Review of research on the negative effects of contact sports on cognition and brain integrity
Michail Ntikas, Ferdinand Binkofski, N. Jon Shah and Magdalena Ietswaart
9th June 2022
There can be no doubt that regular participation in contact sport yields numerous health benefits and that regular training is necessary to obtain these benefits without any side effects. However, contact sports are also associated with injuries to the musculoskeletal apparatus and have been significantly related to concussion and sub-concussion.
Research shows that sub-concussive head impacts can accumulate throughout an active sports career, causing measurable deficits and changes to brain health. Emerging research in the area of cumulative sub-concussions in contact sports has revealed several associated markers of brain injury. For example, recent studies have discovered that repeated headers in soccer not only cause measurable signs of cognitive impairment but are also related to a prolonged cortical silent period in transcranial magnetic stimulation measurements. Other cognitive and neuroimaging biomarkers also point to the adverse effects of ball heading. A range of fluid biomarkers completes the picture of cumulating effects of sub-concussive impacts. It has been further suggested that an accumulation of these effects can cause significant cognitive impairment later in life.
This review aims to highlight the current scientific evidence on the effects of repeated sub-concussive head impacts on contact sports athletes’ brains, identify the areas in need of further investigation, highlight the potential of advanced neuroscientific methods, and comment on the steps governing bodies have made to address this issue.
The authors conclude that there are indeed neural and biofluid markers that can help better understand the effects of repeated sub-concussive head impacts and that some aspects of contact sports should be redefined, especially in situations where sub-concussive impacts and concussions can be minimised.