Dispelling The Mystery of Pitch Speed
July 23, 2015 | Abbi Nicolella
@ChiCityBrian @enosarris If I said that, I misspoke. 1 mph pitch = 0.2 mph exit=
1 ft distance. 1 mph bat = 1.2 mph exit= 6 ft distance.— Alan Nathan (@pobguy) July 14, 2015
PITTSBURGH – In the midst of our Science of Baseball conversation with Dr. Alan Nathan during the Home Run Derby, a simple but astute question was posed.
“How much does pitch speed effect the distance a ball travels?”
The thought behind the question being, “If MLB players are hitting the ball 440 feet during the Home Run Derby with grooved batting practice pitches going roughly 70 mph or so, how far could they hit the ball if they had a grooved 90 mph pitch?”
After some clarification, Dr. Nathan responded with the Tweet you see at the top of this post.
Case seemingly closed.
But last week, in response to Dr. William Clark’s article on Momentum in Baseball, a reader made a remark that velocity of a pitched ball and rotation has a lot to do with exit velocity, and then later referenced Newton’s Third Law.
Velocity of a pitched ball and the rotation has a lot to do with exit velocities as well. http://t.co/tJS9CbTz9o
— Brian Jordan (@BrianJordan303) July 17, 2015
@DiamondKinetics So, the speed of one of the two objects doesn’t matter as much?? (Bat vs. ball) How is that?
— Brian Jordan (@BrianJordan303) July 17, 2015
@DiamondKinetics Newton’s Third Law would imply that both velocities are important when they interact. Bat speed and pitch velocity.
— Brian Jordan (@BrianJordan303) July 17, 2015
This reader seemingly could not grasp the science involved in the ball to bat collision, so we are here – with the help of Dr. Nathan – to dispel the mystery of pitch speed, relative to exit velocity and distance a ball travels.
Question: why aren’t people normalizing batted ball speed for the incoming pitch speed
— THIRSTY LOON (@dj_mosfett) July 16, 2015
@dj_mosfett they probably should but Alan Nathan said pitch speed doesn’t have a huge effect on exit velocity
— Scott. (@OdinsBeard) July 16, 2015
@OdinsBeard @dj_mosfett really? Link? That goes against my completely unfounded thoughts
— Butt Outlet (@AGremlinStorm) July 16, 2015
@AGremlinStorm @dj_mosfett you could ask @pobguy but I think he said a 10 mph pitch velocity difference means ~2 mph exit velocity diff.
— Scott. (@OdinsBeard) July 16, 2015
@OdinsBeard @AGremlinStorm @dj_mosfett Plot from HITf/x . Note the 4 mph shift in exit for 20 mph shift in pitch. pic.twitter.com/i3kYLv46KF
— Alan Nathan (@pobguy) July 16, 2015
I do not understand the concept of “generated velocity”. All of the exit velocity is ‘generated’ by the hitter. https://t.co/impeZtHV0M
— Rob Arthur (@No_Little_Plans) July 16, 2015
@No_Little_Plans @statcast with you on this one. Have wondered the point of this arbitrary measure all season. Maybe @pobguy has insight?
— Brian Mills (@BMMillsy) July 16, 2015
@BMMillsy @No_Little_Plans @statcast Roughly 85% of exit speed comes from bat speed, rest comes from pitch speed (bunt~17 mph).
— Alan Nathan (@pobguy) July 16, 2015
as @pobguy has said, the speed of the pitch going in has relatively little effect on the speed going out, so why use the delta?
— Rob Arthur (@No_Little_Plans) July 16, 2015
Dr. Nathan also explained during our Science of Baseball conversation that while each mph of pitch speed adds 1 ft. to the distance, each mph of bat speed adds 1.2 mph of exit speed.
Since exit speed matters a lot, then bat speed matters a lot. Each mph of bat speed adds about 1.2 mph to exit speed. #PoBGuy
— Diamond Kinetics (@DiamondKinetics) July 14, 2015
Useful rule of thumb: Each mph of exit speed adds ~5 ft to typical HR trajectory. Optimum launch angle 25-30 degrees. #PoBGuy
— Diamond Kinetics (@DiamondKinetics) July 14, 2015
Finally, if you still aren’t convinced that pitch speed isn’t a huge factor in exit velocity, we have this Giancarlo Stanton home run from 2012 in which Stanton hit the scoreboard at Marlins Park after annihilating a pitch from Jamie Moyer.
Stanton’s exit velocity on this home run was 122.4 mph on a pitch from Moyer that was 66.4 mph.
Still think pitch speed matters that much?
