After more than a decade of boxing, Sam Dwyer knows he is taking a risk. "I think it's a bit of cognitive dissonance," he said. "There's nothing you do in life that doesn't have risk … but obviously protecting yourself is very important." However, a new analysis of head knocks by Central Queensland University's (CQU) Ragnar Purje found that even low-level impacts on the head in sports like boxing can reduce neural function. The analysis also highlighted the particular risks of head knocks for children, with even sub-concussive impacts having long-term consequences. Dr Purje's colleague, CQU's head of educational neuroscience Ken Purnell, said experts wanted to make sports "smarter, not softer". "It's not about banning boxing or karate or soccer or whatever else," Professor Purnell said. "It's really more about awareness … all thinking about prioritising that safety for the brain, so the sport can be thriving." A growing sport A professional boxer, promoter and gym owner from Mount Gambier in South Australia's south-east, Dwyer started in the sport 13 years ago. "It's opened up a whole world of opportunities for me," he said. During that time, he started his gym, began running events, and has seen increased participation and attendance. "When I moved back to Mount Gambier, I was one of a handful of amateur boxers. Now we've got 20-odd getting ready to fight out of the gym." Dwyer said the motivations behind people taking up the sport varied, with some never intending to get hit. "All of our technical and general classes are non-contact, so there's a lot of people that do it just for the fitness and community side," he said. "Probably 75 per cent of our gym members are just here for fitness." Sub-concussive blows add up Professor Purnell said that as the popularity of combat sports had grown in recent years, so had the knowledge about the impact on the brain. "Even if a knock to the head doesn't cause concussion, it can contribute to long-term brain changes, especially in young athletes where their brains are still developing." Professor Purnell said the sub-concussive blows could add up, causing symptoms such as mood changes, brain fogginess, irritability and more. Dwyer said that while he had so far avoided issues with head injuries, many boxers had changed the way they train. "Back when I started, we'd do a lot more sparring than we do now," he said. "We do a lot more skill work and the sparring we do, unless we're coming into comp, is very light. Making sports 'smarter' on head injuries Professor Purnell said it would be impossible to remove head contact from sports where it was ingrained in the culture, such as combat sports. But he said administrators needed to look at ways to minimise risks across all sports. "We're smart about when we get in a car that we wear our seatbelt," he said. "So what can we do, whether it's soccer or hockey or netball or whatever, to reduce the possibility of it occurring and then to help if and when it does?" he said. Beyond the sports themselves, Professor Purnell said the "magic four" elements of connectedness with other people, good nutrition, decent sleep and exercise could help maintain a healthy brain. "If you're in that period where you've had a few of these knocks, but you do these things, they help to mitigate against some of those more adverse impacts," he said. "The moment something starts to interfere with your daily life, you know that's when you really need to take some action to reduce that."