Guest post: Researchers, players disagree on optimal baseball bat weights

Photographs of Babe Ruth often capture the slugger gripping a bat, if not two, that resembles a troll’s club in length and thickness. With such a mass of lumber, one is tempted to think, it’s no wonder the guy hit 714 home runs.

But according to physicists, heavy bats can be detrimental to a player’s swing. One study, based on the calculation of bat speed, estimates that the average professional baseball player should swing a 31.1-ounce bat and the average college baseball player a 29.4-ouncer, but players at both levels often drastically exceed those guidelines.

Heavy bats, in fact, are ingrained in baseball lore.

Early-20th century star Frank “Home Run” Baker used a 52-ounce bat, according to Baseball: The Biographical Encyclopedia, and the Louisville Slugger company once sold bats weighing more than 45 ounces to many players, including eventual Hall of Famers Baker and Edd Roush.

But the end of the Deadball Era in the 1920s led to an emphasis on power over contact and an influx of lighter bats, according to P.J. Shelley of the Louisville Slugger Museum & Factory.

Then came Hall of Famer Ted Williams, a student of the game and one of history’s greatest hitters. Shelley says Williams, who mostly ordered bats between 32 and 34 ounces during a career that lasted from 1939 to 1960, was “one of the first to recognize that bat speed is more important than the weight of the bat.”

From Williams until about 25 years ago, bat weights dropped further, and today’s average Major Leaguer swings about 31.5 or 32 ounces, according to Shelley.

Though most players now use lighter bats than their predecessors, some still believe the more mass the better. According to Shelley, the Los Angeles Angels’ Josh Hamilton and Los Angeles Dodgers’ Hanley Ramirez swing 34.5- or 35-ounce bats, among the heaviest in the Major Leagues. And one Chicago Cubs player recently made headlines for his weighty bat choice.

In June 2012, Chicago Cubs left-fielder Alfonso Soriano was persuaded by manager Dale Sveum to pick up a 32-ounce bat, after years of using a 33.5-ounce behemoth, according to the Chicago Sun-Times.

“He’s typically used one of the heaviest bats in baseball most of his career,” Sun-Times reporter Gordon Wittenmyer said. “And you could make a case that’s part of his high-strikeout total, and it’s definitely part of his home run totals.”

Research supports Sveum’s suggestion that Soriano swing a lighter stick: In 1995, Terry Bahill and Miguel Morna Freitas of the University of Arizona developed a model that used bat speed to calculate ideal bat weight for any given baseball player. They also developed a simpler version using height, weight and age to estimate the optimal weight. According to the latter model, Soriano, at his listed height of 6 feet 1 inch, should use a 31.3-ounce bat, which, according to Bahill, would increase his contact rate.

“The 31- and the 33-ounce bat wouldn’t make a lot of difference in the distance the ball would go,” Bahill said. “But we think he could swing it more accurately if it were smaller.”

According to the Arizona duo’s study, the average college baseball player is best off with a 29.4-ounce bat, but Northwestern University baseball coach Paul Stevens said options are limited and most players use either 30- or 31-ounce bats.

NU shortstop Trevor Stevens is listed at 5 feet 9 inches, suggesting he should, according to Bahill’s model, swing a 29-ounce bat. But the switch-hitter uses a 31-ounce bat when he bats left-handed and a 30-ounce bat when he bats right-handed. He said those weights reflect what manufacturers produce and therefore what college players can access.

“There are bats that are weighted differently within the barrel and the handle,” Stevens said. “They feel lighter in your hands, but the ball doesn’t jump off of them as much.”

Stevens was referring to “moment of inertia” (or “swing weight” in baseball parlance), a parameter that measures the distribution of mass along the bat. Dr. Daniel A. Russell of Pennsylvania State University said a number of studies have proven moment of inertia more important than bat weight in bat choice.

“It’s not just how heavy the bat is, it’s how that weight is distributed,” Russell said. “You can take two bats that both weight 30 ounces and you’ll get very different behaviors depending on how the weight is distributed.”

Despite the available research, Wittenmyer said he has never heard anyone around the Major Leagues reference any studies on bat choice, suggesting the choices players make when choosing their equipment is more instinct than science.

Unscientific thinking may be advisable given the imprecision of the researchers’ conclusions. Bahill said his simplified model can only predict ideal bat weight within about two ounces and in order to get precise results, a player must come into his lab for measurements.

Hence what Shelley calls the true determinant of bat choice among baseball players of all ages.

“It’s a matter of player preference,” he said. “And what feels comfortable to them.”

The Bat Chooser: In 1995, Terry Bahill and Morna Freitas developed a method for choosing the right baseball bat, appropriately dubbed “The Bat Chooser.” This model calculated maximum bat speed using the force generated by a players swing and measured subjects across all levels of play. Because the original Bat Chooser required players to visit a laboratory for precise measurement, the researchers simplified their model to estimate ideal bat weight using height, weight and age. Later research brought into question the validity of these calculations.

Mean ideal bat weight of those studied (oz)

Number of subjects studied

Professional, major league



University baseball



University softball



Junior league, age 13-15



Little League, age 11-12



Little League, age 9-10



Little League, age 7-8



Slow pitch softball




Recommended Bat Weight (oz)

Professional, major league

Height/3 + 7

University baseball

Height/3 +6

Fast pitch softball

Height/7 + 20

Junior league, age 13-15

Height/3 + 1

Little League, age 11-12

Weight/18 + 16

Little League, age 9-10

Height/3 + 4

Little League, age 7-8

Age*2 + 4

Slow pitch softball

Weight/115 + 24

Age (years); height (inches); weight (pounds)

Announcing a new policy at BPP: Paid guest posts

There’s something I’ve been mulling for some time now that I think needs to be said. I’ll try to keep this brief.

I’ve reached the point in my writing career where I only want to do paid work. My ultimate goal is to make a living as a writer, preferably a sportswriter. I worry that the longer I do free work, the more I sell myself short and belabor this goal. It’s part of the reason I haven’t written a ton here over the past several months.

I deserve to be compensated for what I do. All writers should. I understand that the Internet is a still-evolving medium as well as a meritocracy and that web publishers are still figuring out ways to make paid content work. That said, I believe we can and should help each other.

Effective immediately, all guest posts at this website will be paid. I’m coming out of pocket, so I can afford to do this a maximum of once a month and pay $25 per piece. (I can’t yet pay for participation in group projects, though I’m happy to offer trade: You write for my project, I’ll write for yours.) As advertising dollars increase, I’ll try to up the volume of paid content and the amount I pay per piece.

I believe paying for content is the right thing to do from an ethical, altruistic and karmic standpoint. I simply no longer feel right accepting free work while asking payment for what I do.

On a related note, I solicited donations for charity a year ago promising a free set of trading cards to anyone who donated at least $25 to said charity. I finally have money to print these cards. I have a list of donors who I’ll soon be reaching out to. If you remembered donating $25 and would like a set of cards, please email me at

An open letter to Bill Dwyre

Dear Bill Dwyre,

My name is Graham Womack. You probably don’t remember me, but I attended a sports journalism workshop you helped put on in 2003 as sports editor of the Los Angeles Times. I was one of 30 college students selected from around the country to spend a few days at Hollywood Park horse racing track leading up to the Jim Murray Classic. It’s hard to believe as I look back but that workshop was my first exposure to Murray’s writing; a decade on, the greatest sports columnist ever (and it’s not even close) remains a significant influence for me. I also got to hang out with a bunch of other talented, aspiring journalists and rub elbows with a few working writers. Best of all, I think everything was free.

So it was with disappointment that I read your recent column, Angels’ Jerry Dipoto speaks to the SABR rattlers. I’m not the first person to speak out regarding your rant against sabermetrics. Former LA Times staffer Matt Welch posted a rebuttal on Friday evening that’s worth a read if you haven’t checked it out already. I was alerted to your column after another writer tweeted on Saturday that your piece might be the worst baseball article of 2013. I wouldn’t go that far. You’re certainly not the first journalist I’ve come across with little use for advanced baseball statistics. Heck, I feel like I read this type of column every few months and generally I don’t respond. I’m making an exception this time, in part because the group you bashed, the Society for American Baseball Research, is about so much more than sabermetrics.

I’m in my third year as a SABR member. I don’t speak for SABR or have its demographics onhand, but in my experience, we’re primarily baseball history enthusiasts. Honestly, we’re people who know entirely too much about baseball history: that the 1926 World Series ended because Babe Ruth was thrown out stealing; that Joe DiMaggio barely missed having more homers than strikeouts in his career; that Smoky Joe Wood, Denny McLain and Dwight Gooden all had more wins before their 25th birthdays than after. I’ve been reading about baseball history since I was eight. For much of my life, the knowledge I’ve accumulated has been of little use to those around me, a curiosity mostly. At SABR meetings, I’m around peers, many of whom know more than I do. I feel at home. By the way, SABR predates the term “sabermetrics” by about a decade. There’s no official connection between the two terms. Most SABR members aren’t sabermetricians, I’d venture.

Is some of SABR’s membership zealously into advanced stats? Sure. The event that you got your column from attending, the annual SABR Analytics Conference in Phoenix attracts this cross section. The registration alone for this conference was $495 with a member discount. I contemplated going because a bunch of prominent baseball writers were scheduled to attend and I’d like to be acknowledged for knowing basic sabermetrics. I’d also like to learn more. I decided against going, as I didn’t have the money and I’m no hardcore statistician. Anyhow, I have other things on my baseball bucket list that I might splurge on first. I want to attend the main SABR conference in Philadelphia in July. I’d like to do a research trip to Chicago and catch a game at Wrigley Field while I’m there. I’d also like to make another visit to the Hall of Fame, possibly when 19th century great Deacon White gets inducted this summer. I know I’m not the only member who thinks this way.

So we’re clear, I embrace sabermetrics. I didn’t a few years ago– like you, I once joked about the meaning of VORP– but after I began writing often about baseball, I found that basic advanced stats improved my understanding. The story side of baseball history was and is my primary love. But I like being able to rely on something besides quotes and opinions to tell stories. I’ve read of Casey Stengel bemoaning one of his outfielders driving in a run but letting three more in with shoddy fielding. I like that there’s a way to quantify this with metrics such as Wins Above Replacement that assess a player’s total value, taking all facets of his play into account. I like OPS+ and wRC+ that compare a hitter’s production to league average, normalizing for ballpark and era. For me, so much about baseball research is establishing context. While I don’t think sabermetrics alone can do this, they’re a valuable part of the equation.

That being said, I think the majority of SABR members hold true to traditional stats like batting average, runs batted in and pitcher wins. Jack Morris’s Hall of Fame case is a source of continual derision among many sabermetricians, as Black Jack has underwhelming ratings for various advanced stats; I read somewhere that more than half of SABR members support Morris being enshrined. At a SABR meeting in January, I took in a presentation from a fellow member who talked about flying to libraries around the country to look through old newspaper records to doublecheck long-ago RBI totals. I personally think RBIs are a misleading indicator of player value, since they’re dependent on a number of factors outside a hitter’s control. I rose my hand to ask this fellow why he wasn’t putting all this (commendable) effort into researching another stat. He tersely replied something to the effect of, “Well, you know, runs decide games.” I don’t know if people like this fellow would ever attend SABR Analytics. I suspect not.

I’m sorry you got the wrong idea about SABR, near as I can gather from reading your column. I invite you to give my organization another shot in the future. Perhaps the Allan Roth Chapter in Los Angeles could have you speak at a future meeting. Beat writers, broadcasters and other media members are common fixtures at meetings. I imagine you have loads of great baseball stories that a lot of us would love to hear.

Regardless, I close respectfully.

Graham Womack