A strength assessment for the shoulder rooted in judo, devised by a soccer physio, tested in rugby and administered with a tool associated with the lower body has been adapted for baseball and used this past season by the World Series champion Houston Astros organization.
The Astros tested the use of ForceDecks — a leading supplier of force plates featuring an innovative software interface — in the minor leagues for the 2017 season after being shown a new shoulder evaluation that can be used for fatigue and injury monitoring.
A player lies face down in three positions, extending his arm overhead (making an upper-case I), then at an angle (making a Y) and off the side (making a T). In each position, he is instructed to press “as fast and hard as possible” on a force-detecting platform three times at intervals of 20 seconds. ForceDecks measures not only the maximum amount of force exerted but also the acceleration and deceleration from rest to the peak output.
The test creator — Ben Ashworth, a physiotherapist at Arsenal FC — said that with at least 20 measurements over time, a meaningful baseline is established whereby practitioners can detect both acute and chronic fatigue. For the Astros in the future, that could mean identifying not only how much of a toll the previous night’s start took on, say, Dallas Keuchel but also whether his recovery profile after 20 starts shows any sign of being worn down two-thirds of the way through the long season.
“We didn’t pick the test up and say, ‘Right, we’re going to pick a test that’s going to be baseball-specific,’” Ashworth told SportTechie. “We just know what we want is a test that could identify differences in force production and also in terms in terms of the rate of force development, which is the key to the test. That’s the bit that’s really the gold. Athletes can produce force slowly, but it’s nowhere near the meaningful actions of their sport and also nowhere near the kind of fast ability to protect their joint against injury.
“It’s pointless being strong without having that power and that speed element. That was a pretty easy link to make with any sport that uses the upper-limb dominance that transfers force from the trunk and the ground up through the arm.”
Astros sport scientist Jose Fernandez declined comment when contacted by SportTechie, citing club policy.
Force plates have long been the domain of lower body tests, especially for hamstrings and groins, looking for strength deficits and asymmetries that can be early markers for injury risk.
“It’s trying to catch an early warning if there’s been a maladaptation that would affect performance and, ultimately, could be a risk factor as well in terms of injury,” ForceDecks founder Daniel Cohen, a Ph.D. sport scientist on the faculty at the University of Santander in Colombia, said, adding with a laugh: “There’s some very exciting stuff coming out to provide the upper-body with a bit of love.”
Tracing the test’s provenance reveals a colorful bit of sporting crossover. Cohen and a fellow Ph.D. biomechanist, Phil Graham-Smith, were invited to Manchester United’s preseason camp in 2002 for a research project. After putting the David Beckham-led squad through tests, the academic colleagues needed six months to properly extract, compile and organize the results into a presentable data set — at which point Man U had no interest in antiquated information.
At that point, Cohen and Graham-Smith set about revamping the associated software for the immediacy required by a trainer or therapist in a club environment. A decade after their first visit to the Trafford Training Centre, they returned with the update, which received raves from the Man U staff. At that point, the pair turned their tool into a commercial product that is now being used by 15 of the 20 Premier League clubs, 14 NBA teams, seven NFL franchises as well as a whole slew of others ranging from West Virginia volleyball and Penn State football to the Royal Ballet School in London.
“Obviously we didn’t invent force plates,” Cohen said. “They’ve been around for decades. We just understood what the needs are of the practitioner in the training environment. We’ve also learned a lot through experience and through research as to guide people as what to look for, what variables to look at, what tests to do and so forth.”
One of the Premier League clubs using ForceDecks is Arsenal, where Ashworth has worked since 2012. He arrived to work at Emirates Stadium from the English Institute of Sport; there, he worked for three years with Great Britain’s judo team prior to the London Olympic Games. Ashworth has called that experience “the making of me” as a physio. His judo athletes were plagued with shoulder injuries, which he estimated as accounting for a quarter of all lost training time.
Much of the medical literature on internal and external shoulder rotation range stems from baseball, so Ashworth used that to guide his devising of return-to-play protocols for judo. While later collaborating on a research project for London’s Saracens Rugby Club with that team’s strength coach Patrick Hogben and physiotherapist Laura Tulloch and Arsenal’s sport scientist Nav Singh, Ashworth began ruminating on whether force plates, which provide great lower-body data, could be refashioned for the upper body.
Example use of ForceDecks for the upper body
With the Saracens, Ashworth instituted the shoulder test using ForceDecks — rather than the traditional model of using a hand-held dynamometer — to examine the rate of force development (RFD) in these “long-lever stress positions you would see in some of the throwing actions and a lot of the tackle actions that were required in rugby,” he said. Using the force plates to monitor load transfer across the shoulder girdle “makes intuitive sense,” Ashworth has said, even though this particular assessment is brand new. From that work, he recently wrote a research paper that he is about to submit which he said had “statistically excellent” results.
Around this time, the Astros’ Fernandez reached out while in search of a new shoulder test, Ashworth said, calling the baseball team’s sport science department a “very innovative team full of good practitioners.” Ashworth said that Fernandez tested 177 minor league players, which would help build a good sample size and check for validation of the results, although it was never used at the major league level. Word has since gotten out around baseball, and Ashworth has visited a few more clubs while recently in the U.S. during the Premier League’s dark week for international matches.
The fastest motion a human body can produce is an overhead throw, which of course produces undue force on the shoulder and elbow joints. The hope is for this new test to be a helpful new way in diagnosing pitchers at risk for injury — long been baseball’s epidemic — and also when they’re strong enough to take the mound again.
“It’s not a question of trying to wrap people up in cotton wool,” Ashworth said. “Sometimes it’s a case of using the test to enable you to go to the coach and say, ‘Yeah, go again. This guy’s ready. He’s robust and can tolerate this.’”
