The parallels between a baseball’s performance and science as it relates to STEM Baseball Curriculum

‘Best baseball I’ve ever touched’: Why players love Japanese Olympic baseballs

This article was originally published by the Los Angeles Times

YOKOHAMA, Japan — The baseball tournament at these Olympics has featured bigwigs from yesteryear, prospects on the rise and Asian stars in their primes. There have been exciting introductions and emotional goodbyes, thrilling finishes and gloomy heartbreak. But the star of the show might be the most prevalent, under-the-radar component on display every day: the baseball.

“They need this ball over in America,” said Joe Ryan, a starting pitcher for the United States. “It is amazing. It’s perfect.”

The baseball used in the major leagues, according to seemingly every pitcher you ask over there, is far from perfect. It’s slick. It’s inconsistent. It’s a problem. So much so that it became accepted for pitchers to use illegal foreign substances for better grip in recent years until Major League Baseball, after negative public comments from players, determined the cheating crossed a fuzzy line.

The substances allowed for unprecedented spin rates, which increased pitch movement and made hitting more difficult. Strikeouts, subsequently, steadily rose to historic levels in recent years. MLB determined the pattern was hurting its product.

In March, before the regular season started, MLB sent a memo to teams communicating plans to implement increased monitoring of baseballs and to crack down on the use of foreign substances. But the league stopped short of saying it would punish pitchers. That quickly changed.

In June, the league announced it would regularly check pitchers for substances in games and eject and suspend pitchers caught with sticky stuff for 10 games. The timing — midseason with little time to adjust — drew scorn from pitchers. At least one — Tyler Glasnow — has blamed the prohibition for a significant arm injury (Glasnow tore his ulnar collateral ligament and recently underwent Tommy John surgery).

If MLB wants to look across the Pacific for a solution, they’d probably start with a phone call to Koji Yasui.

Yasui is the general manager of the baseball division at SSK, the manufacturer for the Olympic balls. The company produces 3,500 boxes of 12 balls every month for a total of about 520,000 balls in a year.

The balls are used across different levels in Japan — youth, high school, college, industrial league — and for the renowned national baseball high school championship. Mizuno produces the balls for Nippon Professional Baseball, the country’s top league.

“But there is a history of pro teams using our balls to practice,” Yasui said.

Yasui said SSK only uses Japanese cow hides prepared by Japanese tanneries — and not just because of their expertise. Japanese tanners, according to Yasui, have encountered difficulty when trying to create similar balls in China and Taiwan, and they think the water is the reason. He claimed Chinese and Korean tanneries generate unstable results even with the same methods.

“It depends on the number, but it’s not like we have a huge surplus just sitting around,” Yasui said. “We’d need some advance notice. We’d also have to secure the materials. I think we’d need time to prepare to produce whatever would be asked of us.”

Yasui, who has worked at SSK for 40 years, said all the balls are the same size, the result of a meticulous assembly process with segments devoted to a specific aspect and multiple quality checkpoints. The balls come individually wrapped.

“It’s got this tack that they put on it before,” Ryan said. “So when you open that thing up, it’s ready to rock and roll.”

Japan’s record-setting heat and stifling humidity during the Olympics have created difficult conditions for pitchers — a few have used so much rosin that a puff of dust explodes with each pitch — but those asked said they didn’t have trouble gripping the baseball.

“It’s definitely a different baseball,” said U.S. pitcher Scott Kazmir, a 13-year major-league veteran who appeared in three games this season. “If you want to compare the two, I like the SSK ball a lot better.”

Mexico reliever Oliver Pérez, a 19-year major-league veteran, said the ball moved more than usual for him, perhaps because of the stickier grip. U.S. reliever Scott McGough, who is in his third season with the Yakult Swallows, said he didn’t see a difference in his pitch movement. He added that the rosin bag used in Japan is also better compared to the rock rosin used in the U.S.

“With a little sweat and some rosin the ball can get really sticky,” McGough said.

It’s not just pitchers raving about the balls. U.S. first baseman Triston Casas, one of the tournament’s standouts, said he liked the balls too because, effectively, they’re easier to hit.

“I think they’re a little whiter,” said Casas, who has three home runs in the Olympics. “I can see it better.”

Ryan said the balls fit in his hand more easily than those in the U.S. — both he and Kazmir said they seem smaller. He noted that several major league pitchers have asked him to bring SSK balls back to the U.S., and he offered to give the company his address for a shipment during a postgame news conference after tossing six innings in the Americans’ Olympic opener.

For now, Ryan, a 25-year-old right-hander acquired last week by the Minnesota Twins, can only campaign for a future change.

“It is — I can’t say this enough — the best baseball I’ve ever touched,” Ryan said. “Yeah, we need this.”

How it Relates to Science

STEM Sports® uses sport as a way to facilitate STEM concepts. When you break it down, there is science behind all sports. In this case, the game of baseball. From this article, you can see that the material played a role in how the ball played. This can be broken down into scientific reasons:

  • Sticky substance on the baseball for better control.
  • A whiter, glossier baseball is easier for players/hitters to see, resulting in players making better contact when hitting.
  • Rosin bag: rock rosin (U.S.) does not have the same stick and in turn effectiveness as the rosin bag used in Japan.

Another scientific reason for this can be weather. Hotter weather, particularly humidity, can cause the ball to slip from a pitcher’s hand especially if the outside of the ball has a slicker surface. If the ball has a stickier surface, as used in Japan, pitchers have the ability to control the ball. Which increases spin rate/rpm (revolutions per minute) and their overall performance.    

How it Relates to Technology

As the game of baseball continues to evolve, we can see the effect technology is having on player performance. Many players, especially pitchers, have voiced the need for ball technology to be updated to allow for a higher spin rate and, in turn, better performance. 

MLB pitchers have voiced this concern over ball-technology. They believe it needs to change to not only induce better performance, but also mitigate injuries as pitchers place more torque on the ball to increase spin rate/rpm. This results in pitchers placing more strain and tension on their arm, which can lead to injury and/or burnout. 

As technology continues to advance and we see it impacting sports more, it will be interesting to see if the voices of players are heard and there is a change made to baseballs. 

How it Relates to Engineering

In Japan, they are very meticulous in the engineering and production of their baseballs. Each one is individually wrapped after completion. This process allows for consistency and quality across their production process. This leads to uniformity in weight, density of the balls, and a constant on how much the ball’s threads are pronounced or protrude. All of these things lead to higher in-game performance for players.

In the United States, balls are mass produced. This can, by nature, lead to inconsistencies and will likely have a play-to-play and game-to-game impact on player performance. Assuming the U.S and MLB decided to take this feedback into consideration, they would use the engineering design process (EDP) to create new balls through testing and prototyping, incurring more rigid standards and production guidelines. Once they have optimized one ball, they would have these produced with new engineering standards. While there would be an investment in money and time, quality and amplified player performance would be the intended outcome. 

How it Relates to Math

Previously, we have talked about the spin rate on a baseball. This can be further analyzed using mathematics. Spin rate is measured by revolutions per minute (RPM). This has an effect on the trajectory of a pitch. The amount of spin that is put on a ball changes the plane that it will travel along. This is what creates curveballs, fastballs, sliders, etc.  


This article excited our company and was something we wanted to dive into deeper for our followers and users. The science behind sport is what our company is all about. What could be seen as a confusing or abstract concept, can be broken down in a way that makes sense to both the science lover and the sport lover. This is the exact type of teaching and thought process we have put into our STEM Baseball and STEM Softball curricula. We, as a company, believe that using sport can be a great way to break down science, technology, engineering and math concepts in a way that makes sense to all types of young learners. 

Do you wish to stay up-to-date with STEM Sports®?

Sign up below to receive the latest information on our STEM education, curriculum and available resources.