Why it pays to wait before playing contact sport

With growing awareness of the link between head injuries in sport and degenerative brain diseases, there’s a call to limit or even ban contact sports in young children.

Dr Helen Murray is a leading researcher in New Zealand neuroscience, focusing on concussion and long-term brain injury in sport. As a research fellow in the Centre for Brain Research, she works at the intersection of brain science and sport. Her research helps the global effort to understand Chronic Traumatic Encephalopathy, or CTE, a disease linked to repeated knocks to the head.

Murray’s sporting background drives her passion. She has represented New Zealand in ice hockey and inline hockey, and she has experienced concussion herself. Seeing teammates suffer both minor and serious head knocks motivated her to focus on the long-term effects of repeated trauma. Her lab now pays close attention to microtrauma, the small hits that build up over a career in contact sports.

This focus also feeds into her public outreach. In the University’s “Expert Tips in Two Minutes” series, she shares research-evidenced advice on how parents and coaches can protect children from harm. The series is hosted by Comms/Arts third-year student Joelle Ireland. 

“One of the best things we can do is delay children’s involvement in contact sport until they are older,” Murray says. “By starting contact later, we can reduce the overall lifetime exposure to head impacts which is the strongest risk factor for CTE”.

Brain samples

Murray’s work includes examining dozens of markers in postmortem brain tissue to identify new avenues for early diagnosis and prevention of the disease. This allows researchers to gather significantly more information than previously possible.

Her research explores how repeated head impacts, not just diagnosed concussions, can set off inflammation and blood vessel damage that may lead to CTE.

She has also worked with PhD student Chelsie Osterman, studying brain tissue from former rugby players and comparing it with samples from people with Alzheimer’s disease and healthy donors. They found specific clusters of inflammation around blood vessels in brains with CTE. The findings suggest that support cells in the brain, called astrocytes, may play a key role in how the brain responds to repeated impacts.

This study, published in Acta Neuropathologica in March 2025, suggests that inflammation may serve as a potential biomarker for detecting CTE in living individuals. It was a collaborative effort between Murray’s team at the University of Auckland and her international collaborators at the Australia Sports Brain Bank and Boston University. The work points to inflammation as a possible biomarker that might one day be used to detect CTE in living people through MRI scans or blood tests.

Murray also contributes to the Sports Human Brain Bank initiative, which collects brains from former athletes for research into traumatic brain injury. This resource connects the University of Auckland with an international network of concussion research groups.

Other research involves working alongside the very sports affected by the likes of CTE. In September 2025, a study co-led by Dr Stephanie D’Souza from the COMPASS Research Centre and Dr Ken Quarrie from New Zealand Rugby found that former first-class rugby players had a 22 percent increased risk of developing any neurodegenerative disease, and a 61 percent increased risk of developing Alzheimer’s disease specifically.