There is lots of information out there about the rotator cuff in respects to baseball but here it the number one thing everyone should know:  THE ROTATOR CUFF’S MAIN JOB IS NOT TO THROW A BALL BUT TO CONTROL THE JOINT WHILE THROWING AND STOP THE ARM AFTER RELEASE. 

Knowing this very important piece of information helps support the reasons why lots of injuries occur when the arm is fatigued or worn down overtime.  The muscles that make you throw a ball are large, consisting of the chest and back muscles.  These muscles are not likely to wear out, as they are the ones used for pull ups, swimming, bench pressing, or push-ups.  BIG MUSCLES!!  The muscles that stop the shoulder are much smaller and fine tuned.  There are more analogous to the fingers that play the piano, making fast and delicate movements to make beautiful movements.   

Knowing this, if the rotator cuff muscles get tired and cannot control the big muscles in the chest and back, the result is the rotator cuff gets hurt.  And when that group of muscles does not work, it doesn’t matter how hard you push the shoulder will not throw a ball.

So the take home is this: Pushing past the point of fatigue with throwing is gambling with body parts.  There is very little to win and a whole bunch to lose.