As of early September 2021, Shohei Ohtani of the Los Angeles Angels is leading the MLB in homeruns. Although he is Japanese, he boasts a body that is comparable to the top players in the MLB, and he continues to hit massive home runs that even astonish American fans. What make’s Ohtani’s muscles and body, which are the source of his power, so amazing?　In this article, we take a look at Shohei Ohtani through the lens of sport science.

Distance created by explosive bat speed and accurate bat control

I must admit that the thing I enjoyed the most about 2021 was watching Los Angeles Angels star Shohei Ohtani play. I think many other baseball and sports fans feel the same way, and I am filled with immense pride when I see the sheer level of interest that baseball fans in the United States have also shown in Ohtani.
Shohei Ohtani can hit, pitch, and run better than any player and the Major Leagues. What are the secrets behind the body that allows him to perform at such as high level? To answer this question, we talked to Professor Tadao Isaka, an expert in biomechanics and athletic training in the College of Sport and Health Science at Ritsumeikan University.

As his nickname Sho-Time indicates, the first thing that comes to mind when you mention Shohei Ohtani are his massive homeruns. Let’s take a scientific look at the dynamic arcs of his homeruns that make people shout “It’s gone!” as soon as they leave his bat.

Professor Isaka explains: “The distance that a ball flies is mainly determined by the initial speed of the ball and the angle of the swing. Other factors such as the rotation of the ball and air resistance are also involved, but their effects are small.
So, what is needed to increase the first major factor of initial velocity? The answer is extremely high bat speed. Naturally, the driving force behind a player’s power is muscle strength, so they must have extraordinary muscles.
Next, in order to create the best angle for a home run, you need to hit the ball in just the right position on the bat. The diameter of a baseball is about 7.2 centimeters, while the diameter of a bat is 6.7 centimeters, and both are made up of curved surfaces. The spot of impact on a bat to create the optimal angle is only about the thickness of a smartphone. So, you can imagine just how great Ohtani is when you consider how precisely he can control his bat against both blazing fastballs and breaking balls.”

A two-way player is like being an astronomical telescope while also having the precision of a molecular microscope

Shohei Ohtani is attracting a lot of attention not only for his powerful home runs, but also for his ability to pitch as he approaches his 10th win as a pitcher (as of September 17). He is a two-way player the likes of which have, until now, only been the stuff of anime heroes. What does a muscle expert think of his pitching speed, which sometimes exceeds 160 km/h, and his splitter, which has a huge vertical break, that are form foundation of his high winning percentage?

“In order to throw a ball that fast, you need a big source of power. In the same way that you can't drive a Cadillac with a mini-car engine, Ohtani has to have a pretty huge engine—that is, muscles. Not only that, he needs to be able to accurately judge where the bat will impact the ball when he’s at bat, and he’s pitching, he needs the command that lets him subtly control his power output.
To put it simply, it is like being an astronomical telescope while also having the precision of a molecular microscope. Ohtani has to have to have highly developed muscles that can function in an extremely broad range of scenarios,” explains Professor Isaka.

Of course, we cannot actually examine Ohtani's body, but just by looking at him, there is no doubt that he has very well-proportioned musculature. However, that alone does not explain how he is able to achieve his unprecedented two-way play at such a high level. Next, let's take a closer look at the muscles that hide beneath his uniform.

Is the secret to Ohtani’s total balance the fact that he throws right-handed while hitting left-handed?

"When you look at Ohtani, you can see at a glance that, overall, he has excellent proportions. He has the well-developed muscles that are necessary for any athlete, especially a baseball player, and he has an extremely symmetrical body.
My team has been studying the difference in muscle development between left-throwing and right-throwing baseball players (that is, players with different directions of rotation). According to our research, the more a player throws with the right hand while batting left-handed, the more balanced his muscles become,” says Professor Isaka.

Professor Isaka explains: "For example, in our study of university baseball players, we found that there were differences in the cross-sectional area of the psoas major, erector spinae, and multifidus muscles in players who pitch and batt with the same hand, while there were no differences in the size of these trunk muscles in cross-dominant players (e.g., players who pitch right-handed but throw left-handed). It is worth noting that right-left differences in the size of trunk muscles, including the psoas major, erector spinae, and multifidus, are a risk for lower back pain. Considering these results, it can be said that players who both throw and bat with their right hand are more susceptible to imbalances in their trunk muscles because they rotate their bodies in the same direction for both pitching and hitting, while players like Ohtani who throw right-handed and bat left-handed can easily maintain the balance of their trunk muscles because they rotate their bodies in opposite directions when pitching and hitting.
Some studies have shown that lower back pain impairs the intrinsic sense of location. Therefore, it is possible that lower back pain may cause a shift in a player’s sense of location in relation to the ball when batting. In Ohtani's case, the excellent right-left balance of his trunk muscles and a stable sense of location might be what has allowed him to maintain his phenomenal performance in both pitching and hitting.”

That being said, there are many players who throw right and bat left. So, what makes Ohtani so different?

"The rotational movement of the body is achieved when the rectus abdominis and oblique abdominal muscles in the abdomen and flanks work in lockstep with the back muscles (multifidus and erector spinae) mentioned earlier. In addition to this, Ohtani also has an extremely large amount of muscle strength that he can use to stabilize his lower body. When he swings the bat as a left-handed hitter, a lot of force is applied to his right thigh. On the other hand, when he throws right-handed as a pitcher, he has to firmly plant his left leg.
I believe that Ohtani’s right leg, which allow him to produce monster home runs, and his left leg, which he uses to generate his 160 km/h fastball, are well-balanced, allowing him to maintain both a high level of muscle strength and lateral balance in his lower body,” says Prof. Isaka.

Is there a meticulous training regimen that could expand the possibilities of future players?

In the MLB, which has over 20 games more than Nippon Professional Baseball, Ohtani has been playing as both a batter and a pitcher. That being said, he is one of the best players in terms of both home runs and wins, which is hard to believe, and many have already dubbed him a legend even though the season is not over yet. For someone like Ohtani, it can’t be easy to maintain his size and muscle mass.

"It is undeniable that Ohtani cannot maintain his strength level and muscle mass level just by playing the game. Surely, he does some degree of training on both off days and game days. I think it's impossible to explain how he can continue to perform at that level throughout the season without a very good balance between his upper and lower body, the right and left sides of his body, and careful muscle maintenance.
For us researchers, it's a really interesting body, so I'd like to see an MRI of his entire body, and I'd also like to see detailed measurements of his instantaneous power and muscle strength for each body part,” says Professor Isaka with a chuckle.

While researchers’ fascination with Ohtani’s musculature may know no end, many sports fans are also surely interested in how to avoid the risk of injury stemming from imbalanced muscles.

“Although we do not necessarily recommend that players pitch and bat with opposite hands (i.e., become cross-dominant), the data from our research clearly shows right-left differences in the trunk muscles of baseball players who pitch and bat with the same hand even at the junior high school age,
So, what might be important is to ensure that players who pitch and bat with the same hand maintain their trunk muscles on a daily basis to keep both sides of their body in balance. These young players and coaches should not focus solely on improving baseball performance and skills. I also hope they strive to understand the importance of training, conditioning, and maintenance to create a body that can reduce the risk of injury, “ explains Professor Isaka.

Physical training to avoid injury is the key to sports in the era of 100-year lifespans

Professor Isaka says the impact of Ohtani’s unprecedented two-way play is also huge. He remarks:

“I think the performance of star players like Ohtani will have a massive impact on the entire world of sports. The new frontier of high-level two-way play sets an example for other players that says ‘If you train properly, you can do it, too.’
What was previously impossible is now possible. It must be inspiring to athletes not only in baseball but also in other sports.
In addition, it can be inferred from Ohtani’s play that he is highly conscious of building a body that does not break down. He must be very particular about his training regimen, as well. I hope that he will remain an active part of the MLB for a long time. I hope that he will still hit home runs even after he is 40 years old, and that he will become the oldest active pitcher and home run batter.
I also hope that his performance will change the way senior citizens enjoy sports in the era of 100-year lifespans."

As the 2021 MLB season draws to a close, where will Ohtani stand? Will he win the homerun crown? We he be the MVP? With the weight of the world on his shoulders, we can expect a lot more greatness to come from Shohei Ohtani.