'Mission IN-possible': Former rugby pro to attempt world record 200 marathons in 100 days across the UK

Jacko, who lives near Caernarfon, Gwynedd, hopes to raise £1 million for brain injury charities Headway UK and Head for Change with his challenge, titled ‘Mission IN-possible’.

Starting on May 29, the day after his 44th birthday, Jacko will run two marathons every day for 100 consecutive days, covering more than 8,450 kilometres - the equivalent distance of running from London to Los Angeles.

The attempt is expected to break the current men’s world record for consecutive ultra-marathons, but for Jacko, this challenge is about more than records.

In 2013, his professional rugby career was abruptly ended by a traumatic brain injury. The road to recovery was uncertain, and at times, simply returning to normal life felt impossible.

“Everyone thinks this challenge is impossible,” he said.

“But I believe in IN-possible. That belief runs deep - and it’s something my recovery taught me.”

It took seven years after his brain injury for Jacko, who now works as a breath coach with his company Pro Breathwork, to run his first-ever marathon.

Now he is attempting 200 marathons in 100 days - a journey he describes as both physical and spiritual.

The challenge draws inspiration from the Marathon Monks of Japan, whose legendary endurance practice traditionally takes seven years to build toward, culminating in a final year of extreme distance running.

“This feels like my own spiritual journey,” he said.

“My injury took something from me - but recovery taught me how to turn something bad into something good.”

A huge part of Jacko’s recovery involved running and breathwork, tools that helped him rebuild both body and mind. But he is acutely aware that not everyone affected by brain injury has the same access to recovery, rehabilitation, or long-term support.

“I’ve experienced first-hand what recovery can look like - and I’ve also seen what happens when people don’t get that chance,” he said.

The route has been deliberately designed to bring people together across the country. Jacko will run at 25 locations throughout the UK, spending four days at each site, completing the daily distance through 5km and 10km loops.

The loop format allows anyone - runners, walkers, first-timers or experienced athletes - to join him, whether for 5km or further, and take on their own version of the ‘IN-possible’.

Jacko said: “This isn’t just about supporting from the sidelines. It’s about being involved; running your own IN-possible.

“Whether it’s your first 5km or something much bigger - this is about believing in yourself again. And drawing on the support of each other, as I’ve experienced, strength is multiplied when shared.”

Helen Craig, Fundraising Manager at Headway UK, said: “Jacko has firsthand experience of the challenges that come from living with a brain injury. His determination to turn such a difficult period of his life into something so positive is truly inspiring.

“We’re incredibly grateful to Jacko for taking on this extraordinary challenge. His efforts will help us to continue supporting people rebuilding their lives after brain injury, as well as raise crucial awareness of the reality of brain injury, all while bringing communities together across the UK.

Alix Popham, founder of Head for Change, said: “This is an unbelievable challenge, and full credit to Jacko for taking it on.

“Both charities are here to support people affected by brain injury, and that’s what it’s all about.

“We’re really looking forward to joining him for the final couple of days around Newport alongside friends and family.

“Wishing him the very best of luck as he completes this incredible journey.”

You can donate to Jacko’s ‘Mission IN-possible’ here and follow his journey on Instagram at @thebreathrunningcoach

Challenge stats at a glance:

· Challenge: Mission IN-possible – 200 Marathons in 100 Days
· Dates: 29 May – 5 September 2026
· Distance: 8,452km (equivalent to London → Los Angeles)
· Format: Two marathons per day for 100 consecutive days
· Route: 25 UK locations, loop-based for public participation
· Charities: Headway UK & Head for Change
· Fundraising target: £1,000,000
· Goal: World record and awareness for brain injury recovery