Rugby's MND Crisis: What Science Says About Sport, Trauma and Disease Risk

Lewis Moody, the England rugby player who lifted the World Cup, learned this week that he has motor neurone disease. He is 47. The diagnosis arrived as a shock to those who have followed his career, but Moody himself spoke about it with a strange kind of calm. He said he felt capable of doing everything and anything still, and hoped that would remain true for as long as possible. Yet his name joining a growing list has forced a harder question into the open: does rugby itself make you sick?

Two other prominent rugby men have already died from the same disease. Doddie Weir, a Scottish international, died in November 2022. Rob Burrow, who played rugby league for England, died in June 2024. Motor neurone disease is rare—about 5,000 adults in the UK live with it at any given time—but the clustering of cases among professional rugby players has drawn the attention of researchers and the worry of the public. The disease damages the nervous system progressively, making it harder to walk, speak, and breathe as it advances. There is no cure. Scientists do not fully understand why it happens. The lifetime risk for any person is roughly one in 300.

What makes the pattern so troubling is that experts cannot yet say with certainty whether playing rugby causes the disease. The evidence is mixed and often comes from small studies with too few participants to draw firm conclusions. Some research suggests professional footballers may be up to six times more likely to develop MND than the general population, but other studies find no link at all. The uncertainty itself has become part of the story. Researchers in the UK and Italy are now running the largest investigation of its kind, tracking MND rates among thousands of professional footballers over decades, hoping to find clearer answers.

One line of inquiry focuses on head trauma. Last year, Durham University researchers examined 30 retired rugby players who had suffered multiple concussions. They found that the impacts had caused changes in blood proteins that made these players more vulnerable to MND. When the team compared blood samples from the injured players to those from 26 athletes with no history of head trauma, the difference was clear: the concussed group showed more signs of neural damage. The mechanism is not yet understood, but the correlation is there.

Another possibility lies in the intensity of the work itself. Some scientists have theorized that the extreme physical exertion of professional sport generates such intense body heat that it may damage the nerves controlling movement. A 2021 study from the University of Sheffield found that people carrying a mutation in the C9ORF72 gene developed MND earlier if they regularly engaged in highly intense exercise. Professor Dame Pamela Shaw, a neurologist at Sheffield and one of the study's authors, was careful to note that most people who exercise strenuously do not develop motor neurone disease, and that more work is needed to identify the precise genetic risk factors at play.

But the potential causes extend beyond sport. A 2022 study from New Zealand found that exposure to certain pesticides—insecticides, fungicides, and fumigants—raised the risk of MND by up to 70 percent. The same research linked exposure to petrol and diesel fumes to higher risk as well. Heavy metals like lead and mercury have also been associated with amyotrophic lateral sclerosis, the most common form of motor neurone disease. Smoking has been linked to increased risk in several studies, though a 2020 King's College London investigation found the correlation was not as strong as previously thought. Military service, too, appears to carry elevated risk: a 2015 study of 57,000 veterans found they had a 49 percent higher chance of developing MND than the general population, though researchers acknowledged they could not rule out that smoking and other lifestyle factors might explain the difference.

Moody himself has long advocated for mandatory limits on contact time during training and for better financial support for players after their careers end. His diagnosis has given new urgency to those calls. The disease remains poorly understood, and the question of whether certain professions or exposures genuinely increase risk—or whether the clustering of cases among rugby players is simply statistical noise—remains open. What is certain is that five thousand people in Britain are living with a progressive, incurable illness, and that three prominent rugby men have now faced it. The research continues, but for those already diagnosed, the answers may come too late.