Lack Of Pitch Recognition Affects Swing Mechanics

“Hitting is timing. Pitching is upsetting timing,” said the winningest left-handed pitcher in MLB history.  “A pitcher needs two pitches, one they’re looking for and one to cross them up.” Consistently crossing up hitters is what kept Warren Spahn in the big leagues for 21 seasons, amassing 363 wins including a Cy Young award and World Series championship in 1957 with the Milwaukee Braves, where he spent all but one season. To which Ted Williams is known to reply, “Hitting is 50% above the shoulders.”

It’s a Catch-22 at the plate; if a hitter doesn’t try to anticipate a specific type of pitch, he typically won’t be able to make a decision quick enough after release to make contact. But if he preloads an expected pitch into his brain, he has half a chance of being fooled. The necessary biomechanics to begin a swing take valuable milliseconds during the half second the ball is traveling to the plate.

If a batter is able to correctly predict the pitch type, his swing movement will be timed in unison with the pitcher’s throwing motion. Tomohisa Miyanishi and So Endo of the Graduate School of Sports Science at Japan’s Sendai University set out to actually measure the correlation of the mirrored movements.

“Previous biomechanical studies of baseball have investigated separately the pitching and hitting motions, and they have provided useful findings,” in the paper they presented at the 34th International Conference on Biomechanics in Sports in Japan. “However, an actual match-up between a pitcher and a batter forces the batter to predict what the pitcher is going to do before swinging the bat with correct timing to hit the ball successfully. There has never been a study that investigated the batting motion in an actual match-up against the pitcher.”

So, they designed an experiment to examine the changes that batters make to their swing kinematics when they are told the pitch type coming versus when they are not informed of whether the pitch will be a fastball or an off-speed pitch (curveball or slider). With nine college pitchers and nine hitters, they set-up motion capture cameras to record the synchronized motions of both during a pitch/swing sequence.

In Figure 1 below from the paper, each motion sequence is broken down into phases, so that the timing and duration of each segment can be measured and compared.

 Flgure I: Definitions of each phase for (a) the pitchlng and (b) the batting motions. Flgure I: Definitions of each phase for (a) the pitchlng and (b) the batting motions.

After recording and comparing the sequences across 185 pitches where the batter was told the pitch type, then with 185 pitches where no pitch tip was given, the researchers noticed a significant difference. Across the five different phases of pitching and hitting, including the total time, the two sequences were statistically correlated when the batter knew what was coming. This makes sense as the hitter knows the speed and trajectory of the pitch so can time his swing almost perfectly with the arrival of the ball.

However, when the pitch was unknown to the hitter, this paired timing was not seen.  

“Batting is probably more difficult in the unknown situation than in the known situation, and the unknown situation possibly makes the batter spend more time deciding how to hit the ball, which in turn forces him later to use an increased speed for the bat swing,” explain the researchers. “In other words, in contrast with the known situation, in the unknown situation the batter waits a relatively long time to hit the ball, until the ball is close to the batter, and then uses greater rotation speed of trunk and bat.”

In fact, this hesitation causes a big change in swing mechanics as the legs and trunk have to hold back until the last possible millisecond while waiting for instructions from the brain.

“Thus, controlling the bat not with the legs but with the arms would be important in order to address the pitched ball in the unknown situation,” wrote the researchers.

By training pitch recognition skills, hitters gain back those milliseconds so their swing can maximize rotation and bat speed, not to mention accuracy of contact. By first anticipating a pitch type from the game situation, then confirming their guess with early visual perception, their mechanics can remain consistent.

Dan Peterson is a writer/consultant specializing in the cognitive skills of athletes.