The concept of “Push vs. Pull” is central to the different teachings of the swing. Sir Isaac Newton determined that all movement is either a push or a pull. You can envision being at the ball park and seeing spectators pulling wagons with their chairs, coolers, etc. If you have ever pulled a wagon, you will notice how easy it is to keep the wagon moving in a straight line when you let it trail behind you. When you try to push it from behind, you develop a “zig zag” path, and the movement seems less stable.
When we look at the definition of the pulling motion, it is the act of moving something toward you, or toward a center. A push is the exact opposite. If you are trying to push a box across the floor, are you effectively moving it away from you, or toward you? The reason that the pulled wagon travels in a much straighter line is that the force acting upon it is always moving toward a centralized point. When you stand behind it and push it, it could move in any number of directions, a full 360 degrees away from center. When we apply this to the baseball swing, we can get away from out dated instructions, such as “keep your front shoulder in”. We would say pull your scap towards the spine.
The goal of the swing is to create centered rotation around the spine. The spine serves as a perfect axis around which to rotate in the swing. In the pulling of the wagon example, we were only talking about pushing and pulling as it pertains to the linear motion. The baseball swing is rotational, so Sir Isaac Newton also introduced centripetal and centrifugal force. Centrifugal force is a false force that is simply a result of centripetal force. The reality is centrifugal force doesn’t exist at all, and no object would continue rotating around a centralized point without the aid of centripetal force or gravitational pull. Rather, it would continue in a straight line. However, centripetal force is real, powerful, and efficient.
To really understand centripetal force, imagine a ball on the end of a string attached to a stick. By moving the stick in a very small circular motion, the ball on the end of the string can be accelerated to terrific speeds within minimal effort by you. Your tiny hand movements are creating centripetal force and are always pulling in the opposite direction of the ball to keep it moving at the highest velocities. The bigger you make your hand movements, the slower the ball begins to move, and the more effort you have to put into moving the stick to continue accelerating the ball. As part of these bigger movements, it also begins to become much more difficult to keep the ball orbiting on a constant plane. Upon reaching maximum speed, the string will naturally extend to 90 degree in relation to the stick, and the ball will travel on a single plane around the stick, as long as the stick remains centered and moving with the same simple, tight little movements. The looser the movement, the more difficult it becomes to keep the ball “on plane”.
It’s not hard to see how this analogy directly relates to the baseball swing. The key is that the plane is very easy to control using the concepts of push/pull and centripetal and centrifugal force.
Try standing upright and hold your bat tightly across your chest. From behind, have someone move you by pushing you from both sides of the bat. You will notice your head will move in both directions. Now have someone pull the end of the bat back behind you. You will notice how much easier it is to load and how much tighter and smaller the movement feels compared to pushing.
In the first image, when pushing from either side, the head moves away from the center, as does the rest of the body. For most hitters that is how they gather and load. They push the left arm across the body by pushing from the left side.
When being pulled, your head stays centered and the body can easily make a full load without moving off the ball. You’ll notice in the pull images that the head remains very centered. More importantly, you can feel this when your partner pulls you. The key is to create centered rotation around the spine.
Once we figure out why we want to pull, and the benefit of doing so, we need to look at how we create this rotation. This is where a basic understanding of anatomy comes in handy for the instructor. When doing the push/pull exercise, you had someone create the force for you by pulling or pushing on the bat. Now, your muscles need to create that same force. The first set of muscles that facilitate rotating the torso are the oblique’s. If you sit at the edge of a chair and begin turning your torso from side to side with some speed, you will become aware of your oblique’s. The second set of muscles are in the back. We refer to these as the lower trapezius and latissimus muscles. The lower trap and the rhomboid work to pull the scapula toward the spine during the load process, and when done properly you will feel your latissimus muscles activate.
Using the scapular motion of gliding it across the ribcage in toward center, helps create centered rotation, exactly like what we are looking for to get hitters to connect with the big muscles of their core. This movement is a key component for the hitter to create a pulling motion, which is necessary for an efficient centered rotation, which helps with a small and tight load and swing. When a hitter focuses his efforts on pulling, it is a new feeling for him. While he may feel the left oblique firing, the right oblique is also helping, as they work in pairs in rotating the torso. It is important for the hitter to feel pulling over anything else.
Pushing = Swaying
What I see a lot of kids doing, and what a lot of instructors are preaching, is to weight the back leg while pushing the hands back toward the catcher.
Same thing happens when you start the swing. Pushing the swing will cause the body to sway forward. Pushing moves the body around a lot.
Pulling = Toward Center
Instead, we want to activate the muscles that pull the swing. These muscles are going toward center, allowing you to make a nice centered turn. As you pull the right side back, you’re now activating the right side with your shoulder back as the point of activation.
As long as you are pulling in the swing, you’ll be working towards center. It’s when you start to push that you’re going to work away from center.