This blog post will explain the principles and hidden secrets of how pitchers use scientific principles to throw a variety of change-ups.
I have had a special interest in professional baseball since I was young. At home, I was always wearing sweatpants and sliding down the slide, and I was often scolded by my mother. I also broke things while throwing a ball at the wall. Outside, I remember playing different sports with my friends depending on the professional sports season, and during the professional baseball season, I always played baseball at the playground. Now, I have fewer opportunities to play baseball as I did back then, so I watch baseball games to satisfy myself. When I was young, baseball was just about throwing, catching, hitting, and running, but now I think about the scientific elements hidden in it and anticipate numerous strategies.
How many people are aware that baseball is a very scientific sport? The saying “baseball is a pitcher’s game” is very famous. This means that if the pitcher is good, the team has a very high probability of winning the game. Conversely, no matter how strong the batting lineup is, if the mound is not solid, victory cannot be guaranteed. Teams with good pitchers often win, so the role of the pitcher is very important in baseball.
So what makes a good pitcher? Simply put, they are pitchers who make good use of science. The distance from the mound to the home plate is 18.44 meters. The time it takes for a ball thrown by a pitcher to travel this distance is about 0.4 seconds, which is the time it takes to blink once. Let’s take a look at what happens in this short moment.
There are many different pitches that pitchers throw. Starting pitchers have an advantage when it comes to winning the battle of the batters’ minds, the more pitches they have, the better. On the other hand, a closer, who is responsible for the last one or two innings of the game, needs a fastball that can overwhelm the batter. The most common pitches are fastballs, sliders, curves, and changeups, which many pitchers can throw. However, splitters, cutters, forkballs, knuckleballs, palmballs, rising fastballs, and slow curves are pitches that can be thrown according to the characteristics of each pitcher and are not common. The point to note here is that all pitches, except for the fastball, are change-up pitches. Even if you exclude the two-seam fastball, four-seam fastball, and rising fastball, all of the ten or more pitches fall into the category of change-up pitches. So how did such a wide variety of change-up pitches come about?
The secret lies in the 108 stitches on the baseball and the air resistance it receives. When the ball leaves the pitcher’s hand, it spins and receives air resistance. However, not all sides receive the same resistance. The stitched part of the baseball receives greater resistance. The trajectory of the ball changes depending on which grip the pitcher uses to throw the ball, that is, the direction in which the seam rotates. There is one law that must be understood to understand the changeup, and that is Bernoulli’s law. Bernoulli’s law defines the relationship between the pressure and velocity acting on a fluid, stating that the pressure decreases where the velocity of the fluid is high and increases where the velocity is low.
Let’s take a look at a curve, a type of changeup. A curve is a changeup that flies like a fastball but then sharply curves downward just before the batter swings the bat, that is, just before reaching the home plate. A scene in which a pitcher who mainly uses curves strikes out a batter with this pitch is one of the most exciting scenes in baseball. This is possible because the ball spins strongly from top to bottom due to the grip the pitcher has when throwing the ball. In other words, the upper part of the ball loses speed because the direction of the ball’s rotation and the direction of air resistance are different, while the lower part gains speed. According to Bernoulli’s principle, the upper part of the ball has higher pressure and the lower part has lower pressure, so the ball eventually curves from top to bottom. When this curve coincides with the moment when the batter swings the bat, the effect of the curve is maximized. This shows that the distance from the mound to the catcher’s mitt is precisely calculated.
All of the aforementioned various change-ups basically follow the Bernoulli principle. The slider is a pitch that changes the ball’s trajectory in the lateral direction with a different grip than the curve, and it is relatively easy to learn, so it is commonly seen in amateur baseball. Each of these pitches has a unique trajectory, and the grip used to induce them is also unique. However, there is one type of pitch that is clearly different from the others. It is the knuckleball. The knuckleball does not change the trajectory of the ball by rotating it in a specific direction like other pitches. It is a type of pitch in which the ball is thrown without using the wrist by inserting the fingernail between the stitches, and the ball is hardly rotated. This causes the ball to dance, making its trajectory irregular. In theory, since the ball is not rotating, it encounters great resistance regardless of its direction. As a result, the ball’s weight and the resistance of the air generate lift in any direction, causing the ball to fly in a direction that even the pitcher cannot predict. This weird changeup makes batters swing at pitches that are less than 100 km/h. Even the best catchers in the major leagues are flummoxed by it. This pitch is difficult to master and difficult to control, so very few pitchers can throw it perfectly.
Even if we exclude knuckleballs, would the ball of any pitcher be the same if he throws the same changeup with the same grip? There is one thing we should not overlook. Baseball is also a human sport. No two pitchers’ changeups are the same. Even if it’s the same slider, the pitchers’ balls will inevitably have different speeds, drops, and speeds. This can be simply explained by the difference in the abilities of pitchers, but the abilities of a pitcher include various external factors, not just the ability to throw a ball. Every pitcher has their own pitching form, and this pitching form makes the characteristics of the changeup different. In the end, since there is no standard for pitching form, pitchers must make an effort to equip themselves with the changeup that best suits them.
When it comes to change-up pitches, the amount is so vast that it is impossible to know the end of it, and a lot of research is actually being done on this. Even top pitchers do not know the grip of all change-up pitches, and it is difficult for them to throw any change-up pitch with confidence. This blog post was written to convey the knowledge I have naturally gained from my personal interest in baseball in an easy-to-understand manner. I think baseball is the most complex of all sports. But if you’re interested, you can learn about the various rules, strategies, and sports science behind it. In this article, I talked about the science behind the changeup pitch. But from the batter’s perspective, there is also the science of the body’s reaction to identifying the pitch within 0.4 seconds and reacting to it by recognizing that it is a strike. If you read this and watch a baseball game in the future, pay more attention to the changeup pitches of pitchers. It would also be a good idea to look up interesting data, such as the comments of commentators and the fact that changeup pitchers perform better in humid summers.
