Mouthguard technology will be used to measure the impact of different types of headers at two Premier League clubs, as English football prepares to introduce guidelines around heading in training in the professional and adult game for next season.
Here, the PA news agency looks at the study in more detail.
What's the background to this?
A working group made up of all of English football's major governing bodies was set up last year to consider heading guidelines in elite and adult football training. Guidelines are already in place at under-18s level, with coaches of under-11s advised not to make heading part of any training session.
How does the technology work?
The technology has been developed by Sports & Wellbeing Analytics (SWA) and the intention in football is for players to wear a retainer, rather than the mouthguard which has been used to date in rugby and other sports.
Explaining why a mouthguard is the best measuring device, SWA executive director David Allen told PA: "The upper jaw is the only part of your body that is directly connected to your skull. And when it's directly connected to your skull, inside your skull is housed your brain.
"We can monitor and manage the G-forces that happen once the ball hits the head. If people are doing heading practice we're able to look at the cumulative factor. If they're practising corners and they're running in to head the ball or they're doing it from a standing position, we're able to measure the impact of the ball and the head put together."
Data is then relayed to the touchline in real time.
Who is taking part?
It will be Liverpool's under-23s and under-18s men's teams and senior women's team alongside Manchester City's under-18s men's team and senior women's team. The devices will only be worn in training, not in matches.
What are the timescales around this?
There has been pressure on the game's leaders to move fast on this, as there are concerns from head injury campaigners like Dawn Astle and Chris Sutton that while research is conducted, more damage is being done to the brains of current players. The Premier League said on Friday it was expected that the heading guidelines would be in place for the start of next season, and Allen told PA that SWA hoped to complete its study by the end of the current campaign.
What will the football authorities do with the findings from this study?
The idea is to use the findings to make the heading guidelines for senior professional and adult football as specific as possible, and may lead to some types of heading being more restricted than others, depending on which are found to have the most severe impact on the head.