TORQUES AND FORCES PRODUCED DURING PITCHING
The pitching motion is a complex compilation of motion at the trunk, shoulder, and elbow that has effects on the entire upper extremity kinetic chain. Biomechanical studies have thoroughly investigated the angles, velocities, forces and torques that are present at the elbow and shoulder during the pitching motion. Subtle differences in mechanics (eg: onset of trunk rotation, maximal shoulder external rotation, elbow flexion at ball release) have been shown to produce differences in the torques and forces experienced.
To rotate a body segment, an athlete applies a torque, or angular force at a joint. The amount of angular acceleration of a body segment caused by an applied torque is inversely related to that segment's moment of inertia, or the segment's resistance to rotation. For any given muscle torque, the greater the mass of a segment and the farther that mass is distributed away from its rotational axis, the greater that segment's moment of inertia. In throwing, the lower extremity, pelvis, and trunk are the larger segments that produce the muscular torques that accelerate the smaller distal segments. These base segments have greater moments of inertia meaning they exhibit smaller angular velocities as they rotate. The smaller distal segments have smaller moments of inertia, but move with greater angular velocities.
To rotate a body segment, an athlete applies a torque, or angular force at a joint. The amount of angular acceleration of a body segment caused by an applied torque is inversely related to that segment's moment of inertia, or the segment's resistance to rotation. For any given muscle torque, the greater the mass of a segment and the farther that mass is distributed away from its rotational axis, the greater that segment's moment of inertia. In throwing, the lower extremity, pelvis, and trunk are the larger segments that produce the muscular torques that accelerate the smaller distal segments. These base segments have greater moments of inertia meaning they exhibit smaller angular velocities as they rotate. The smaller distal segments have smaller moments of inertia, but move with greater angular velocities.
ELBOW/FOREARMTORQUES: There are 2 main torques applied to the elbow and forearm: flexion torque and varus torque
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SHOULDERTORQUES: The torques applied at the shoulder are abduction torque, horizontal adduction torque, and internal rotation torque
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