NFL leaning on data to limit foot, leg injuries

The precise measurement of NFL players is nothing new to anyone who has watched the league’s combine. But such specificity extends far beyond Indianapolis to every locker room in the league, where 3D scanners are used to measure a player’s feet to the millimeter.

Despite such technological certainty, Seattle Seahawks equipment manager Erik Kennedy often finds himself having to convince players that their shoe size is what the scanner says it is. Like most people, NFL players often grow up believing their feet are the same size, don’t grow in adulthood, and that even good shoes need to be broken in. In fact, none of that’s true.

Kennedy and Nike, a Seahawks sponsor, have worked together for years trying to make shoes fit better for NFL players, and now their efforts are just part of a leaguewide attack on lower-body injuries.

Three years after deploying $100 million and the full force of its medical expertise toward mitigating head injuries, the NFL is using a similar approach toward the lower extremities. Leg injuries such as torn ACLs, pulled hamstrings and turf toe may not represent the existential threat to football that concussions do, but together they comprise more than 60% of all injuries and eight of the top 11 reasons players miss games.

Among the key players missing time this year to lower-body injuries are Bengals wide receiver A.J. Green (ankle), Carolina Panthers quarterback Cam Newton (foot) and Minnesota Vikings wide receiver Adam Thielen (hamstring).

“The league’s work on helmets has started to show massive gains, and you need to, that’s the most important thing in the game,” said Kennedy. “But No. 2, and what’s going to keep you out of the game, is your footwear.”

Seattle and seven other clubs now have RFID tags in every shoe their players wear in games and while training, generating data on style, model, size, usage and injuries that occur. The league hopes the data will be enough for analysts to find common threads that can be fixed.

Keeping athletes healthy is a worthy goal by itself, officials say. But the proliferation of lower-body injuries is a business problem with a modern business solution: data gathering and advanced computing.

“Lower extremity injuries account for substantial time lost for players, and it obviously deprives the game of star athletes more than we would like,” said Jeff Miller, executive vice president of health and player safety innovation for the NFL. “It is our contention that using some pretty logical, straightforward and time-proven injury mitigation strategies, we should be able to drive that number down over time.”

There are three simultaneous lines of attack underway:

Feet/Ankles: The league and its partners gather as much data as possible about field conditions, including types of artificial turf and different varieties of grass, as well as the durability of different shoes and what shoes are being worn when injuries occur. Meanwhile, research is accelerating into what exactly happens inside of the body when a ligament is stretched beyond its natural limit, or what specifically causes turf toe.

This year, the NFL started rating cleats in the same way it rates helmets, in an attempt to steer players toward the higher-performing ones. On Nov. 25, the league announced an open competition for analysts to study currently available data on artificial turf and natural grass to find new insights on how the surface affects the body’s movement.

Soft Tissue Injuries: A joint NFL-NFLPA committee being led by Leigh Weiss, New York Giants physical therapist and director of rehabilitation, has begun looking at when these injuries — such as groin strains and hamstring strains — peak, paying particularly close attention to the preseason.

The causes and potential solutions of these non-contact injuries are especially difficult to discover because there are so many different potential factors. Sleep, hydration, stretching and the natural variations from body to body all might play a role.

All of those variables are being fed into a massive epidemiological database managed by IQVIA, a Connecticut-based health data company. They hope that by crunching the numbers they can determine the optimal amount of sleep, nutrition and stretching that will minimize pulled groins and hamstrings. “We don’t necessarily need to talk large-scale changes, but instead taking small-scale steps over time that will build to a reduction in these kinds of injuries,” Weiss said.

ACL Injuries: The NFL’s Musculoskeletal Committee is looking back at every ACL injury in the league over the past two years on video review, from as many angles as possible. The hope, Miller said, is to “To try to understand the mechanism of injuries and see if there are things we can pick up on.”

Collectively, the lower-extremities injury mitigation push is a long-term project. But league Chief Medical Officer Dr. Allen Sills has asked the group to develop some kind of injury reduction strategy by the 2020 combine for hamstring, soft tissue strains, ACL, knee ligaments and mid-foot fractures.

“This is a multiyear effort, but at the same time we feel like there’s such a high burden of injuries that we don’t want to wait several years to come back with interventions, because these are real-world injuries affecting our teams and players every week,” Sills said. “We want to bring the same level of intensity and focus that we did with concussions.”

Insiders have high expectations, Miller said. While sports medicine has long been trying to cut down on injuries, the technology to gather data and the computing power to analyze it at scale is relatively new, leading them to believe big gains can still be made.

Like with the players and their ill-fitting shoes, a side benefit of the data-backed approach is to convince the football world that nothing should be simply accepted at face value. 

“It’s not OK to simply say this is the cost of doing business as a football player,” Weiss said. “We really believe the game can continue to be made safer by better understanding the injuries and specific targeted interventions driven by this data.”

Editor’s note: This story is updated from the print edition.