Image Credit: UCLA

After decades of research in the field, the US National Institute of Health (NIH) has acknowledged a causal link between repeated mild incidences of head trauma to developing of chronic traumatic encephalopathy (CTE). In the last 15 years, there has been much debate about whether sports that involve repetitive contact (e.g., hockey, American football, soccer, rugby, MMA, boxing etc.) cause progressive, irreversible degeneration in the brain. This is the first time that NIH has acknowledged the causal link between repetitive blows and development of CTE.

CTE is a complex brain disorder that involves progressive neuroinflammation; individuals with CTE exhibit impulsiveness, cognitive impairment, explosiveness and emotional liability (Katz et al, 2021).  The clinical diagnosis of this condition is evolving, and it is confirmed only post-mortem by more definitive pathological criteria.

So, there is increasing evidence that repetitive concussions, repetitive blows to the head, neck, or body (you can get a concussion even if something does not touch your head, think whiplash from car accidents, tackling in football, hockey etc.) can lead to progressive degeneration in the brain. Having said that, repetitive blows is not the only cause for developing CTE. Researcher in the field mostly agree that developing CTE has genetic and epigenetic risk factors, but the repetitive blows to the body or head is a major environmental risk factor (Mavroudis et al, 2022).

If you are a soccer player, try not to hit the ball with your head (maybe they should make a new rule and allow use of hands for Corners? Or disallow using of heads altogether?), if you are a boxer and you get hit many times in your upper trunk/head, maybe it’s time to rethink/reconsider and take better care of your brain? As for other sports such as American football, rugby, hockey it is more complicated. Contacting and bumping into each other is in the core of these sports. Maybe some rule changing will go a long way? For many, playing contact sports is a passion and some people may be willing to take the risk (especially there is so much at stake in elite contact sports).  There are no easy solutions, but brain health should be paramount for both sport and non-sport populations.

References

McAllister, T.; McCrea, M. Long-Term Cognitive and Neuropsychiatric Consequences of Repetitive Concussion and Head-Impact Exposure. J. Athl. Train. 2017, 52, 309–317

Mavroudis, I., Kazis, D., Chowdhury, R., Petridis, F., Costa, V., Balmus, I. M., ... & Baloyannis, S. (2022). Post-Concussion Syndrome and Chronic Traumatic Encephalopathy: Narrative Review on the Neuropathology, Neuroimaging and Fluid Biomarkers. Diagnostics, 12(3), 740.