‘Feedback loop to the coaching staff’ - How MLS clubs are pioneering sports science, cutting-edge technology and data to boost performance - and even predict injuries

Former Man United midfielder Roy Keane hates this stuff. There he was, on an episode of the Overlap podcast, sitting with Gary Neville, Wayne Rooney, and Jill Scott. Rooney, a former MLS coach, claimed that soccer players are running less these days. In a now-viral clip, Keane interjected and sneered, “The scientists are ruining football.” 

It’s an outdated view - and now one that is certainly incorrect. As soccer has evolved, so too have the demands on the body. Tactical innovations, an emphasis on pressing, and the athleticism of the game have forced organizations as a whole to ponder how they can best prepare their players to get fit, stay fit and execute at a high level. 

“If I'm going to create a training environment where I'm demanding my players press, and I want to play through a press, that's going to involve a lot of workload - more of a workload than might have happened 10-15, years ago,” Dave Tenney, director of high performance for Atlanta United, told GOAL. 

In truth, some have been preparing for years. In 2012, Tenney, then with the Seattle Sounders, had some time in the offseason. He went to Australia - but not necessarily on holiday. 

Australia had invested heavily in its sporting infrastructure prior to the 2000 Sydney Olympics. Part of their expenditure? Sports science. It wasn’t uncommon to see sports scientists and data analysts on the sidelines at Aussie Rules Football matches in the early 2010s. Tenney figured he had plenty to learn. 

“You had these high-performance models that were developing around that time, and they were just ahead of the curve,” he said. “And so as a result, I think a lot of those people that were trained went into AFL really early on, and they valued it greatly.” 

And he came back armed with compelling evidence: the Sounders needed to innovate. GPS, the tracking devices strapped onto undershirts now commonly worn by soccer players, had been around for a while. But not everyone in global soccer had embraced the value of the technology. Tenney argued that the Sounders simply had to. 

It wasn’t necessarily received well by the players. 

“Back in 2013, there were certain players that just didn't want to wear it,” he said. “They had never worn it. They don't want to wear it. The older players especially, didn't particularly want to be measured at that time.” 

But the results were clear. The Sounders, then a burgeoning franchise - albeit one with Clint Dempsey leading the way - finished fourth in the Western Conference. The next year, they won it. Of course, it wasn’t data alone that carried those Seattle teams. But they were fitter, stronger, and more durable than many of their opponents. They survived the hot summer months in ways few could.

And it took off from there. Tenney, now at Atlanta, is regarded by many as the founding father of sports science and technology in MLS, with numerous disciples who have implemented and improved on his methods. This is mandatory for successful franchises these days, teams looking to find even the smallest advantages by innovating. 

“If you utilize sports science and performance, especially if you're able to combine it with the technical, tactical aspect, and have good synergy between the two, I think it can be a competitive advantage,” Parr said. 

The most common way technology is deployed in soccer is related to injury prevention. Want to keep your players fit? Monitor them. 

It is no longer a question of running until you feel tired or leave a game because you cramp up. Teams now calculate these things precisely. Consider Charlotte FC. They built a state-of-the-art performance and training center when they entered the league as an expansion franchise in 2022. Parr essentially was asked to design it. 

And he wanted all the tech in his gym. 

“When we said, ‘We want this added, and this added, and this added, and this added’ we weren't really told no a lot, because they kind of looked at it as we're setting this up for the entire club moving forward,” Parr said. “We don't want to have to go and change it in a few years, and potentially spend more money.” 

It was all about return on investment. And so the Queen City is now home to a club that treats science like few others. One of their hallmarks? Treating injuries before they happen - well, sort of. 

It starts with what’s called “isometric testing” - basically a thorough analysis of muscle movements to “build” an idea of exactly how much energy is being used in a player’s running pattern. That’s fairly standard practice. But Charlotte goes a step further. They utilize technology to flag even the tiniest changes in a standard running form - indicating some sort of muscle issue forming, in real time. 

“We can take all that information and put it in a system and analyze their running mechanics,” Parr said. “Are there any issues that we're seeing, any big imbalances, big asymmetries, or issues with their running mechanics that need to be addressed?” 

And that can then be applied. If a player is returning from injury, for example, Charlotte can determine, using that preexisting data comps, if he is fully ready. Any discrepancies between the normal and current state suggest something may still be awry. In theory, it prevents recurring issues.

Of course, most teams hope to never get to that point. And that’s another element: deciding when, exactly, players are fully ready to return, and how much they should play in the interim. 

It is common to hear a manager claim that a player can manage an hour, or 30 minutes, or back him to play for a full 90. It may seem like press conference fodder, but, in most cases, it’s backed by science. 

“It's simply about working with your coach to get the right physical workload targets on each day, making sure you're not overdoing it, and then also using it as like a feedback loop to the coaching staff,” Tenney said. 

That requires extensive research. GPS is now more advanced than ever, with teams monitoring not only what a player’s status - distance run, number of sprints, relative intensity - but also how much exertion it required. Using that, they can calculate whether a player is “overloaded” (putting too much strain on his muscles) or “underloaded” (not enough to cope with high-intensity activity). 

Monitoring that, day after day, training session after training session, helps develop an accurate picture of how much an individual can give in a full-speed game. Of course, it differs player to player. Some younger athletes require extensive training to reach peak game readiness. Others, often veterans, just need to be kept fit and managed well. 

“If we're developing somebody for the future versus a 34-, 35-year-old captain who's been in the Prem, who we just want to keep ticking over, it's going to be very different,” Parr said.

Garrison Draper is FC Cincinnati’s VP of sport performance and health. His office is expertly placed in the FC Cincinnati training ground: right across from that of GM Chris Albright. Intermittently, when Draper is poring over data, or even taking meetings, Albright will interrupt. 

“The number of times I hear, ‘G, come here!’ and I have to walk across the hallway… I don't think it's by coincidence,” he says. “I think it's something that was very strategic, where they want this information available and they want these conversations to happen.” 

It’s emblematic of a club well aligned, where sports performance experts are trusted by those at the highest levels. Draper’s resume isn’t a bad one, either. Most recently, he worked with Inter Miami, helping keep the likes of Lionel Messi, Sergio Busquets and Jordi Alba performing (Alba demands perfection, Busquets is a bit more lax with his setup, he said). 

For Cincinnati, that connection is vital. It’s a matter of ritual at this point. At the start of every week, Draper gathers his staff to review at numbers, and then report back to head coach Pat Noonan. 

“My staff and I will hole up in a conference room,” he says, “and we're going to run through, ‘How did this guy perform on the weekend? How is he responding to that? What does our week look like?’ And then by the end of that meeting, I'm walking out and straight into Pat’s Noonan’s office and saying, ‘OK, we now have three days of training until our next match. How do we handle these guys?’” 

Most of the time, Noonan is receptive. 

It’s a similar system at Charlotte. Parr and the sports science team do not get to design training exercises themselves, but they do have a hefty say as to how their manager, Dean Smith, sets up drills to get the most out of his players - and also keep them fit. 

“We ask: What are the targets for today?” Parr says. “We want to have X amount of high speed, X amount of sprints, X amount of this, X amount of that. And then you have kind of drill builders that help you quantify based on all the times we've done these, the same drill in the past, these are the averages that we would get.” 

Not all coaches buy in. There used to be something of a generational clash in MLS, with coaches often ignoring underfunded sports science and medical departments. Roy Keane's outdated opinions still prevail at times. There remain some healthy conflicts here and there. But it's generally accepted that a strong collaboration between the scientists and the man in charge pays dividends. 

“Our coaching staff is so open to us and our understanding,” Parr said. “It's not our opinions or ideas. It's like, ‘No, we're giving you information based on what we're seeing’ and then they'll ask us questions.”

The FC Cincinnati dietician has no problem shaming her players - in a constructive way. They will not skip out on the carbs, or they will certainly be called out.

“She's sitting there watching, and she can say, ‘Oh, you skipped the carbs here. Remember, we've got a big game coming up. Carbohydrates are important,’” Draper says. “And the guys are literally there, like, spooning carbs onto their plate.” 

That’s the basic stuff. These days, players know that they have to be on top of their nutrition. Clubs plan that meticulously. And they can tell when their players cheat, too, thanks to 24-hour tracking data. 

But the more complex things sometimes still need explaining. Back in 2013, some players didn’t want to use GPS systems. 

Now, things are different. Cincinnati test blood samples to monitor glucose and iron levels and measure lactate thresholds to check fitness - which has become, in some cases, a far more scientific version of the dreaded bleep test. Players used to hesitate. Some just didn't like it, Draper admitted. Now, they go along with it.

“If a player doesn't want to do this, we can't force them. But when they see how it's helping them, even if it does hurt that they get their finger pricked... it's pretty hard to say no, because they know they're receiving care,” Draper said. 

Charlotte encourage their squad by gamifying things. It’s risky to ask players to get into official competitions in individualized training programs, but the goal of breaking one’s vertical leap mark, or getting the right number of reps in at a specific weight, certainly scratches a competitive itch. 

It’s also beneficial, Parr says, that the data is set up nicely. 

“It helps that it's on an iPad, and it kind of looks like a video game. So the players buy into that stuff more because they get the instant feedback. It also drives a little competition,” he said. 

And, of course, some players are just nerds. They crave the info. 

“I love looking at data. I love talking to our data analytics team in the organization about these things,” Matt Freese, the Harvard-educated USMNT and NYCFC goalkeeper, told Sports Business Journal. “I just think it's really interesting. It can shape a strategy of a team to a degree. It can't completely take over what the philosophy of the team is, but it can point you in the right direction.”

Tenney flirted with the Orlando Magic for a while. He worked for the NBA franchise from 2017-2020, and tried to implement some of his soccer methods. But he was soon called back to soccer, driven by new opportunities. MLS continued to innovate, and he wanted to be a part of it. 

That’s not an uncommon story. While MLS has shipped off talent overseas to the likes of Liverpool and Juventus, others have flocked in. Where it goes next is hard to determine. Science, at its very core, is hypothesis, trial and error. 

Some clubs are in danger, Parr argued, of using too much technology. And sometimes it just won’t work. You might need to accept that you will invest in some technology that, ultimately, doesn’t add much value. 

“Sometimes we have to go with our gut, and we might need to invest some dollars to watch it fail and watch it burn,” Draper admitted. 

But then there are the bits that can be tweaked and might yet work. Draper was an invited speaker at a conference held by the U.S. Department of Defense a few years ago. There, they showed off a technology called Lidar - a laser system used by national security agencies, and also, on occasion, in autonomous cars. 

He believes a version of that, in the near future, could be applied to gather real-time athlete data. There is also a world in which GPS systems won’t be needed, such is the detail of on-field cameras. Some, such as Draper, have called for a league-wide database that provides exact details on injuries when a player gets transferred, providing precise information right down to individual bumps and bruises. 

“Do you have the medical information that he had a hamstring strain earlier this year? Could you give us the MRI results? Talk to us about his rehab? Instead, it's in a file where the player can just say, ‘Here's everything I have, it should be updated,’” Draper suggested. 

And then, there’s the cool stuff. Atlanta are building out their training ground, expanding it to 50,000 square feet. As part of the expansion, they will install a chamber that simulates training at high altitudes to refine conditioning. 

Charlotte are using heart rate and muscle data to determine exactly how effective their players’ off-ball runs are. Cincinnati are using third-party technology, Orreco, which analyzes blood samples to track stress responses in real time.

And at the center of it all is sound theory, a focus on the athletes, and maybe, just maybe, predicting injuries before they ever happen.