An American neuroscientist has warned of more looming deaths as the controversial collision sport “run it straight” is due to make its debut in the United States.

The same organisers who brought the physical social media trend to New Zealand shores in May are set to embark on a two-week tour of America’s West Coast from November 18, with six trials in Las Vegas, Salt Lake City, Santa Monica, Irvine, Seattle and Austin.

The Australian-based Runit League held two trial nights at Auckland’s Trusts Arena and planned to host a final event, but ongoing backlash from neuroscientists and council workers regarding the safety of the sport – as well as the death of 19-year-old Ryan Satterthwaite in a copycat event of the social media trend in Palmerston North – prompted organisers to shift the final to the Middle East.

The winner of the A$200,000 ($232,000) final in Dubai later told the Herald he apologised for his role in influencing youth to take part in the controversial activity, leading to Satterthwaite’s death, in an exclusive interview.

The origins of run it straight date back to the late 1940s, when it was invented by the coach of college football team the Oklahoma Sooners, Bud Wilkinson.

The “Oklahoma drill”, as it was dubbed, involved two players wearing protective pads and helmets running full speed at each other with the sole purpose of knocking their opponent over. It was adopted by college football and NFL teams across the US before it was officially banned in 2019 in an effort to reduce concussions.

American-based charity the Concussion Legacy Foundation’s CEO, Dr Chris Nowinski, told the Herald it was “unfortunate” that run it straight had infiltrated the US market.

When the Herald visited the second Runit League Auckland trial night in May, three of eight competitors were forced to retire with injures – two of whom showed signs of a concussion. Photo / Mike Scott

“I’m concerned that the people who would sign up for this don’t understand what traumatic brain injuries or chronic traumatic encephalopathy (CTE) can do to their lives.

“This is the kind of idea that could only take root because we have poor awareness of the long-term effects of repeated hits to the head.”

Nowinski, a former professional wrestler for the WWE, called the sport a “backwards step in human development” and “one step away from throwing people into a cage with lions”.

“The more this sport succeeds, the more people will die. I think it’s an easy statistical prediction to make based on the activity in which they are engaging.”

He said in a social media world, there was a business model because the product sounds and looks interesting to a teenage market.

“That’s in part because a teenager’s frontal lobe is not developed enough to understand the long-term consequences and think about the long-term ramifications of this activity ... It’s up to the older, wiser community to not only discourage this, but raise awareness that this is not a healthy activity.”

Ryan Satterthwaite, 19, died after sustaining a head injury in a copycat "run it straight" game in Palmerston North.

Nowinski said if the trials are successful over the coming weeks, there would likely be movements to discourage or ban run it straight in the US.

“I guess we’ll just wait to see if we’ve taught Americans about concussions and CTE well enough that they reject it.

“If the organisers want to sleep well at night, I at least hope they are warning the participants very clearly that this activity may kill them, may cause them a permanent brain injury and if they participate enough times, put them at risk for CTE.”

The Runit League did not wish to comment on its American tour when approached by the Herald.

The six trials, sponsored by controversial online gambling company Stake, tout a US$40,000 ($70,000) prize pool – with $8800, $1800 and $880 on offer for first, second and third placed competitors respectively at each location.

When the Herald visited the second Runit League Auckland trial night in May, three of eight competitors were forced to retire with injuries – two of whom showed signs of a concussion. Several others have suffered serious head injuries in their other events.

During the organisation’s Dubai final in June, ugly footage emerged of former NRL veteran and Kiwis representative Kevin Proctor suffering a serious head injury and an apparent seizure after a collision.

Former NRL veteran and Kiwis representative Kevin Proctor suffered a serious head injury and an apparent seizure after a collision during a "run it straight" final in Dubai in June. Photo / Kick

A livestream of the event showed Proctor, who was tackling, drive his right shoulder into Australian social media influencer Jordan Simi’s chest as the pair ran full speed at each other.

The former NRL Premiership-winning Melbourne Storm and Gold Coast Titans second-rower was thrown into the air from the force of the collision and fell heavily on his side before his legs started involuntarily twitching in the air and his arms went stiff.

The NFL did not respond to the Herald’s queries on the arrival of Run it Straight in America and the NFL Players Association declined to comment.

Speaking to the BBC in June, one of the Runit League’s seven co-founders, Brandon Taua’a, said there were ongoing talks with potential US investors, including a contact linked to American podcaster and UFC commentator Joe Rogan.

Taua’a told the masthead it would “definitely help” the organisation and sport build a presence in America.

The Runit League has amassed over 600,000 followers across its social media pages, with its videos being viewed hundreds of millions of times.

Sports Medicine New Zealand national chairman Dr Stephen Kara earlier told the Herald the biomechanics of the sport’s collisions were “comparable to severe car crashes”.

“This activity doesn’t just endanger participants, but makes a mockery of the considerable effort and investment contact sports have made on impact-readiness training, brain injury awareness, reporting and management, all in a bid to ensure the safety and wellbeing of athletes.

“[It] is not a sport. It is jousting without sticks and, whilst that may have been a sport in medieval times, it has no place in today’s sporting arenas.”

The Herald reported in July that the New Zealand Government had sought advice on “run it straight” and other emerging combat sports, with a decision on their futures in New Zealand set to be reached at the beginning of 2026.

Official Information Act documents showed an “initial meeting”, led by Sport New Zealand and involving the New Zealand Police, the Ministry of Justice, the Sport Integrity Commission, ACC, WorkSafe New Zealand and the Department of Internal Affairs, took place on June 16.

The Herald understands further meetings were set to be held and an outcome would be reached by early next year.

Benjamin Plummer is an Auckland-based reporter for the New Zealand Herald who covers sport and breaking news. He has worked for the Herald since 2022.