Pitching Mechanics and MLB Hitter Reaction Times

Jered Weaver threw a no-hitter on Wednesday night. Weaver has been a really good pitcher for the past several seasons, so the fact that he threw a no-hitter, against the Minnesota Twins, is not too surprising (although still an incredible accomplishment). During his no-hitter, Kevin Goldstein tweeted the following “Jered Weaver’s ability to manipulate a baseball is remarkable. Guys with that stuff and that arm angle should not be THIS good.” This re-invigorated me to research something that I have wondered about for a long time – what impact does a pitcher’s height, release point, and ability to hide the ball have on the hitter’s chances for success?

The underlying impact of all three of these variables is the change in a hitter’s reaction time. You’ll see some times later in this post, but MLB hitters have an otherworldly small amount of time to see a pitch, start their swing, and make solid connection using a round bat moving approximately 72 mph on a round ball moving in the opposite direction at approximately 90 mph. If a pitcher can manipulate a hitter’s reaction time to be even shorter by taking advantage of height or pitching delivery, the impact is far-reaching on every one of that pitcher’s pitches, not just the fastball. The hitter has precious fractions of a second to attempt to hit a pitcher, and if a pitcher can steal even a few of those milliseconds from the hitter, the pitcher’s chance of success can only increase.

Let me begin my detailing some assumptions that I have made. First, it is difficult for me to provide a precisely accurate release point for a pitcher based on his height. I have made an estimation for release point in the following manner: I have assumed that the length of a man’s leg is 53% of his height (I’m 73 inches tall, my inseam from floor to crotch – I really wish there was another word for crotch – is 39 inches long, and I feel I’m proportionally representative of an average person, #humblebrag). Next, I have assumed that at release, a pitcher’s plant leg is bent to be half the height of his leg when fully extended. Using these two pieces of information, and the Pythagorean theorem (look, Mom, I’m using trigonometry!), we can determine an approximate distance from the pitching rubber that a pitcher releases the ball. See the below picture for the illustration:



Now, we’ll get to the data. Get your spreadsheet-reading goggles on.

I created these tables with three variables that can be changed to generate different results: Pitcher height, ball hiding (using a -6 to +6 in. scale), and pitch speed. In this first table, I have held pitch speed constant at 90-mph, and ball hiding constant at 0 (average), and have adjusted the pitcher’s height by 1 in., starting at 5’10”, and increasing to 6’10”.


First, notice the time a pitch is visible from on a 90-mph pitch from a 5’10” pitcher, which is a very average fastball from a very short pitcher. The batter still only has .4379 seconds to see the ball. On top of that, I’m assuming the hitter has to make his decision to swing approximately when the ball is halfway to the plate, leaving him only .2189 seconds to see the pitch and decide to swing. Just imagine how brief that instant is before that decision has to be made. Truly, stop and think about it. It took you longer to read “point-two-one-eight-nine seconds”, than it does for a hitter to decide he has to swing at a below average MLB fastball.

Now, look at the change in reaction time based on a pitcher’s height. Adding one inch to a pitcher’s height changes the time a ball is visible by 0.0003 seconds. While you don’t yet know how this compares relative to the other variables, I can assure you that this isn’t very much, unless you look at the difference between the 6’10” pitcher and the 5’10” pitcher, in which case the visible time is 0.0035 seconds less. This is more significant.

In the next table, pitch speed is held constant at 90-mph and the pitcher’s height is held constant at 6’4”, which seems about right for the average MLB pitcher. The only variable is the change in when a ball becomes visible to the hitter.



As you can see by the hitter’s reaction times, the point at which the ball becomes visible to the hitter has a larger impact than the height of a pitcher, as a one inch change in visibility results in 0.0006 seconds less visible time. Again, this is difficult to measure, as it is more an arbitrary statement made about pitchers that “he hides the ball well”. Weaver is among the best in the league at hiding the ball, due to his unconventional, extreme cross-body delivery. Two examples of Rangers who hide the ball well are Yu Darvish and Alexi Ogando. The two .GIFs below show each pitcher getting a strikeout on a breaking ball that fools the hitter badly. The hitters are out in front, likely looking fastball, but because of their reduced ability to recognize the pitch early, are caught off balance and whiff harmlessly.



Finally, we come to the third variable: pitch speed. Holding pitcher height and release point constant, here are the changes in reaction time based on tweaking pitch speed in 1-mph increments.


Not surprisingly, pitch speed has a significantly larger impact on hitter reaction time than the other two variables, with a 1-mph speed change having an average impact to visible time of 0.0045 seconds, over 4x more of an impact than release point. Speed is still king, in this regard.

There are so many variables to pitching, and just isolating these three doesn’t paint the whole picture. The movement on pitches, the sequence in which they are thrown, the hitter’s preference to a pitcher’s style, and the platoon matchup are all extremely significant. But this at least gives you a taste of the impact of a pitcher’s size, mechanics, and pitch speed on the hitter. One last table for you, which shows what I estimate Weaver’s three inputs for these variables are. Weaver is 6’7”, averages a 90-mph velocity on his fastball, and I am giving him the best rating for release point.


The result is a visible time of 0.4315, which is equivalent to a 91-mph fastball from a 6’4” pitcher with an average release point. So while this doesn’t fit with those who say that when Weaver pitches, “it looks like 95-mph” to the hitter, but you can see that his mechanics and size do give him an advantage in hitter reaction time a full MPH above what the radar gun says.

Peter Ellwood is a Senior Staff Writer for Shutdown Inning. You can email him at Peter.Ellwood@shutdowninning.com or reach him on Twitter @Peter_Ellwood

Peter Ellwood

Leave a Reply