Body Types by Lineup Position – Visualized

On April 2nd, 2014, just one day removed from April Fools’ Day, the Houston Astros turned in the lineup for their game against the New York Yankees. Dexter Fowler would bat leadoff, Matt Dominguez would hit second and Robbie Grossman would bat in the three hole. The cleanup spot would be filled by Jose Altuve. Altuve is listed at five feet, five inches tall. Since that fateful day on April 2ns, he is now tied with Freddie Patek as the shortest player to bat cleanup since 1974.

Here comes the caveat that the Astros are doing their own thing at the moment and what they do should not be seen as some sort of new-age thinking in regards to winning baseball games. Short dudes in the four hole are not the new market inefficiency. Altuve’s odd lineup placement is just a phase. Like that one weird cousin of yours, Houston is taking some time to figure some stuff out right now.

Nevertheless, the Altuve bit isn’t without some sort of interest. Baseball — and most sports, really, tend to fall into tropes regarding certain types of players and what they should look like. Russell Wilson was thought to be too short to be an NFL quarterback. Kevin Durant is so long and lanky that he doesn’t look like he’d be such an fluid attacker of the basket. And Jose Altuve certainly doesn’t fit the mold of a power-stroking big-bopping cleanup hitter.

This all got me to wondering — baseball is, at its core, a skill game. Size and strength can certainly help, but it’s not a game that is dominated by the big and brawny. If that were the case, Altuve’s teammate Chris Carter would lead the league in everything. But that’s the nature of most other sports. Basketball players are getting bigger. Football players are certainly getting bigger. So what about baseball players? Are they falling in line as well?

I looked at the height of every batter who ever had a plate appearance since 1974 and averaged the heights out by year– well, I made a computer do that because I’m not a crazy person. I chose 1974 because that’s the earliest we here at FanGraphs have reliable player info for this type of thing. All of this info is weighted, so the Altuves of the world wouldn’t skew the numbers. Let’s zoom out first, and look at how player heights have evolved over the years.

I should probably throw in a disclaimer first. Yes, these numbers aren’t wholly accurate. I don’t know if it’s the players or the teams, but many guys are listed taller than they actually are. For the sake of argument, I’m assuming that most tend to lie at about the same rate, so while the actual numbers might be a little skewed, the changes between the two should stay consistent.

There was certainly some evolution early on (or perhaps less grandiose fibbing in the early days), but player heights have kind of leveled out since the early 1990s. There is a little vacillation there, but it happens within the realm of a half of an inch. All in all, at least as far as hitters go, the guys getting the most at bats have stayed about the same size for the past 25 years or so. But while they may not be getting much taller, position players are getting … wider.

Body mass index — or BMI — is a fairly rudimentary method to “weigh” a persons weight based on their height. It’s basically one’s mass divided by the square of one’s height. This chart is fairly self-explanatory. Baseball players used to be skinnier, then they got surprisingly bigger in the mid-2000s (sarcasm!), then they slimmed down a bit. They are still much bigger than they were 40 years ago, but it has seemed to die down from the muscle-bound craziness of a few years ago. Joking aside, this makes quite a bit of sense. As physical fitness training and technology get better, it seems logical that athletes would start packing on more muscle. It could be that players are just getting fatter, but I find that hard to believe. Until MLB starts taking body fat measurements along with height and weight we’ll never no know. But it seems fairly safe to assume we’re talking more about muscle that flab.

If we zoom in to a batting-order level, we can see how both of these measures hash out on a more granular scale.




Historically, the guys batting cleanup have been the biggest. It’s harder to tell if large hitters are better at batting cleanup or if they were just perceived that way and given more PAs in that spot. That might deserve some more research. The graphs are filterable, so you can click around and play with the data a bit. It’s interesting to see how some lineup positions level off fairly quickly while others like the 3rd spot suffered a bit of volatility over the years. Again, we’re dealing with inches and halves of inches, but it’s still of consequence considering the sheer amount of plate appearances involved.

George Springer is now in the big leagues, and soon Jon Singleton will be too. The days of the diminutive Altuve batting cleanup for the Astros are probably over. But his participation in the big-man position can help us understand just how flat player heights have been throughout the years. While pure physical dominance might help one reach the quarterback quicker grab a few extra rebounds, a simple size advantage doesn’t necessarily make a baseball player better. There’s still that whole tricky thing revolving around hand-eye coordination, it seems. Perhaps being 6’6″ makes one a better linebacker than someone who is 6’2″. But if being huge doesn’t help a player recognize breaking pitches or go the other way to beat the shift, then perhaps size doesn’t matter. The numbers certainly suggest that.