A 19-year-old New Zealand man has died after suffering a serious head injury in a game inspired by the controversial ‘Run It Straight’ trend.

Ryan Satterthwaite from Palmerston North passed away on Monday night after taking part in the full-contact collision game on Sunday afternoon.

Manawatū Police Inspector Ross Grantham confirmed the young man was playing an impromptu tackle game with friends when the injury occurred.

He was rushed to hospital by his mates, but could not be saved.

‘This was an impromptu game among friends, not a planned event,’ Grantham told the NZ Herald.

‘While this is not a criminal matter, police will continue to make inquiries on behalf of the Coroner.’

New Zealand teenager Ryan Satterthwaite died while taking part in a private Run it Straight-style game

Run It Straight has exploded in popularity online despite mounting criticism from health professionals and safety experts

Satterthwaite was not taking part in an organised event, but health experts have celled for the new trend to be banned

The collision game, based on the rising ‘Run It Straight’ phenomenon, involves two people charging at each other with no protective gear.

It has become a social media sensation, with organisers touting it as ‘the world’s fiercest new combat sport’.

One defender and one runner meet at high speed on a narrow 20-metre field.

‘Victory belongs to the one who dominates the collision,’ the sport’s website claims.

Despite the hype, the death has sparked renewed calls for the sport to be banned.

Health professionals say the event ignores decades of head injury prevention research.

Neuroscientist Dr Helen Murray called it an unacceptable risk.

She expressed to the NZ Herald, ‘The event carries a significant risk of head injury. Without efforts to mitigate head acceleration, I cannot endorse it.’

The sport features high-speed collisions between unprotected athletes on a narrow field designed for maximum impact

Professor Patria Hume, an expert in sports science and injury prevention, said the sport is ‘a step backwards’.

‘This is a reckless and dangerous spectacle,’ she said.

‘The science is clear – repeated head impacts increase risk of long-term brain damage.’

Australian neurologist Dr Alan Pearce echoed that sentiment.

‘It’s insanity. You’re removing the skill and strategy and replacing it with blunt force,’ he said.

Run It Straight-style events have recently been staged in Auckland and Melbourne, drawing significant crowds and online attention.

At one recent Auckland event, three of eight competitors left injured, including two with concussion symptoms.

Clips of brutal hits and knockouts have gone viral, fuelling online popularity.

Health experts say the activity poses significant risk of traumatic brain injury and long-term neurological damage

But the death of Ryan Satterthwaite has thrown a sharp spotlight on safety.

Tributes to the teenager have been flowing from friends and family.

‘Rest easy brother Ryan Satterthwaite,’ one wrote.

Another added: ‘So sorry to hear this, especially for the beautiful family I know going through this tragic event.’

Satterthwaite worked at Mainfreight Transport in Palmerston North and was described as kind and humble.

Meanwhile, a planned Run It Straight event in Auckland was cancelled after organisers failed to secure permits.

Local board chair Tauanu’u Nick Bakulich said safety fears played a key role in the decision.

‘The local board opposes this event for reasons of safety,’ he said.

Organisers had not applied to Auckland Council for formal approval.

Auckland Council later confirmed that the event would likely not have been approved.

Run It Straight’s founder, Christian Lesa, said community support remains strong despite backlash.

‘When the community’s there, loving it like I do, it means a lot,’ he said.

But many experts remain concerned about the risks.

Dr Pearce said hundreds of retired footballers now suffer the effects of brain trauma.

‘To take the most violent aspect of sport and glorify it – I was speechless,’ he said.

Despite criticism, some athletes and public figures have endorsed the event.

Former NRL star George Burgess defended the concept, calling it a safe simulation of past combat.

Event spokesperson Billy Coffey said organised competitions involve waivers, pre- and post-medicals, and on-site ambulances.

He claimed it gives former athletes a chance to ‘get off the couch’ and reconnect with their competitive spirit.