Cardiff University researchers are creating the first evidence-backed concussion protocol for women’s rugby, a project that aims to replace the current practice of simply applying a crude 12% reduction on male head impact thresholds – a potentially dangerous gap in knowledge that medical engineers say has left female players without proper safeguarding.
Closing the gender research gap
The study, titled “Towards precise brain health guidelines for women’s rugby”, is being led by Dr Peter Theobald and a team from the university’s School of Engineering and its world-leading Brain Research Imaging Centre (CUBRIC). CUBRIC houses some of the most advanced neuroimaging equipment in Europe, including four MRI systems, MEG and EEG machines, and cognitive testing laboratories. The state-of-the-art MRI scanner used in the study is one of only four such machines in the world.
For the first time, researchers have combined four distinct strands of investigation on the same group of athletes: instrumented mouth guards that measure impact forces, cognitive tests, MRI scans, and computer modelling of brain tissue response. Each player on the Cardiff University women’s rugby team was fitted with a personally moulded, Bluetooth-enabled mouth guard that transmitted real-time data to a tablet held by Dr Theobald and medical engineering PhD student Freya Butcher during training and matches. The mouth guards record the forces transmitted through the teeth to the head and brain, allowing the team to quantify every impact.
In the days before and after games, the same players underwent MRI scans at CUBRIC to detect any structural or functional changes. Their balance and short-term memory were tested immediately after matches so that researchers could later correlate these clinical measures with the head impact data and imaging results. Computer models then simulate how the forces affect different regions of the female brain, which Dr Theobald notes is “softer and more vulnerable to concussion” than the male brain – though he adds that scientists do not yet know whether this translates to a greater risk of subconcussive brain injury over a playing career.
The project’s findings are expected to be published by the end of 2026. Dr Theobald said the goal is not to dissuade women and girls from playing, but “to shed light on the risks so people can make an informed decision”.
‘I feel like I can be part of the change’
On the pitch at Cardiff Arms Park before the annual varsity match against Swansea, the atmosphere was charged. Each Cardiff player collected her individually marked mouth guard case. As the whistle blew, Dr Theobald and Freya Butcher monitored the impact data live on their tablet. Cardiff won 81-0, and two Swansea players retired injured. But before celebrations began, the study participants were led through balance and short-term memory tests – part of the comprehensive protocol that will help the team understand how head impacts correlate with cognitive and physical changes.
Cleo Pallister-Turley, a biomedical sciences student and back for the Cardiff team, has sustained two major concussions from rugby but says the fear of injury has never deterred her. “Girls ask me, ‘aren’t you worried about getting injured?’” she said. “I enjoy the physicality and the intensity. For me, no other sports compare. Any injury would be worth the game for me. The reason I play is for my teammates; all my best friends have come through rugby. The group environment is so accepting and so much fun… it’s love of the game.”
Alongside her teammate Ffion James, a law student, Pallister-Turley spent hours inside the MRI scanner at CUBRIC last week, just before exams and the varsity match. The players changed into magenta hospital gowns and lay inside the humming machine while the Disney film The Incredibles played on a monitor. “I do feel safer knowing there’s going to be more research,” James said. “Before I step on the pitch, I never think I’m going to get injured, it’s only when you see someone down you think about it. I feel like I can be part of the change. Even if it’s a small part, it’s exciting, and hopefully in years to come it will make a change for women in sport and women in rugby.”
James added that the project gives her hope for future generations. “The study helps me be less worried. I always think, if I have daughters, I know that with this research and hopefully more in years to come, they are going to feel safer stepping on to a rugby pitch… my parents were terrified, but hopefully, I won’t have to experience that. I want my daughters to be able to run on to that pitch and think: ‘I’m going to be OK.’”
A wider void in sports science
The Cardiff study is set against a backdrop of systemic underinvestment in research on female athletes. Women now make up a quarter of rugby players worldwide, according to World Rugby, and more than 400 clubs offer the sport to women and girls across the UK – a dramatic increase from the handful that existed in the 1990s. Yet the sport’s growth has not been matched by scientific attention. A 2020 audit found that just 6% of sport science research is specifically about female athletes. A 2023 study showed that more than nine in ten first or lead authors were men, and women accounted for only 13% of all authors.
The consequences of this gap are stark. At the elite level, the threshold used to decide whether a female player should be removed from the pitch for a head injury assessment is simply 12% lower than the figure calculated for men – a blunt adjustment that lacks any female-specific evidence base. “Women’s and men’s rugby are played quite differently, and their brains are different anyway,” said Freya Butcher. “So looking at what happens in the men’s game doesn’t mean we understand the impact on women’s brains and bodies.”
Beyond concussion, the Cardiff team is also investigating how menstruation influences musculoskeletal health, strength and fatigue – an area of sports science that Butcher describes as critically understudied. “It’s still a taboo topic,” she said. “Sometimes the girls have huge bruises on their breasts and sides after games, and they agree that if it was elsewhere, they wouldn’t hesitate to get it looked at. Compression and impact on the breast may be linked to problems lactating and breastfeeding. But right now, female players don’t have adequate protective wear or strategies for dealing with that.”
Broader research elsewhere has highlighted that female athletes may face longer and more complicated recovery times from concussions compared to men, partly due to differences in neck strength and head acceleration. One recent study found that 74% of sampled women rugby players had experienced at least one rugby-related concussion over an average of eight playing years, with being tackled the most common cause. Despite widespread awareness of symptoms, 41% of women players admitted to deliberately failing to report a suspected concussion – behaviour that persisted even after mandatory education programmes.
The legal landscape is also shifting. In 2023, more than 300 former rugby players – including ex-professionals from union and league – filed a lawsuit against the Welsh Rugby Union, England’s Rugby Football Union, and World Rugby, alleging brain damage caused by repeated head impacts. By June 2025 that number had grown to over 1,000 former players pursuing action. Research from the University of Glasgow has found that male rugby players have a 14% higher risk of chronic traumatic encephalopathy (CTE) for every additional year played, and those with long careers face increased risk of dementia and neurodegenerative diseases. What remains unknown, the Cardiff researchers say, is whether the same risk profile applies to women.
Freya Butcher emphasised that the solution is not simple. “It’s not as simple as introducing helmets, or changing the rules of the sport, because then other issues would crop up as players compensated for that.” World Rugby became the first sport to integrate instrumented mouthguards into its concussion protocols in 2024, but those protocols were developed largely on male data. The Cardiff study is designed to provide the female-specific evidence that has been missing for decades – and to give players like Ffion James grounds for confidence that their daughters will be protected in a way their own parents never could.
