Why NFL Helmets Will Never Be Concussion-Proof

Experts agree, even if a concussion-proof helmet were possible, such a solution would bring new injuries of its own—to the sport and its players.

Imagine that you drive a car straight into a building at 40 mph. Despite airbags and seatbelts, you’d probably feel lucky to be alive. But when an NFL wide receiver meets a safety head-on, we expect them both to get back up to play second down.

What’s the difference?

"In a car crash, you stop in a matter of feet. In an NFL impact, you stop in inches," one expert tells me.

In the eyes of physics, a big hit on the field can be just as devastating as a car crash—or in many cases, worse. We’re expecting a mere 1.5 inches of foam and candy shell to decelerate a player’s head gently enough to prevent their brain from bouncing around inside their skull and causing poorly understood, but permanent and devastating injury. After talking to some of the brightest minds in helmet design, helmet testing and football physics, the elephant in the room became clear: A concussion-proof helmet is a pipe dream. If the NFL wants concussion-free football, they’ll need to redesign football.

That said, conditions have never been riper for disruptive technologies to increase player safety. And for the first time in football’s 200+ year history, we’re finally developing the methodology to separate our best helmets from the decorative chunks of plastic.

Testing Evolution

Just two years ago, a team led by Dr. Stefan Duma from Virginia Tech released the first ever five-star crash rating for football helmets (PDF). It’s one reason that Duma likens the NFL of today to the auto industry in the 1970s. Originally, all cars were rated by a basic pass/fail crash test, and it wasn’t until Congress passed legislature for a five-star crash rating system that car companies had the impetus to do better.

Before Duma’s testing, the same was true for helmets. The industry’s only concern was whether football players could take a hit without fracturing their skull or sustaining subdural hematoma. Concussions—or any other traumas—weren’t part of testing. So designing helmets became a limbo bar. If a manufacturer came in anywhere below crushed skull territory, their helmet was thrown in the approved pile.

"Our rating system is the first that actually shows people that some helmets are better," Duma says. "One of the things we wanted to do was provide a mechanism for improved design. You’ll never have a concussion-proof helmet because injury is all about risk. But the better helmets lower your risk. That can be substantial. We found the best helmet lowered risk of concussion by 85%."

The World’s Best Helmet

Duma’s top-rated helmet today is the Riddell 360. Priced at about $400, it features a hard polycarbonate shell to bounce off an impact and an energy absorbing foam lining to absorb the aftershock. The pièce de résistance is its huge, spring-like facemask optimized for forward-facing collisions. The entire ensemble is so effective that it can cut the peak force of a head-on-head impact in half when compared to the league’s worst helmets. (And it just so happens, Riddell’s VSR-4, discontinued in 2010 but still supported for factory refurbishing, is one of football’s worst rated helmets.)

But why should players wear helmets at all, one might ask. In the mid 20th century, as many as 30 players were dying a year due to head injuries. Helmets were the byproduct of the NFL’s first head-trauma scandal. The first were thin, hard leather. Then they adopted plastics, padding, and face masks. As we learned more, the focus quickly became, not just hard protection, but the shock absorption of softer materials. This approach worked. Since the 1980s, we haven’t had a single skull fracture in the NFL. Today’s Riddell helmet is bigger than its predecessors, but it’s ostensibly the same design we’ve been building on for decades.

Each product Riddell releases follows about two years of R&D. They create a prototype. They fill it with a human head surrogate (complete with a brain-like liquid center) used in pass/fail certification testing. They smash it to simulate a head hitting the ground. Then they use another human head surrogate called the Hybrid III (found commonly in the auto industry’s crash test dummies), then they pummel the helmet again, focusing on specific angles of impact more like one might expect in an NFL game. Following that, Riddell seeds their new line to teams to test out in real-world conditions.

But with all this research and testing, can Riddell promise a concussion-free helmet?

"I wish we could," says Thad Ide, SVP of Research and Product Design at Riddell. "With current technology and understanding, we’re just not there."

The problem is ultimately one of physics. All helmets work under the same principle. The force striking one’s head—acceleration mixed with mass—can’t actually be prevented. Physics says that energy has to go somewhere, right? What good helmets do is lengthen the duration of the impact itself (in the hundredths of a second range), reverberating energy through various structures and materials, to smooth a hit from a sharp, high-g strike to a relatively smooth curve of deceleration. Consider landing on a concrete floor or a pile of pillows. Which impact takes longer and which impact hurts more?

"I think that it’s true that football helmets are 85% as good as they’re ever going to get," Dr. Timothy Gay, University of Nebraska physics professor, writer, and industry helmet consultant tells me. "The optimal football helmet won’t be much better than the helmet you can buy right now because there are just physics restraints on the kind of padding you can use. We have a pretty good micro, nanotechnological understanding of how materials work. And basically, there are limits on what padding materials can do for a given thickness."

That’s an interesting point—what if we just increase the padding’s thickness?

Maybe We Need A New Paradigm

"You can certainly make a helmet that’s concussion-proof," Gay tells me later, countering his own argument that had just sounded so convincing. "All you have to do is put 15 inches of foam rubber on the outside of the helmet." This idea may seem as ludicrous as wrapping a fully padded football player in one of those novelty sumo suits. But it just so happens, there’s a company doing pretty much just that.

ProCap is a soft wrapper for football helmets that’s actually been around since the late 1980s. Most famously adopted by San Francisco 49ers offensive tackle Steve Wallace, this extra layer of padding is a means to further slow the impact of the blow. Its known downfall? The soft outer padding can look a bit silly. There are also claims—though no studies that I could find—that the friction generated by a soft outer shell could lead to a neck injury.

ProCap’s inventor wasn’t available for comment, but when I asked Duma about the potential of foam-wrapped helmets, he said that his lab hasn’t tested any, as the ProCap has generally existed as an add-on, not a self-contained helmet in its own right. But he did have the first reasoned red flag to this cult-worshipped design. In the 1990s, Duke researched the possibility of adding padding to the ceiling of cars to protect passengers in the case of a rollover. What they found was precisely on-point with football’s current fear, that the softness actually distributes pressure to the neck, which can cause horrendous spinal injuries. "The notion was out there, ‘Let’s put 4 inches of foam in the ceiling!’" Duma says, "but you may just end up with a bunch of quadriplegic people." It makes sense. Just look at your car. You have side doors full of foam or even airbags, but the ceiling is covered by a glorified sheet.

So … Another New Paradigm

Another, equally enticing possibility is to model football helmets, not after football helmets, but after motorcycle helmets. Most football helmets are designed to be reworn until they’re refurbished. They have to serve play after play. But motorcycle helmets are designed differently. They use a more drastic energy-absorbing foam and a hard shell that isn’t afraid to crack. The downfall is that these helmets completely disintegrate upon impact—they’re totally ruined—with the interest of absorbing every bit of energy possible.

But David Rogers, VP of Concept Development at Gentex, the leading manufacturer of helmets for the Air Force (that owns companies that have designed everything from football helmets to special ops helmets), argues that single-use helmets are not the panacea they appear to be. Beyond the fact that players would need to pause each play to swap out helmets, even our best motorcycle helmets are only designed for 18 mph impacts (not our theoretical 40 mph maximum hit of two players running 20 mph). And as Rogers puts it, should you have a head-on collision in a motorcycle helmet at 18 mph, "you probably still have a concussion, but you’re not dead."

"Not dead" isn’t really any sort of improvement.

The NFL Can Do What Helmets Can’t

After going back and forth with experts with every conceivable conspiracy theory I could imagine, the consensus was obvious: A concussion-proof helmet is either impossible, or its requirements would affect play so drastically that it would either impair the sport or lead to other injuries. Even if we can mitigate the impact of the average tackle (and current helmets actually do this exceedingly well), the worst hits in the NFL are exponentially harder than the baseline. I’ve heard estimates that 5 to 10 hits in any given professional game are of concussion caliber. It’s no wonder so many of our players have been out this year with brain injuries.

"The helmet is the third barrier of defense," Dr. Duma tells me, when I ask what can change. "You have to work on the rules, and you have to work on the coaching."

Football is a brutal sport, and it always has been. The hits seem big only because they are. Sooner or later, driving a car into a wall at 40 mph is going to hurt you, with or without a $400 piece of plastic on your head. Every single helmet expert agreed that we can redesign football much more quickly and effectively than we can redesign the football helmet—in fact, most suggested the idea to me. The only question that remains is, are we actually willing to change football? Or do we value the spirit of the game more than the lives of the people playing it?

[Image: Shell and xray via Shutterstock]

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  • Arthur Holt

    Could you look at using shock absorbers used in industrial design for example hydraulics or pneumatics and apply them on a small scale in a helmet, if you separated helmet into 2 layers with a gap in between containing these shock absorbers would this help or cause further problems. Would be great to hear some thoughts on this

  • frankelee

    What a load of horse**** all their testing is. The NFL claims to be so worried about concussions but they only really do testing to see who among the big helmet makers has the best design by a few percentage points. The hard exterior helmets cause injuries, they don't prevent them, and the only excuse they have is that somebody somewhere once suggested they could cause neck injuries. The rock hard helmets they use today jam the man wearing them all the time, they don't guarantee to glance off the energy of a hit, and with modern materials they could easily make helmets that are both slick and which can crumple inward to the padding on impact.

  • Seattle Tech

    I haven't seen much discussion on simple devices that measure severity of impact throughout the game. When I move fragile items across the country, I can easily attach in inexpensive sensor to the box and then evaluate what impact if any the box had before I open it at its destination. I believe there are devices like this in action on various football fields where trainers can monitor whether players have been impacted and pull them off the field if the sensor indicates a concussion-causing impact. Players can experience concussions even if they are not symptomatic - allowing a player to decide whether they're injured or not is not the answer.

    As the article clearly points out, no helmet can be concussion proof and changing the game is not a viable option. What can be done, however, is quickly evaluating whether an impact occurred and pulling players off the field to prevent the second impact. From my understanding working through my son's concussion last year, it's the subsequent impacts that can be life-changing experiences. I realize it's far easier to pull a youth player off the field than a multi-million dollar NFL player due to the competing priorities. Football needs to get ahead of the potential legislation and find ways to reduce the risk of the sport. The last thing we need is well-intentioned legislators intervening to "help".

  • Joshua Peachy

    I didn't see any mention of rotation or torsion of the brain, caused by hits which aren't straight on the head or body. The article I linked below mentions an insert which allows the helmet to slip around the head slightly, in order to reduce the twisting forces exerted on the skull, then brain.

    Mentioning motorcycle helmets is interesting, because there is one which uses a skin on its surface which slips on impact, in order to reduce twisting forces. Take both anti-twisting methods, plus variable viscosity padding, which is harder on high impact, soft on low impact, as well as remote telemetry gyroscopic and thermal sensors, and we might have a winner.

  • Aaron Smith

    The helmet needs "shoulder pads".  Yes, it may look ugly, but a HUGE soft  protrusion from the front of the helmet could work wonders.  Or even "antlers" to turn the helmet away from direct contact.

    The core premise of the helmet is a hard exterior and soft interior.  This is all wrong.  You need that PLUS another soft exterior layer.  The hardness of the helmets and their smooth spherical shape guarantees a violent localized event.

    Fact of the matter is helmets are weapons and this has to be considered along with protection when redesigning them.

  • disqus_f1NobGV0kt

    The fact is that its not simply about reducing impact. Thats really good for protecting against skull fractures, but concussions occur due to the acceleration of the head. Creating bigger helmets with increase the ability of the head to swivel on the neck and increase concussions.

  • Marc F Pelletier

    Mark, nice piece. It is true that helmets will not prevent concussion. On the other side of the coin, I have spent the last 5 years developing a neuroprotectant for stroke and traumatic brain injury.We can block water movement into the brain - blocking the brain swelling that follows trauma. We can triple survival in animals by reducing the increase intracranial pressure. We are now transitioning to the clinic. I can be reached at marc dot f dot pelletier at gmail dot com if you would like to know more about it. 

  • BertPC3

    No helmet can be concussion proof.  The real discussion should be about creative helmet design that can significantly reduce the concussion rate.  The value of your article is the call for a new paradigm and you found it with the ProCap.  Take the Riddell 360, or any helmet for that matter, and add a ProCap and there will be a significant drop in probability of concussion.

    The reason for this that the forgiving impact surface extends the time of the event.  As your article states, "this is the design objective".  It's unfortunate that Dr. Duma dismisses this potential on the notion that 4" of foam on a car ceiling will cause neck strain.  A much more relevant car metaphor would be modern soft bumpers compared to the outdated hard ones. 

    You correctly point out that rumors without supporting science have contributed to blocking the outer padded technology from solving the concussion problem.  There is much science gathered independently by Wayne State, Penn State and George Washington U. that the ProCap reduces both concussions and neck strains.  On the field in the GWU Survey found there were 3 times the neck strains in the non ProCap population and zero concussions with ProCaps vs. 6 without ProCap.

    The one valid critique concerning ProCap looks has finally been addressed with the new lightweight PC3, [visit]  Also, the ProCap is more slippery than any helmet or accessory out there.

    Finally, those helmet "experts" who claim "it is easier to design football than the football helmet" are ducking responsibility.  Rules changes have been tried to the point that officials and players alike are confused and the alarming concussion rate continues.  Now the President is talking about it and pros are reluctant to let their sons play.  Hard shell helmets do not address concussions.  Soft shell helmets do.  Lets take a close scientific look at ProCap technology and do something meaningful to reduce concussions.     

  • NFL

    In answer to your question, we value the spirit of the game more than the lives of the people playing it.

  • Jefdhamilton

    Another key point that must be addressed is the Mouthguard that is being utilized and its effectiveness to absorb the direct and indirect forces on the orofacial structure and Temporal Mandibular Joint. Studies have now proven that proper protection of the TM Joint is critical in the reduction of concussions. Mouthguards that are specifically designed to meet the needs and parameters of each athlete, like the ones from BiteProMouthgear, are essential to provide the greatest levels of protection and performance.

  • Buckspa

    Didn't a mouthguard company just get fined by the FCC for making claims about reducing concussions that were false?

  • Jef Hamilton

    I have not heard of this myself though I also would not be surprised by some of the claims that have been made... do you know who that company was??

    BitePro Mouthgear says that they can significantly increase orofacial protection and help reduce the impact forces of a hit. Their mouthguards are designed to provide extra "padding" for the TM Joint which is associated with one important type of concussion. They do not claim that their devices will eliminate the chance of a concussion.

  • Melinda Stanley

    Never say never! Addressing helmet safety is critical to ALL players and fans who love the sport--much emphasis on NFL--please consider the peewee/youth leagues and Middle/High School athlete (football, soccer, cheer) who are potentially experiencing  significantly more profound and lasting injuries as their brains are still developing.  The progress of Swedish researchers cited by Tom Foster in this Popular Science article is compelling and promising.  Compelling reasons to work globally--it's Nobel Prize worthy :-)


  • Kostal

    Hummm...I posted this an hour or so ago and it looks like it
    was deleted???by whom?

    Your science is incorrect. 
    Two objects that meet each other at 20mhp do not equal a force of an
    object hitting a stationary object at 40mph. 
    It is NOT additive.  The force to
    each of the objects is the force equal to one object hitting a stationary
    object at 20mph.  Very close to the 18mph
    you list in your article as

    Hummm...I posted this an hour or so ago and it looks like it
    was deleted.

    Your science is incorrect. 
    Two objects that meet each other at 20mhp do not equal a force of an
    object hitting a stationary object at 40mph. 
    It is NOT additive.  The force to
    each of the objects is the force equal to one object hitting a stationary
    object at 20mph.  Very close to the 18mph
    you list in your article as sustainable with a good motorcycle helmet.  The assumption that concussion proof at 40mph
    is unattainable maybe 20mph, it's a different story entirely.  See MythBusters...they tested this exact

    Hummm...I posted this an hour or so ago and it looks like it
    was deleted.

    Your science is incorrect. 
    Two objects that meet each other at 20mhp do not equal a force of an
    object hitting a stationary object at 40mph. 
    It is NOT additive.  The force to
    each of the objects is the force equal to one object hitting a stationary
    object at 20mph.  Very close to the 18mph
    you list in your article as sustainable with a good motorcycle helmet.  The assumption that concussion proof at 40mph
    is unattainable maybe 20mph, it's a different story entirely.  See MythBusters...they tested this exact

  • Mark Wilson

    No one deleted your comment. I actually responded to it. Try to relax. Ease off the Mythbusters! 

  • Mark

    The idea that football players should remove their helmets like in rugby is an idiotic argument that needs to die. Like the article says, football players started wearing helmets because people were DYING while playing. What part of this don't you people understand? Rugby and football aren't even remotely comparable. Actually, no sport compares to football. Football has the world's biggest and fastest athletes running full speed into one another. Nothing in any other sport comes close. If an NFL team were to play rugby against the world's best team, there would be serious injuries and a moderate probability of death and paralysis for the rugby team.

  • Thatmanstu

    Football without pads is a game played on sandlots across the country and has been for many years and by virtually every professional player as well as tens of millions who never play organised football. Leading with the head just doesn't happen(more than once) because of the lack of armor. Rugby players are forbidden by rule,trained by habit and governed by self preservation to not lead with the head. Otherwise the impacts and the game are much more similar than your statement would lead one to believe. Any differences in the game structure are leveled out by the need to preserve one's face.A Safety taking a ten yard run on a vulnerable receiver is unique to football,but the potential for a launching missile hit is greatly reduced and the need to execute a clean and effective tackle is increased sans helmet. NFL defenders have become so enamored of knock out hits that the tackling skills of many players is actually quite poor and the quality of play diminished. All in all,the idea that football players hit harder than rugby players is purely dependent upon the suit of armor worn by football players. I have played a great deal more football than rugby,and the games are very different in many ways.But their similarities are great as well and the games are made all the more similar when played without the body weaponry.......

  • Milne Craig1

     You are entitled to your opinion but please clarify whether you have played either or both games? As you have decided to 'bake' the quality of one particular game, I would suggest that you are either very short-minded or have played neither style of football to any standard! Footballers as a rule (no matter what variety) are very staunch and determined when defending their abilities and code. Rugby Union & Rugby League teams have less structure regarding match-ups. It is not unusual for a 80kg (175 pound) player to have to tackle a 110kg+ (240 pound + ) player and vice verse. A leveling out is attained as the larger player fatigues and is not substituted while the game is played over 80min. In short, if a league or union team played NFL, they would be beat through lack of skill and knowledge of the sport. As they would be wearing the padding to protect them and would 'match-up' against opposition their size, I doubt that they would be killed. On the other hand, I think it would be a fantastic spectacle to witness an NFL team attempt to play rugby league or union against just an average level rugby team, no pads, no substitutions and continuous running back and forth (similar to basketball only a 100m {109yards} court) for two 40min halves...finally in regards to brain injury, I feel rugby league & union players are only just about to realise the damage they have encountered. This brand of football has existed on a 'you'll be right' attitude. As science improves surely diagnosis and knowledge will point to the fact that years of football has in fact damaged their helmet will prevent injury, rule changes will have little affect as a player will always foul...accept it or not...footballers are a strange combination of toughness, circumstances, ignorance and stupidity!

  • michael

    The rugby comparison is very appropriate. If all the football players played without padding which doubles as armor plating, they would play more intelligently because they wouldn't want to injure themselves. 

    Hard football padding is much more of a weapon than protection.Rather than adding more rules and trying to regulate the play game, take away the protection that enables them to play dangerously.