Sarris: How body size is related to baseball power

From SABR member Eno Sarris at FanGraphs on April 24, 2015, with mention of SABR member Alan Nathan:

From the standpoint of physics, muscle begets bat speed, which begets power.

That part is simple, as physicist Alan Nathan has shown. “A 10% increase in muscle mass can lead to about a 3.8% increase in bat speed,” Nathan found, and that sort of bat speed increase can lead to an increase of 4.3% in batted ball distance.

And so this year, Mariners shortstop Brad Miller decided to put on more weight. Was it about the power? “Oh yeah. I want to get as physical as I can,” Miller admitted before a game with the Athletics this year. So he put on 15 pounds in the offseason and came into the season weighing 220, instead of the 205 he weighed to finish the season in 2014.

We don’t have yearly heights and weights for players, but we do have *a* listed height and weight for each player. Despite being of dubious quality, let’s see how Body Mass Index is related to power factors. Turns out, it is significantly related to many power stats, with Home Runs per Fly Ball providing the cleanest look.

Read the full article here: http://www.fangraphs.com/blogs/brad-miller-puts-on-weight-results-to-be-determined/



Originally published: April 24, 2015. Last Updated: April 24, 2015.