Canadian doctors and brain injury experts believe Canadian Football League players should be encouraged to use Guardian Caps whenever they have the opportunity, but say the technology does not mitigate the risk of concussion.
The CFL announced on May 15 that players will be allowed to wear Guardian Caps — protective soft-shell helmet covers — during games this season as part of a new series of health-and-safety measures. The league also mandated mouthguards, becoming the first professional league in North America to do so.
Dr. Charles Tator and Dr. Carmela Tartaglia — leadership members of the University Health Network’s Canadian Concussion Centre, a team of world leaders in brain injuries, imaging, genetics, clinical care, neuropsychology and psychiatry — both said they haven’t seen enough data to convince them that the soft-shell cap can protect against concussions.
Dr. Blaine Hoshizaki, director of the Neurotrauma Impact Science Laboratory at the University of Ottawa and internationally-recognized for head and brain injury research, went so far as to say no technology can.
Dr. Ravi Menon, world-renowned for his work in functional magnetic resonance imaging (fMRI), and Dr. Tartaglia both said the cap could possibly blunt the more severe blows to the head, but can’t help with subconcussive impacts, also known as a subconcussion, which is any impact that doesn’t result in a diagnosed concussion.
Their claims are consistent with results from a 2023 peer-reviewed study from Stanford University, published in the Annals of Biomedical Engineering. The study reported reduced impact on the soft shell compared to a bare helmet when tested in a laboratory. However, on-field results reported no significant differences between the soft shell and the bare helmet.
With his findings researching brain impacts on athletes at Western University, Dr. Menon said these subconcussive blows can be just as bad as the real thing.
“Subconcussive hits, over multiple seasons, give rise to exactly the same damage we see in an explicit concussion,” Dr. Menon said.
Guardian chief executive officer and founder Erin Hanson told CBC Sports the cap aims to reduce impact, not concussions. She said concussions are “so individualized” that the soft shell can’t reduce the risk of a player getting a concussion.
It’s also written on Guardian’s website that “no helmet, practice apparatus, or helmet pad can prevent or eliminate the risk of concussions or other serious head injuries while playing sports.”
But Hanson said there’s been research done that supports the cap being beneficial for football players in reducing impact to the head.
According to ESPN’s Kevin Seifert, the National Football League released data in 2022, reporting summer training camp concussions among players mandated to wear the cap (linemen, tight ends and linebackers) decreased by over 50 per cent from the average between 2019 to 2021. The previous three-year average was 23 concussions, which decreased to 11 in 2022 — six of which were from face mask contact, which is not covered by the cap.
The CFL also said it saw a 42 per cent decrease in concussions during the 2023 training camp period when players wore caps, among other preventative measures, compared to past years without the soft shells.
Dr. Hoshizaki isn’t convinced the CFL’s figures were completely due to the caps, instead believing the decrease is more likely due to a combination of safety measures the league implemented for practices by then.
Other research supporting the caps’ impact reduction includes a 2021 peer-reviewed study, published in the Annals of Biomedical Engineering, that reported the Guardian Cap helped reduce head impact severity.
Dr. Tartaglia and Dr. Menon both shared worry over a heightened reliance on technology.
They believe that, as athletes wear more equipment and use newer technology, they may compensate and take on more risk.
Hanson, however, said she has heard from coaches who’ve said players who wear the cap, and see another player across from them wearing it, have become more conscious of impact on the field.
“[Coaches] were afraid that, ‘oh man, this guy’s gonna think that he’s concussion-proof and he’s gonna hit harder.’ And they said it’s the opposite,” Hanson said.
“They look across the line and see it; it’s a reminder. It’s like, ‘oh my God, I got that goofy thing on my head, I’ve gotta keep my head up and out of the way.'”
As long as players don’t feel infallible and take on additional risk, all four doctors said there’s no harm in using the Guardian Cap — but add that they’d like other measures to be prominent as well.
The doctors said they’re pleased with the “spotter” measure, used in both the CFL and NFL, which includes having an injury spotter on the sideline to watch for any potential injuries, including head impacts.
In 2024, the CFL introduced a new injury spotter assistant position in their league command centre to oversee video and communication technologies.
Dr. Tartaglia said spotters could be helpful for limiting further risk for potentially-concussed players on-field.
Dr. Tator is particularly impressed with the NFL’s updated spotter measures, especially after he watched Miami Dolphins quarterback Tua Tagovailoa sustain multiple concussions during the 2022 season.
“They’ve gone a long way at the NFL level to detect serious concussions and also serious heart injuries. … They’ve taken it seriously,” Dr. Tator said.
Whether players wear the Guardian Caps this season or not, experts believe the best way to reduce concussions in contact sports is to reduce contact rather than solely improve technology.
“We’re not woodpeckers,” Dr. Tartaglia said.
“You only have one brain.”
