Football does already have restrictions around heading.
The Football Association has phased out deliberate heading in grassroots football matches for children aged 11 and under.
It has also issued guidance recommending limits on heading during training of no more than 10 headers per week at amateur level.
In the professional game in England, clubs have been advised to limit players to 10 “high force” headers a week in training.
Scotland has gone further, banning heading in training on the day before and after matches in the professional game.
However, campaigners such as Dr Judith Gates, founder of Head Safe Football, believe that voluntary guidance is not enough.
“What we are finding is that coaches and parents don’t know of the guidance, or the ban. Or they do not know why it exists,” she told BBC Sport.
“There needs to be greater clarity and greater specific restrictions in order to protect players of today and tomorrow.”
Dr Gates, whose husband the former Middlesbrough player Bill died with CTE, a degenerative brain disease associated with repeated head impacts, accepts that enforcing a legal limit would be challenging.