To better understand the interrelationship between release velocities and force and application time, let us assume some other numbers. When pitchers decrease their application time forces by five-hundreds of a second, the force required for pitchers to achieve ninety miles per hour release velocities increases to 8.8 lbs. Therefore, the application time directly influences the amount of force that pitchers have to apply to achieve their desired release velocities. The law of reaction requires that pitchers apply force toward second base equal to the force that they apply to baseballs toward home plate. If pitchers want to apply greater force to their baseball pitches, then they have to apply greater force toward second base.
Pitchers have three ways with which they can apply their oppositely directed force.
First, pitchers can push harder against the pitching rubber with their rear legs. Second, pitchers can push toward second base with their stride legs. Third, pitchers can use the inertial resistance of their body mass against which to apply oppositely directed forces. Against The Pitching Rubber Pitchers push against the pitching rubber with their rear legs to start their bodies forward. At one time, pitching coaches instructed pitchers to powerfully drive against the pitching rubber.