the completion of the forward motion when the support leg contacts the ground to stop the forward body motion. It is during this phase the maximum stress is placed on the rear portion of the shoulder and injury can occur to this area. The deceleration forces are nearly two times as great as the acceleration forces on the shoulder.
The throwing motion is a progression of the larger body segments of the legs progressing to the smaller body segments of the arm and hand. Therefore while training, all muscle groups of the legs, torso, and upper body, including shoulder, bicep, triceps and forearm, should be emphasized for maximum performance.