The American Sports Medicine Institute (ASMI) has long been considered the authority on pitching mechanics studies as they have published the most peer-reviewed papers on this topic. Dr. James Andrews is widely regarded as one of the premier orthopaedic surgeons in the US, and has performed the most Tommy John (TJ) procedures in the world. Dr. Glenn Fleisig runs ASMI and has published numerous papers specific to the biomechanics of pitching. The combination of a world renowned biomechanics lab and a sports medicine practice that treats thousands of professional athletes annually naturally makes ASMI a premier sports medicine research facility.
ASMI has been studying the biomechanics of baseball pitching for over two decades. Dr. Fleisig is the Chair of Research at ASMI and is considered to be the preeminent expert on pitching biomechanics having studied it for over 25 years. The following introduction was published as the first part of a Q&A with Dr. Fleisig by Jonah Keri at Baseball Prospectus on January 23, 2014 and provides a good summary of Dr. Fleisig’s work at ASMI:
“Dr. Glenn Fleisig is the Smith and Nephew Chair of Research at the American Sports Medicine Institute, an organization founded by noted orthopedic surgeon Dr. James Andrews dedicated to improving the understanding, prevention, and treatment of sports-related injuries through research and education. Fleisig has worked closely with players and coaches at all levels, from youth leagues to the big leagues, teaching performance optimization and injury prevention methods.”
The following quotes from Dr. Fleisig were taken from The Why Files: The Science Behind the News website which recently wrote an article entitled Pitching the Biomechanics, and had some good quotes from Dr. Fleisig about the types of studies they perform at ASMI. The following excerpt is taken directly from that article:
The Institute has a library of more than 2,000 athletes from little league-aged kids to elite professional pitchers.
“We put two dozen reflective markers on them, and they throw from the pitcher’s mound in our laboratory while our cameras and computers record all the movements from windup to the follow-through after the release the ball,” Fleisig said.
The result is a complicated stick figure, which is compared by ASMI “biomechanists” with advanced degrees in ergonomics and biomechanical engineering against the range of other recorded pitchers.
“We’re watching the angle of their forearm to upper arm as they stride, where their front foot lands, the way their trunk swivels around to help generate speed as the arm moves through the throwing motion,” Fleisig said.
Timing and angles are crucial to a pair of the most important factors of a pitcher’s success: throwing hard and keeping the throwing arm in good working order.
“We know the biomechanics of proper pitching, the combination of good ball velocity without excessive stress on the elbow and shoulder,” Fleisig said. “We also know the difference in adults and children throwing fastballs and curveballs. The current challenge is to spread the science to the field.”
The following video provides a good summary of a typical pitching biomechanical evaluation at ASMI.
In Jonah Keri’s Baseball Prospectus interview Dr. Fleisig said, “So you get to pitchers, and we’ve been fortunate enough to analyze over 800 pitchers in our lab, from the smallest youth league pitchers to the big leagues, from healthy to previously injured. From this research, we’re able to form databases to see what healthy pitchers do. Once we’ve built databases, we have two goals. The first is adding to the body of knowledge on the topic, which means giving the course every year, talking to medical professionals who treat baseball injuries, publishing scientific articles, and getting information out to people who treat baseball players. Second, trying to help pitchers who come to ASMI themselves. Before we can ever do an evaluation on a pitcher, we’ll have done thorough studies, had our research peer reviewed, do further analysis, then apply our conclusions. That way by the time they get here, we’ll hopefully have a good idea of how to approach all kinds of different mechanical flaws and problems.”
In Keri’s Baseball Prospectus interview Dr. Fleisig said, “When a person pitches a baseball, he uses what we call a kinetic chain, which is a coordinated sequence of body motion, what in sports you’d call “coordination.” The top pitchers aren’t doing anything exceptionally well, there’s just no weak link in the chain. For example, we’re interested in looking at elbow and shoulder injuries. One thing we find is when a pitcher lands with his foot too far open–for a right-handed pitcher that would mean his foot was too close to the first-base side–he increases the stress on the front of the elbow and shoulder. Incorrect hip and leg action will lead to increased force higher in the chain. Younger pitchers often don’t properly use the strength in their hips and the lower part of the body. So they swing the leg open, land too early, and the energy from their legs and trunk gets passed to the trunk too early, before the arm’s ready for it. So when the arm is ready for it, that energy’s already dissipated. The arm ends up providing all the force, more than it’s able to handle.”
Dr. Fleisig adds, “Another flaw is when a pitcher drifts too early. A young pitcher may have a tendency to lift the knee towards the batter rather than lifting it straight up. That gets the legs moving before the arm is ready. You end up with similar strain to what you’d get with the first flaw. Another one: When a pitcher takes his arm out of the glove, the elbow should bend at 90 degrees. If you bend more or less, that’s a bad sign. What happens is once the arm is bent back, the palm’s facing the sky and the elbow’s bent 90 degrees, from that position the upper trunk can rapidly rotate to face the batter. If the bend is more than 90 degrees, the arm ends up closer to the head than it should be, and the pitcher needs to apply extra force to allow the elbow to catch up. If it’s less than 90 degrees, the injury risk isn’t as great, but you’ll most likely have lower ball velocity, which becomes a performance issue.”
In Keri’s 2nd Q&A interview, Dr. Fleisig adds, “We’re very interested in injury prevention on the younger side–Dr. Andrews and I are on the USA Baseball Medical and Safety Advisory Committee. USA Baseball is the governing body of amateur baseball in the U.S., which means picking and overseeing the Olympic team, but also governing youth leagues and high school ball. When we’ve found some answers, through USA Baseball we’ve been able to get those answers out there to young pitchers and their coaches. Around 1996, we started looking at the epidemiology of youth baseball (which includes Little League, Dixie League, Dizzy Dean League–different names in different parts of the country). USA Baseball asked ASMI to look at whether or not kids should throw curve balls, and how many innings they should throw. So we did our own research, and we also surveyed many top coaches and doctors about those questions. That led to some interesting findings: Although every youth organization was limiting the number of innings a kid could throw, the experts all felt we should be counting pitches, not innings, and paying particular attention to high-stress innings, where a young pitcher has to throw a lot of pitches to escape from a jam. The consensus on curveballs was have kids throw them once they’ve started to reach an age of maturity. So age 10 no, 13 to 17 is better. But these are largely opinions–educated opinions, but still opinions–at this point. Anyway, this all leads back to injury risk being a major factor more because the young pitchers’ bodies are still developing, not necessarily because of bad mechanics–we’ve actually seen plenty of youth league pitchers with good, repeatable deliveries, which is an encouraging sign of the quality of teaching out there. To be a successful baseball pitcher for the long run, you don’t want to have any overuse injuries obviously. But if you can’t underuse a pitcher and have him throw one pitch a year, or he won’t develop the technique and strength he needs to be successful. We’re looking for that fine line, what’s too much, and what’s too little.”
Lindsay Berra wrote an excellent ESPN article in March 2012 entitled Force of Habit: Science, not the scalpel, is the real solution for Tommy John injuries. Too bad few MLB teams are paying attention. In that article, Dr. Andrews said, “The No. 1 risk factor for UCL injuries is poor mechanics. The No. 2 factor is overuse. And if you overuse with poor mechanics, you’re doomed.”
Dr. Andrews wrote a book entitled, Any Given Monday: Sports Injuries and How to Prevent Them for Athletes, Parents, and Coaches – Based on My Life in Sports Medicine. In an interview with Dennis Manoloff of The Plain Dealer, Dr. Andrews describes his Sports Trauma and Overuse Prevention (STOP) prevention program. Dr. Andrews believes that specialization and professionalism are the two biggest contributors in youth injuries. Specialization leads to young athletes playing a single sport year round, which ultimately leads to overuse injuries. Dr. Andrews says that almost half of sports injuries in adolescents are the result of overuse. Professionalism refers to the concept of training young athletes like professional athletes in terms of their training regimen and year-round activity. In this same interview, Dr. Andrews states again, “The No. 1 problem in any specific sport is improper mechanics.”
However, in an interview on MLB Network Radio in April 2014, Dr. Andrews offers a different variable as the most important injury risk factor, “We’ve researched it in our lab as well as our foundations in Birmingham and Pensacola and the big risk factor is year-round baseball. These kids are not just throwing year-round, they’re competing year-round and they don’t have any time for recovery.”
Dr. Andrews sad in terms of Tommy John risk factors, “Year-round baseball is number one. Number two is playing in more than one league at the same time where rules don’t count [presumably innings limits or pitch counts]. In showcases for scouts, they try to overpitch and they get hurt. Poor mechanics continues to be a problem. Throwing breaking balls at an early age is a problem because it’s a high neuromuscular control throwing action that young kids can’t quite properly throw so the mechanics get them.”
Dr. Andrews also adds, “The radar gun is always a problem, too, because these kids are always trying to throw 90 miles per hour.” Matt Snyder from CBS Sports writes that Dr. Andrews beliefs that kids that throw harder than 85 miles per hour in high school are going beyond the “developmental properties” of the human body at that age and that going over that is a major risk factor.