New guidelines on heading are being introduced to Scottish football in a bid to help protect players.
It will see training exercises which could involve repeated heading limited to no more than once a week.
Such exercises should not take place the day before a match or the day after, the guidelines state.
Clubs have also been told to plan and monitor heading activity in training to reduce the overall heading burden.
The guidelines are being introduced by the Scottish FA and comes in response to concerns over possible links between heading/head injuries and neurodegenerative disease.
Following introduction of the guidance, the Scottish FA will work with clubs, coaches and players to monitor progress.
A study was conducted by the SFA to understand current heading practices, with 50 SPFL and SWPL clubs surveyed.
More than 70% of managers and coaches were found to support the introduction of heading guidelines.
Over 64% of players also stated their belief that heading should be limited in training.
In 2020, the SFA introduced ‘heading guidelines’ for children’s and youth football in Scotland.
Ian Maxwell, SFA chief executive, explained that the guidelines will be implemented with immediate effect.
“The Scottish FA said at the time that this research should shape the thinking in the adult game not just domestically but across the world,” said Maxwell.
“I am grateful to everyone in the professional game – clubs, coaches and managers, and players – for contributing to the latest research which has culminated in these new guidelines.
“It is our intention that these guidelines will be embraced and implemented with immediate effect.
“The publishing of today’s guidelines represents our ongoing commitment to player welfare.”
Dr John MacLean, Scottish FA chief medical consultant, indicated that brain scan changes have been reported in footballers that may be linked to heading.
“It is important to reiterate that while the FIELD study was not designed to identify the causes of this increased risk, both head injury and heading have been suggested as possible contributing factors to the neurodegenerative disease,” said MacLean.
“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 heading.
“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.”
Andy Gould, Scottish FA chief football officer, added: “There already exists a lot of data around in-match heading but this latest research has been invaluable in understanding the extent of heading load within the training environment.
“I am grateful to the clubs, managers and players for providing us with the information and perspectives required to facilitate an informed and data-driven discussion which has culminated in the publication of guidelines designed to protect the safety and wellbeing of our players.”