What are the risks of head injury for players of contact sports such as rugby? Research is increasingly linking head knocks with neurodegenerative diseases later in life. Claire Concannon meets a research team analysing every rugby training session and match across an entire season with high-tech mouthguards.

Grace doesn't think about head knocks when she plays rugby: "If you see your teammates get concussed it can be scary, but when you're playing, I feel like it doesn't cross your mind, you are just more focused on the game."

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But increasingly researchers, clinicians, governing bodies, parents, and players are thinking about it. With increased research linking head knocks with neurodegenerative diseases later in life, and legal proceedings being issued by rugby union, rugby league and football players to various governing bodies, now, more than ever, people want to understand what the risks are, and how to mitigate them.

While to date there has been a gap in knowledge about the risks at a junior level, there are a few studies currently underway in Aotearoa aimed at filling this.

One is working with Grace's team.

Led by Professor Nick Draper at the University of Canterbury, the study aims to follow 40 junior male and female rugby players across every training and game in one full season to work out what their exposure is in terms of number of incidences, and their magnitudes.

Nicole Spriggs, a PhD candidate at Lincoln University, is tracking the girls' teams. She does this by using mouthguards that are moulded specifically for each player using dental scans, and which contain accelerometers. They are set to measure any head acceleration event over eight G - an equivalent to your head wobbling as you bounce on a trampoline. To verify each incident Nicole also videos each training and match.

While Nicole is focused on investigating incidences in female junior players, her University of Canterbury PhD colleague Stefan Henley is focused on doing the same with under 16 boys' teams. All players also do an MRI and neurocognitive test before and after each season that Nicole and Stefan will use to investigate if there have been any changes in the structure and function of the player's brains. …

Go to this episode on rnz.co.nz for more details