Dirga, Digital Explainer Explainer - A 19-year-old from Palmerston North died recently playing a version of the controversial violent 'Run It' contest. knock on the head kill? Here's what you need to know about brain injuries. What is Run It? An Australian creation that has taken off in Aotearoa thanks to social media, 'Run It Straight' is a combat sport. field, a ball runner and defender charge at full speed toward one another without helmets or safety gear. The participant who "dominates" the contact is deemed the winner. Events held in New Zealand recently offer cash prizes, including a $200,000 prize advertised for the winner of the final. sporting groups and health experts have condemned the contests, including NZ Rugby and NZ Rugby League. What happened to Ryan Satterthwaite? The 19-year-old Palmerston North man Monday night in hospital, after suffering a catastrophic head injury on Sunday, 25 May playing an unofficial Run It-style game with friends. Police said it was an unspectacular tackle that led to the Manawatū area commander inspector Ross Grantham told RNZ's Checkpoint that Ryan's head didn't hit anything hard during the tackle. just an impromptu event with some mates that got together and the two men run towards each other, and from that collision, this young man Ryan has received such a terrible injury that it's been fatal," Grantham said. doesn't look like his head has hit anything hard, hasn't hit the ground, or his mate's body or head. It's the movement that has caused this injury." Satterthwaite's family have urged people not to take part in the game, with his uncle calling it "the most stupid thing I've ever The death comes after two other men were knocked unconscious and required medical attention during a competition at Auckland's Trust Arena. What happens to the brain with this kind of impact? People don't understand how fragile the brain really is, said Dr Helen Murray, a neuroscientist and senior research fellow at the University of Auckland's Centre for Brain "The main thing to think about is our brain is essentially floating in cerebrospinal fluid inside our skull, so every time you bump the front of your skull, the brain is moving around in your head. "It's sort of like an egg in an eggshell - if you shake it, you damage what's inside. It's a very delicate structure." to the head can cause bleeding or harm the careful infrastructure inside our skulls. "All of those delicate folds of the brain are stretching and twisting, and that can cause damage," she said. "Blood is not supposed to be in direct contact with brain tissue." Bleeding on the brain can cause problems such as a stroke. exact details of Satterthwaite's injuries have not been revealed, but sudden death from a brain injury can also occur because it regulates most of our body functions. If the brain stem - which connects your brain to the spinal cord - is affected, it can result in critical "Your brain stem is really responsible for a lot of what we call homeostatic functions, the things that keep your body alive," Dr Murray said. think about your heart beating, you don't think about your breathing or your blood pressure, but your brain is always making that happen all the time." Several people are believed to have suffered concussions - a brain injury caused by a blow to the head - during Run It activities. Chief executive of the Headway brain injury support charity Stacey Mowbray recently told RNZ she found Run It Straight video footage "horrendous and really distressing". "We refer to concussions as the invisible injury, so you don't have to see anything initially to have had one." hurt and not realise it right away? Even if the injury isn't immediately fatal, brain injuries can also develop over years. "Your brain is so precious and a brain injury affects, not only your life, but your friends, your family and the people around you, and it can last a long, long time," Dr Murray said. Haven't there been concerns about brain injuries in contact sport for a Absolutely, and the particularly stark nature of Run It events has drawn attention to long-standing research about sports players developing life-changing Brain injuries in sport cost New Zealand every year. Some former athletes have been diagnosed with Chronic Traumatic Encephalopathy or CTE, a progressive brain disease that can cause dementia-like symptoms. Former All Black Carl Hayman has spoken out about with the disease, which he was diagnosed with in his Dr Murray is one of New Zealand's leading experts on CTE and an ice hockey player herself. She said contact sports can be played safely, but events like Run It lacked safeguards. "There are some unique factors in this Run It event that just make it a really, really heavy risk - the fact that no-one is trying to avoid a collision, for "You instantly have this high-force component, the lack of regulation, people just kind of doing this without safe tackling technique. Someone's judging the collision, so there's an incentive for high "So many sports have been doing a fantastic job about learning to play more safely... but this is a big step backwards." What is the future of Run West Auckland's Trusts Arena cancelled plans to host the final event for the Runit Championship League after holding trials there. "Safety of all participants at our venue is paramount and this activity presented safety considerations that we could not overlook," Trusts Arena's general manager of community engagement Lynette Adams told the New Zealand Herald. Should it be After Satterthwaite's death, police said it was not considered a criminal matter, but they would continue to make inquiries on behalf of the "We need people to stop participating in activities where the intention is to hurt someone," AUT professor of human performance Patria Hume told the Science Media Centre. "Why is this not considered Sports and Recreation Minister Mark Mitchell is seeking advice on what could be done about the RNZ's Nine To Noon last week he had asked Sport NZ for advice to see if there was anything that could be done at a government level. Mitchell said it would likely require a response from several © Scoop Media