By Joe Lemire
September 5, 2018
This four-part series examines the NFL’s $60 million investment in the Engineering Roadmap to develop research and technology to make football safer. Part one discusses the data behind the controversial helmet rule. This part outlines the engineering work supporting the roadmap. Part three discusses the crowdsourcing of innovative solutions. Part four looks at the future of the program and a new data collection device.
For most of wide receiver Nate Burleson’s 11-year NFL career, the onset of training camp resembled the first day of school. Players gathered in the equipment room and surveyed the available gear, clutching helmets and seeking peer affirmation.
“You going to put that one on?” Burleson, now a TV analyst, recalled. “What face mask are you wearing? Are you doing the visor? What about the cleats? How about the gloves? Are you doing the rib cage [pads] this year?”
Protective equipment was settled by what looked good, what others were wearing, or what they had worn in the past. By the end of Burleson’s career—he retired after a hamstring injury in 2014—he said players had become better educated on the safest helmets and pads, and sought them out. Selecting gear, he said, became like going to a favorite restaurant with a usual order.
More materials and more helmet makers have entered the market to offer greater choice, and at the same time testing standards have grown more rigorous. In 2018, the NFL and NFL Players Association banned the use of 10 helmets, the first time there has been a prohibition of helmets deemed unsuitable. The rankings of annual helmet tests are posted in every locker room.
When the league’s $60 million Engineering Roadmap was launched, there were two clear helmet objectives, according to Jeff Crandall, the chairman of the NFL’s Engineering Committee and director of the Center for Applied Biomechanics at the University of Virginia. The first was the short-term development of a better-performing all-purpose helmet; the second was a subsequent move toward position-specific helmets.
Players at each position were enduring a “different frequency, severity, or type of impact,” Crandall said. Cornerbacks and wide receivers suffered the greatest number of concussions. Quarterbacks suffered the fewest among non-kickers but, of that number, incurred 40 percent of their concussions when the rear of their helmets hit the ground.
“We should be able to stimulate ideas against how you’d better protect against that mechanism of injury for that player,” said NFL EVP for health and safety Jeff Miller. “Measuring it to what level of detail, understanding the complexities involved, isolating which parts of the helmet a particular position may be feeling the impact on what play types in what situations—it takes a fair amount of engineering work, and that’s what we’ve been engaged in over the last couple of years.”
The quarterback example makes intuitive sense, given how often players in that position are hit by an oncoming rusher while standing to make a throw, and then driven into the ground. But until recently that had never been quantified.
“We had to have an improved understanding of what’s happening on field—exactly how players are getting injured,” Crandall said.
The endeavor to find safe passage for football into the future is taking place on the aptly named Lewis and Clark Drive and a sister laboratory three football fields away in the leafy outskirts of Charlottesville, Va. Crandall and his deputy director, Richard Kent, lead the engineering initiative at the Center for Applied Biomechanics and its private consulting offshoot lab called Biocore. The project’s spokes extend outwards to 17 other contracted universities and companies.
“Certainly it is the expertise of those people, both the engineers that we asked to lead the work with Biocore as well as—and I can’t stress this enough—the quality of the people the Players Association has as their consultants,” Miller said. “It’s a terrific collaborative team that are leaders in the space of biomechanical engineering and, specifically, in injury prevention.”
The automotive safety industry is a major success story from which to pull inspiration and expertise. New technologies, new materials, and new standards have all lowered the risk of injuries and fatalities in auto accidents. While car crashes can still be devastating, the truth is that new automobiles are significantly safer than their predecessors.
“No one’s going to have an epiphany, and suddenly risk of injury to the body is going to go away,” said Dr. Barry Myers, an NFLPA consultant and biomedical engineering professor at Duke University. “If you look at places like, for example, cars—cars get safer and safer all the time. Our mileage goes up, our injury rates go down. And it’s an incremental process. Air bags were a big deal. Second-generation air bags were better. I think that’s what we’re going to see here.”
Crandall, Kent, and NFLPA consultants Myers and Kristy Arbogast all have great experience from the automotive realm and collaborated there long before football reconnected them. The prime culprit of head injuries in both disciplines is similar. Force is applied to the brain from an abrupt decceleration, whether from a motor vehicle crash or lineman collision, said Arbogast, the director of engineering for the Center for Injury Research and Prevention at The Children’s Hospital of Philadelphia (CHOP). That force can damage the brains neurons and the axons that connect them.
“The underlying biomechanics are the same,” Crandall said. “It’s the rotational motions that really cause deformations of the brain that tend to cause these axonal injuries, of which concussion perhaps would be on the lower end of the spectrum and some of the more catastrophic injuries that would occur in a car crash would be on the other extreme.”
The priority of helmet design in the past had been to prevent catastrophic head injuries, such as skull fractures. Helmets have accomplished that task pretty well, but they didn’t protect against concussions. Helmet testing standard-bearers NOCSAE and Virginia Tech, however, have or will implement rotational testing soon. Just because helmets historically haven’t been designed to prevent concussions doesn’t mean they can’t.
“The idea is, if you’re measuring the right metric and you have an improved understanding of what the motions are that lead to injury, then manufacturers can come up with designs that can reduce the angular motions, the rotational motions, and improve the performance of the helmet at mitigating impact forces that are applied to the head,” Crandall said.
Crandall’s lab has linked the science of automotive safety and military research with football, but sports differ from those by an order of magnitude. Those other areas see more catastrophic injuries, but minor trauma can still have a significant effect on elite athletes, and can be harder to spot.
“The injuries can be more subtle and more important to an athlete that just can’t tolerate a certain level of injury, so predicting those kind of injuries and understanding what causes them and what the thresholds are is actually very challenging,” Kent said.
The researchers engaged in the Engineering Roadmap have tirelessly pored through video, logging 150 data points for every diagnosed concussion. But video analysis is imperfect. The dozens of camera angles in NFL games are chosen by broadcasters to maximize fan appreciation. “It’s not set up to be a scientific experiment,” Crandall said.
Because there are no impact sensors currently permitted on the field, researchers needed better knowledge of the connection between what they saw on video and what was physically happening. In October 2016, they staged a huge production to recreate specific on-field collisions at Indianapolis’ Lucas Oil Stadium. They used impactors that could launch heavily-instrumented crash-test dummies. They used a laboratory-grade, motion-tracking system that’s considered the gold standard in automotive safety tests to identify the exact motion.
“Now we are modifying our testing standards to represent what we’ve actually seen on field from that video analysis,” Crandall said.
Anyone who has watched a football game can discern the obvious: large, fast athletes collide and fall injured. Something needed to be done. But no one had been able to record just how forceful those impacts were and just how the human body and brain responded. Now, with the knowledge gleaned from that 2016 experiment, the researchers can tease out impact direction, forces, and frequency.
“We didn’t have a lot of good data to drive priorities and direction,” Arbogast said. “Now we have some of that data and are continuing to collect it, which will give some of those other players—the material scientists, the helmet designers—data upon which to innovate. In the absence of that data, we may have been driving innovation in a wrong direction.
“Now we’re going to be able to do that based on a clear understanding of how concussions happen on the NFL fields. How does that vary by important parameters like position, like practice versus game, etc.?”
Another development has been more mundane, but telling. All of the researchers watched football differently before this project than they do now.
“Unfortunately, the first thing I do for every football game is try and identify what helmet every player is wearing,” Crandall said. “I can’t get over it.”
