Professional footballers in Scotland are to be banned from heading the ball in training the day before and the day after a game.
Clubs are also being told to limit exercises that involve repetitive heading to one session per week.
The new guidelines come after Glasgow University research that showed former footballers were three-and-a-half times more likely to die from brain disease.
Experts believe there could be a link to repetitive heading of the ball.
The Scottish Football Association (SFA) already has guidelines in place limiting heading in youth football, with a ban on headers in training for the under-12 age group.
Scotland was also the first country in the world to have a single set of concussion guidelines for all sports, with the “If in doubt, sit them out” campaign.
The new guidelines are being introduced after consultation with the 50 clubs across the professional men’s and women’s game in Scotland and following an SFA survey of clubs to gauge heading trends.
Clubs are also being told to monitor heading activity in training with the aim of reducing the overall burden of contact.
Dr John MacLean has been the SFA doctor for more than 20 years and was involved in the 2019 field study that highlighted the link between dementia and former professional players.
“While the research continues to develop, what we already know about heading and its effects on the brain suggests that there is measurable memory impairment lasting 24-48 hours following a series of headers, and that brain-related proteins can be detected in blood samples for a short time after heading,” he said.
“Brain scan changes have also been reported in footballers that may be linked to heading.
“Therefore, the goal is to reduce any potential cumulative effect of heading by reducing the overall exposure to heading in training.”