New guidelines on limiting heading in football are "extremely welcome", campaigner Dawn Astle says.
Professional players in England will be limited to 10 "higher force headers" a week in training from this season.
"It's one of the most important days in many years of fighting against the business of football," she said.
Astle has previously pushed for research into a link between football and brain injuries, and worked with the Professional Footballers' Association on an advisory basis to help "shape the longer-term neurodegenerative care provision for former members and their families".