The Stride Drill is designed to train a pitcher's body to get into the proper throwing position enabling him to maximize velocity while minimizing the risk of injury during game situations.
This drill can be performed without a baseball and can be done individually by a pitcher if a throwing partner is not available.
First, let's take a closer look at the stride phase of the pitching motion.
A pitcher's should stride approximately 90% - 100% of the length of his height towards home plate during his fastball delivery. On the curveball and change-up, some pitchers will shorten up their stride by as much as 6".
Keeping the lower body aligned in a straight line closes a pitcher's hips, directs the shoulders, and allows the throwing arm to reach the "high cocked phase" of its arm path in the back of the pitcher's body.
If a pitcher lands too far to the glove-side of his body, he will open the shoulder too soon. This causes the pitch to be low and outside while creating stress on the arm and reducing velocity.
If a pitcher lands too far to the throwing-side, he will inevitably have to throw across his body making the outside part of the strike zone difficult to hit.
To begin, have the pitcher stand perpendicular to a straight line (like a foul line in the outfield grass or line on a gym floor). If the pitcher is on the pitching mound itself, he can use his spikes to drag out a straight line in the dirt 8-feet long and perpendicular to the rubber.
Then, he simply marks out the distance of his height and drags out a second line in the dirt--only this one is parallel to the pitcher's rubber.
The pitcher then goes through his entire delivery (with or without throwing the baseball at the end of the motion) and looks to see where his front foot lands in relation to the two lines he has etched out in the dirt. He can use either his full or set wind-up in this drill.
Did the pitcher land the length of his height? Did the pitcher stride in a straight line toward his target? If not, a pitcher should perform this drill until he has mastered his stride.