Football Players Have More Concussions Than Are Diagnosed, Study Suggests

The collisions that draw the most attention are usually the ones that happen in the open field: A receiver streaking across the middle gets blindsided by a safety, for instance. In the trenches, the hazards are less obvious but, perhaps, even more prevalent. Offensive linemen engage with an opponent on pretty much every play—when they don’t, it usually means they’re not doing their job.

“We’re backpedaling while someone is coming at us full speed,” Giants right tackle Justin Pugh says. “You use your technique, you try to use your hands as much as possible, but obviously the head gets put into that, and there is a lot of hand-slapping [against the helmet]. A lot of stuff goes on in the trenches you can’t get penalized for, and probably a lot of guys get hit or hurt.”

Part of changing the culture around brain injuries in football is gaining greater understanding of how they’re most likely to occur, and a new research study yielded interesting findings about the number of potential concussions that go unreported, particularly among offensive linemen.

The study, authored by Harvard Ph.D. student Christine Baugh, is based on a 2013 survey of more than 700 college players from 10 Division 1 FCS schools. Players were asked to respond with numeric answers to three questions based on both the previous football season (2012) and their entire playing careers: 1) How many times have you been diagnosed with a concussion by a medical professional? 2) How many times have you sustained an impact that you suspect was a concussion but was never diagnosed? 3) How many times did you get a ding or get your bell rung?

Players reported having about six times more suspected concussions than diagnosed concussions during the 2012 season, and about 21 times more “dings” or “bell ringers.” While offensive linemen didn’t have significantly more diagnosed concussions than the average for all players, they reported about 62% more suspected concussions and 52% more “dings” or “bell ringers” than their peers at other positions. (When providing numbers for their entire football careers, running backs reported significantly more “dings” or “bell ringers” than the average).

Those words—“ding” and “bell ringer”—are often used as code words for hits that may be potentially concussive. Players in this survey were more willing to admit absorbing these kinds of hits, though the words may have different meanings to different players. That highlights a central issue: No two head injuries are the same, yet much of proper treatment and recovery management relies on players self-reporting.

Not all of the suspected concussions reported in this survey would be diagnosed as concussions, nor would all the “dings” or “bell ringers,” but the results show top-level athletes are playing through impacts that may result in brain injuries. “Even in the era of concussion awareness, if we treat the diagnosed concussions properly, will that make a difference in the long-term?” says Chris Nowinski, co-founder of the Sports Legacy Institute and co-director of the BU CTE Center. “It also shows, in a sense, no matter how many changes the NFL game makes we’ve still got these potentially unfixable problems at the levels below.”

In recent years, the NFL has employed measures like the “eye in the sky” athletic trainers, who serve as injury spotters from a perch above the field, to catch more potential head injuries. The controversy at the University of Michigan, though, in which Wolverines quarterback Shane Morris was allowed to re-enter a game for one play despite showing signs of a concussion, emphasizes that the process can be better at all levels of the game.

For offensive linemen in particular, the study provides a different perspective on the subconcussive hits—lower impact, but with higher frequency—that players on the front lines absorb. Players were asked to report how often they experience concussion-related symptoms after a hit. Compared to most other position groups, offensive linemen reported more frequently experiencing symptoms that were not likely to be externally observable, such as dizziness, headaches and concentration difficulties. The responses also showed that offensive linemen, on average, returned to play while experiencing symptoms after a hit more frequently than their peers during the 2012 season.

The research paper suggests that many of the hits considered “subconcussive” may in fact be symptomatic impacts left unreported. Perhaps because they are more routine; offensive linemen may also be less likely as a position group to self-report, for any number of reasons, whether it’s less attention being paid to head injuries among their position-mates or a pride that they rarely come out of the game.

“Since there are normally just five guys that play the offensive line position, a lot of times you just don’t want to come out of the game at all,” Pugh says. “As a defensive lineman, you can come out for a few plays, and you rotate, so it is part of the norm. With us, I won’t say it’s frowned upon, but no guy wants to come out of the game and hurt the chemistry of the team or hurt a good drive.”

Pugh was sidelined during his rookie training camp with a concussion after he collided with a teammate while pulling out in space. He now checks himself after every collision, using that experience as his context for what the symptoms of a brain injury feel like. Not every player has that context, though, nor does every concussion feel the same.

Many rule changes have focused on those big open-field hits, but this study suggests a wider lens in making the game safer. Nowinski recalls a visit to the University of Miami last year to discuss head trauma with coach Al Golden, after which the coach had his team wear baseball caps during a non-contact practice to ensure that the linemen were not continuing to knock helmets.

For now, proper technique is one way linemen can lessen the frequency of collisions in the trenches.

“The best way to pass block is to see your opponent,” Giants left tackle Will Beatty says. “Keeping your head up; keeping your eyes on your target. It is physical, but you are not out there head-butting people each play. You want your helmet to be clean. You want to use power from your arms and your chest rather than trying to use your head in a block. Even though you are in the trenches, you can still protect yourself.”

This article originally appeared on SI.com