New research into heading a football has identified "significant" changes in brain function from routine practice.
The study from the University of Stirling in Scotland is the first to detect direct effects from what is a routine and constant part of the sport.
Researchers tested a group of 19 players, making them head a ball fired from a machine that simulated the velocity of a corner-kick 20 times.
Brain and memory function was tested before and immediately after these heading sessions, after 24 hours, 48 hours and after two weeks.
Increased inhibition in brain function was detected after just a single session of heading. Memory test performance was also reduced by between 41% and 67%, with these effects eventually normalising within 24 hours.
Cognitive neuroscientist Dr Magdalena Ietswaart 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 football 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."
Dr Angus Hunter, from the Faculty of Health Sciences and Sport, said: "For the first time, sporting bodies and members of the public can see clear evidence of the risks associated with repetitive impact caused by heading a football.
"We hope these findings will open up new approaches for detecting, monitoring and preventing cumulative brain injuries in sport. We need to safeguard the long term health of football players at all levels, as well as individuals involved in other contact sports."
The findings come after increasing concerns that players' brains are damaged by repeatedly heading the ball.
Former England and West Brom striker Jeff Astle died in 2002 at the age of 59, suffering from early on-set dementia, which a coroner found was caused by heading footballs. Astle's subsquent cause of death was confirmed as "industrial disease".
EmoticonEmoticon