From Russell Carleton at Baseball Prospectus on September 22, 2015:
A couple of weeks ago, I was listening to a podcast in which some French-Canadian guy whose favorite team doesn’t exist anymore was interviewing former major-league pitcher Mark Mulder. They were talking about the case of Matt Harvey and whether he should pitch in the playoffs, and the fact that no one really has any idea whether letting Harvey pitch so much after coming back from Tommy John surgery has any effect on his health going forward. Mulder and Jonah Keri got to talking about pitcher fatigue in general and the thought that tired pitchers were more likely to get hurt.
At one point, Mulder talked about how fatigue was more of a mental problem than anything. He described how, during his playing days, he might face a situation with runners on second and third with no one out, get out of the inning undamaged, but walk back to the dugout feeling totally exhausted. It wasn’t how many pitches he had thrown. It was the tension of the battle that got him.
I certainly can’t argue with Mulder’s lived experience. Throwing a baseball, like anything that requires physical exertion, is going to leave the body tired after a while. But tiredness is about more than just physical exertion. If you’ve ever had a day when you were nervous about something, and just sat around all day waiting for it to happen, you probably slept well that night. Someone who is nervous is in what’s known as a state of arousal. Many readers will be familiar with the idea of the “fight or flight” reflex that most animals, including humans, have. When the body is in this state of arousal, the body naturally gets all the key systems going. The heart pumps faster. The lungs breathe in more deeply. The muscle systems are primed for quick movement. The senses become more acute as the brain starts using extra resources as well. Eventually, the body needs rest.
Mulder probably also started being a little more careful in his delivery. He might have noticed a small mistake he made on the pitch before and made a point to correct it on the next one. There is no room to make a mistake in a runners-in-scoring-position scenario. So while a pitcher might rely on muscle memory in a different at-bat, now he finds himself thinking about the thing that he does with his left elbow. This might actually improve his pitches (or might not), but for something that is usually automatic and does not require a lot of thought, it suddenly becomes something that requires a lot of energy-draining pondering.
We know that pitchers generally lose some of their mojo as the game goes along and the pitch count climbs higher. But there’s something to be said for the idea that perhaps not all pitches are created equal. If a pitcher finds himself with a lot on his plate mentally, should his manager airlift him from the game a little earlier than he might otherwise?
Read the full article here (subscription required): http://www.baseballprospectus.com/article.php?articleid=27517
Originally published: September 22, 2015. Last Updated: September 22, 2015.