I don’t know if this counts as surprising or not, but Science Daily details the changes your brain goes through after something as “mild” as heading a soccer ball:
The study from Scotland’s University for Sporting Excellence published in EBioMedicine is the first to detect direct changes in the brain after players are exposed to everyday head impacts, as opposed to clinical brain injuries like concussion.
A group of soccer ball players headed a ball 20 times, fired from a machine designed to simulate the pace and power of a corner kick. Before and after the heading sessions, scientists tested players’ brain function and memory.
Increased inhibition in the brain was detected after just a single session of heading. Memory test performance was also reduced by between 41 and 67 per cent, with effects normalising within 24 hours.
Whether the changes to the brain remain temporary after repeated exposure to a soccer ball and the long-term consequences of heading on brain health, are yet to be investigated.
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Cognitive neuroscientist Dr Magdalena Ietswaart from Psychology at the University of Stirling, said… “Although the changes were temporary, we believe they are significant to brain health, particularly if they happen over and over again as they do in soccer ball heading. With large numbers of people around the world participating in this sport, it is important that they are aware of what is happening inside the brain and the lasting effect this may have.”