Concussion experts encourage CFLers to wear Guardian Caps, but say athletes shouldn't feel 'immortal'

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.