MLB study identifies factors for rise in pitching injuries

Major League Baseball released a 62-page, yearlong study on pitching injuries Tuesday, identifying contributing factors to an increase in arm ailments -- including players chasing higher velocity and better "stuff" while exerting maximum effort more often, both in-game and non-game situations.

The study identified problems occurring at both the professional and amateur levels after interviewing over 200 people within the industry, including "former professional pitchers, orthopedic surgeons, athletic trainers, club officials, biomechanists, player agents, amateur baseball stakeholders, and other experts in pitcher development."

The study made broad recommendations -- including potential rule changes -- to address the increase in pitching injuries. MLB, however, said the study was just the first step in a process that needs even more examination.

For example, tracking pitchers' training and workloads from spring training until the end of the season was an easier task for the study than during the winter months, when players are essentially on their own. This seems particularly important because the study showed that pitching injuries -- both minor and more serious -- spike during the spring, at least suggesting that pitchers aren't properly prepared for the start of spring training.

The study cited  Shane Bieber and Spencer Strider being lost to Tommy John surgery in March as examples.

The league is concerned with pitchers potentially overworking themselves during the offseason in attempts to optimize "stuff" -- a term referencing the "composite movement characteristics of pitches, including horizontal and vertical break and spin rate," according to the study. Sweepers were cited as a relatively new pitch contributing to this issue. Weighted ball training was also identified as needing more study as there are mixed opinions on its contribution to injuries.

More than anything, though, the study concluded that chasing velocity is the No. 1 contributing factor to pitching injuries.

"I think there are a lot of factors," an orthopedic surgeon said in the study. "There's no question that if we take the simplest thing, which is fastball velocity, you can see how the average increase in fastball velocity has completely paralleled the increased incidence of injury. If you could take one factor, it's that."

The league also found that pitchers at the professional level are "at least somewhat aware" of the injury risks but choose the more dangerous style of pitching "because they perceive that the rewards outweigh the risks, particularly in the near-term."

This thinking may be filtering down to the amateur ranks as well.

"We understand throwing harder increases your injury risk," a pitching coach said. "That's true at a population level. Now for the overwhelming majority of human beings on Earth who aspire to play baseball at a serious level, that trade-off is worth it."

OTHER CONTRIBUTING FACTORS

In addition to the foundational issues of chasing velocity and "stuff," MLB's study uncovered tangential contributors to the rising injuries. They include, but are not limited to, the following:

Modern workload management strategies: Meant to protect pitchers, reduced workloads may actually be contributing to injuries. Pitchers tend to use max effort even more when they know they won't be in the game very long.

"I used to pitch to chase outs," a former MLB pitcher said in the study. "Now they chase velocity. I had to play a chess match to try to get 24 or 27 outs. Now it's a sprint to go as hard as you can, as long as you can. Starters have a reliever's mentality now."

The study especially found a "perceived" trend of minor league players being unprepared for a major league workload. Innings limits, more rest between appearances and restrictions on pitching on back-to-back days are likely impacting pitchers in a negative way once they reach the majors.

"When do you throw your first back-to-back?" a former pitcher wondered. "It's in the major leagues. Same with three out of four days. They're not getting exposed to it in the minor leagues. That's a lot of strain on your arm, if you're not accustomed to monitoring your warm-up pitches in the bullpen and used to the recovery afterwards to prepare yourself for the next day."

Training: Anecdotally, experts are concerned with a de-emphasis in cardiovascular and endurance training for pitchers in favor of the "power-and strength-focused training" that is more commonly prescribed in today's game compared to the past.

"There used to be starting pitchers doing endurance runs, and now we're in the power, short-burst, sprint-type training, and that's changed," one athletic trainer said. "It's okay to train for sudden bursts of power and what I'd call anaerobic training. I always tell people that's fine, but you need a basis of aerobic capacity to do that. ... We do too much of this heavy lifting, short-burst power. That's where I think we're missing it."

Prior history: Research within the study indicates that a pitcher's prior injury history can be a predictor for future injury. The study notes that as pitching injuries to continue to rise, and at younger ages, more and more players become susceptible to another injury as they climb the amateur and professional ranks.

"We're getting guys now out of the draft that have been throwing year-round -- our first-round guy had been throwing year-round for 3 years," one MLB athletic trainer said. "The wear and tear on him isn't going to be his first major league season, it's going to be from those previous three years."

Rule changes: The study was somewhat inconclusive as it relates to recent rule changes contributing to injuries, including the pitch clock that was instituted before the 2023 season. The evidence, according to the study, points to it not being a factor considering pitching injuries have been on the rise since the 1990s while the pace of the game has slowed down (before 2023). In fact, the slower pace may actually have contributed to more injuries as pitchers essentially took their time to throw max effort more often. That may not be happening as much with the pitch clock. Also, the trend of early season or spring training injured list placements points to the pitch clock having little to do with injuries, according to the study.

Covid: Experts within the study believe the shortened 2020 season due to Covid may have had a lasting impact on pitchers. "Unusual" training routines that season may have helped spike injury concerns over the past three seasons. The study suggests additional research is necessary to fully understand the impact.

Surgical advancements: Though medical advancements have allowed some players to return to the mound as good as ever, the study found that "incorrect perceptions" of surgery may provide a false sense of security for players. In other words, pitchers may be more willing to risk injury knowing they can always come back from it while still earning a major league paycheck and service time while on the injured list.

"They have such a faith in the Tommy John procedure, they're willing to sacrifice their own elbow knowing if they wind up tearing it, they can get it fixed," an orthopedic surgeon said. "By the way, with the new procedures going on, telling them they can get well in half the time with this internal brace phenomenon, it doesn't help at all with the relationship that pitchers have in their own mind about getting an injury.

"They don't realize that 20% of the ones who get it, don't make it back. They don't know that. They figure it's worth it, it's what I've got to do to be an elite pitcher, which is to throw 100 mph on every pitch or as hard as I can on every pitch, and take my chances, and if I get hurt, I'll get it fixed."

Amateur contributions: The study found chasing velocity and "stuff" at a younger age has been a contributing factor to the rising number of youth injuries as well. Not surprisingly, the study also found year-round training and early sport specialization as contributing factors.

"The velocity keeps going up, guys are getting bigger and stronger. As they keep getting stronger, their ligament doesn't necessarily get stronger," an orthopedic surgeon said. "I see a lot of kids. Some kids rip the bone off their elbow because their growth plate is weaker than the ligament. Instead of the ligament failing, the bone breaks off. That used to happen occasionally, but now it's happening more and more."

The transfer portal in college has been deemed a contributing factor, according to the study. Schools may have kids in their programs for short periods of time, leading to maximizing their performance during that window instead of developing them over several years.

CONCLUSIONS

Though further study on the issue is needed, according to the report, the league understands that creating a system where pitchers are "encouraged or required to moderate their activity and throw at sub-maximum effort to go deeper into games may be better for pitcher health."

Some experts suggest changes to the playing or roster rules to enact changes in training habits. For example, if there was an incentive to a player or team for the starting pitcher to last longer in a game, he may train differently -- perhaps with less max effort on every pitch.

Smaller pitching staffs would inherently require starters and relievers to pitch longer in games, again potentially changing pitching habits which may filter all the way down to the amateur levels. A limit to the number of transactions a club can make could be another way to force pitchers on the roster to adjust training habits.

The overall goal, according to the study, is a system that would "increase the value of pitcher health and durability, and decrease the value of short-duration, max-effort pitching."