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The swing of the bat ... in the blink of an eye
By PETE GRATHOFFThe Kansas City Star
When he stops and thinks about it, Royals outfielder Mitch Maier is amazed that anyone can hit a home run.
“It’s crazy,” Maier said earlier this year. “Hitting a round ball with a round bat, moving 90 mph. It’s not always moving straight, it’s sinking or a curveball.”
Maier held two fingers about an inch apart as he continued: “You’re talking about hitting a sweet spot this big versus hitting the rest of the bat. That’s the difference between hitting it hard or getting jammed and having your bat breaking.”
Although we take it for granted, the science of the swing is an amazing thing to analyze. And it goes not just for hitting a home run, but for simply making contact.
Robert Adair, the author of the book “The Physics of Baseball” has studied the process in depth.
“You wonder why a guy who throws a 95 mph fastball is so much more effective than a guy who throws 90 mph,” Adair said in a phone interview. “It doesn’t seem like much difference. But when you add it all up, it’s a lot of difference.”
Here’s how Adair, who is Sterling Professor of Physics Emeritus at Yale University, breaks down the reaction time for a batter, who is facing a 90 mph fastball.
•LOOKING: It takes about 75 milliseconds (in the time the ball has traveled about 9 feet) from the first observation to the construction of the picture in the batter’s brain of the ball leaving the pitcher’s hand. This sometimes can be as much as 100 milliseconds.
•THINKING: The batter has about 50 milliseconds to decide if the pitch is a fastball, curve, slider or change-up and if it is too high or low or inside or outside. This time also can be slightly longer as a player makes minor mental adjustments.
•ACTION: The brain begins to send out the signals to the body that will be needed to make contact with the ball. About 15 milliseconds are needed for the fastest signal to get from the brain to the lower leg. Another 10 milliseconds are required to distribute the signals to the various muscle fibers through smaller and slower distribution axion-wires, each of which activates a set of from 10 to 1,000 muscle cells.
•BATTING: The swing of the bat takes 150 milliseconds or so. In the first 50 milliseconds, he can stop his swing, but after that it’s too late.
“The whole process just described, from the look at the pitch to the moment the bat crosses the plate,” Adair said, “takes about 300 milliseconds.”
The blink of an eye takes between 300 and 400 milliseconds.
“If someone didn’t know anything about baseball and added it all up,” Adair said, “they would come to the conclusion it was impossible to hit the ball.”
Yet it’s not — as the Yankees and Phillies have shown through the season. Adair said even before there was a thing called baseball, humans had to make quick decisions.
“Our prehistoric ancestors had to worry about what to do with a sabertooth tiger,” Adair said with a chuckle, “and those that didn’t do it very quick were eaten.”