The Scottish FA is to ban heading on the days immediately before and after matches as a result of new research into brain disease in retired soccer players.
Clubs were also advised to limit repetitive heading exercises to once a week.
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Scotland has already banned heading in training for Under-12 players.
"Training exercises which could involve repeated heading should not take place on MD-1 (the day before a match) or MD+1; this includes activities such as crossing and finishing and set piece practice," guidelines published on Monday said.
A 2019 study on the Influence on Lifelong Health and Dementia Risk (FIELD) undertaken by Glasgow University and supported by the Scottish FA found former professionals were at more risk of dementia.
The Scottish FA said it had carried out new research in conjunction with Hampden Sports Clinic into the impact of heading in training in the professional men's and women's adult game.
The FA said 70% of managers and coaches were supportive of heading guidelines being introduced while 64% of players believed heading should be limited in training.
"The possible link between heading, head injury and neurodegenerative disease in football will continue to be the subject of scientific research," the Scottish FA said.
"These guidelines will continue to be reviewed in the light of any new evidence."