A recent study of youth football players has confirmed that smaller blows to the head can accumulate over the course of a season to create cognitive impairment.
Sanford Research in Sioux Falls, S.D., monitored 15 American male youth football players under the age of 14 for the study, using neuro-technology that tracks brain vital signs developed by HealthTech Connex Inc. in Surrey, B.C. The study found that players who were not diagnosed with concussions still underwent changes to cognitive processing related to subconcussive impairments by the end of the football season.
The research was conducted by Dr. Thayne Munce in South Dakota and Dr. Shaun Fickling, based in Vancouver, was the lead author of the study
"The changes that they experienced were highly related to the number of head impacts they were exposed to, whether that was by the actual number of head impacts recorded, or just by the number of minutes that they participated in," said Fickling.
A subconcussive impact is a mechanical force transmitted to the brain below the threshold for a diagnosis of an acute concussive injury. The effects of these low-magnitude impacts may not even be noticeable to the player or to observers on the sideline.
The youth football study replicated and built on a previous study of junior-A and bantam youth hockey players conducted in Minnesota with the Mayo Clinic. Those results were previously published in the article "Brain: A Journal of Neurology and Brain Communications."
"Repeating the study design with younger football players, and seeing the same results in a completely independent study was really, really impactful for me," said Fickling. "Just to see how consistent this relationship is becoming."
Fickling said that he is often asked by parents what these studies mean for the safety of their children who participate in contact sports like hockey and football.
"The caveat here is that this is a snapshot in time, it's not necessarily the full story. We're not looking at these players as they recover over the off-season," said Fickling. "The more exposed we are to head impacts and repetitive head impacts, the greater the likelihood of some sort of cognitive changes happening in the brain.
"I think the take home message here is to try and control head impact exposure as much as possible with the caveat that this is still very much a field that's being explored."
Fickling said the next areas of study will be to broaden the field to different age groups, genders, and sports. A larger and more diverse sample size will help researchers better understand the findings, even if it only confirms previously recorded data.
Beyond that, looking at the year-round effects of subconcussive head impacts will be important.
"To continue to look at changes occurring after the season has ended," he said. "So is there a measure of recovery in the off-season, when athletes or players are no longer exposed to head impact?"
Fickling also said that doing more assessments over the course of a season — rather than just assessments at the start and end of it — will help create a longer narrative of how the brain reacts and heals from repeated subconcussive impacts.
This report by The Canadian Press was first published March 7, 2022.
John Chidley-Hill, The Canadian Press