'We do love pain a little bit' - Alistair Brownlee and Lucy Charles-Barclay pushing Ironman to the limit

Britain's Alistair Brownlee and Lucy Charles-Barclay are attempting to set Ironman world records

"Pushing myself as hard as I can is just what I do," says Alistair Brownlee with a knowing grin.

He's remembering a day not long after Kenya's Eliud Kipchoge became the first man to break the two-hour barrier for the marathon distance in 2019, a feat that was watched around the world.

Brownlee was sat at a table with fellow triathletes discussing how to push their sport into the spotlight. "It's where the idea of sub seven [and sub eight] came from," recalls the double Olympic triathlon champion.

Just as running a marathon in under two hours was deemed almost unimaginable, similar mythical markers exist in the Ironman triathlon. It's an event for the hardcore - swimming 2.4 miles, then cycling 112 miles, before running all 26.2 miles of a marathon.

Could a man ever complete all of that in under seven hours and could a woman dip below eight? "Firstly we were asking 'is it possible?'" Brownlee, 32, explains. "Then 'what would make it possible?'"

The current men's record of seven hours 35 minutes 39 seconds was set by Germany's Jan Frodeno in 2016, while the fastest woman over the distance is four-time world champion Chrissie Wellington who completed it in 8:18:13 in 2011.

The conversation at the table continued. What would be required apart from the best athletes in the world? Optimum weather conditions, a flat course and utilising the latest technology.

It was an idea from which a challenge was born. Date: 2022. Location: Still unknown.

Two men, Brownlee and half-iron-distance world record holder Norwegian Kristian Blummenfelt, and two women, Swiss former Olympic champion Nicola Spirig and British three-time Ironman world silver medallist Lucy Charles-Barclay, will race head to head in a bid to smash those respective time barriers which have long been considered out of reach.

"It's pretty scarily big," admits 27-year-old Charles-Barclay, "but I've always been an athlete trying to find the toughest test.

"In a similar way to Kipchoge's run, it's showing you what is possible. It's testing the limits of human achievement."

To put the challenge into context, organisers claim the men will need to swim at the speed of Olympic open water medallists, cycle on pace with the fastest Tour de France stage over 100 miles, and run a marathon in under two hours 30 minutes.

Alistair Brownlee (centre) won triathlon gold at London 2012 and Rio 2016, and hopes to defend his Olympic title in Tokyo this summer

As was the case with the two-hour marathon project, this world record attempt will not be official. The four athletes will be allowed multiple pacemakers across each discipline, as well as using wetsuits thicker than normally permitted, adding extra buoyancy and making them faster.

It's this side of the challenge that Brownlee finds most intriguing.

"I'm really interested in the story around this," he said. "Why we've chosen a particular place. Is the water more salty because it's faster? Is the tarmac faster? How can we use the latest tech to go as quick as we can?"

And while he's already roped in brother and training partner Jonny to help him on the course, Charles-Barclay has had plenty of offers from fellow athletes too.

"Currently my best time is eight hours 31 minutes, so in simple terms I need to lose 31 minutes," Charles-Barclay said. "It's going to be very tough but I'm pretty confident. I'm also then going to be looking at how close can I get to [Frodeno's] fastest men's time."

One of the biggest attractions for Charles-Barclay was the equal backing being given to the men's and women's records.

"We're very lucky in triathlon that there's equal coverage as well as prize money. I think this challenge is paving the way for sport in the future," she added. "In endurance events female athletes seem to excel above and beyond the men. I think it's just in our DNA, we can go longer and faster."

Before any of that, both Britons have a big 2021 ahead of them. If the Tokyo Olympics happen as planned in the summer, Brownlee is aiming to be selected to defend his title. Meanwhile, Charles-Barclay has her sights set on gold at October's Ironman World Championships in Hawaii.

Plenty of time to mull over the lung-busting challenge that awaits next year, which is being backed by The Phoenix Foundation, a Polish not-for-profit organisation that supports sporting participation among young people.

"I think there is just something about British triathletes being crazy challenge seekers," Charles-Barclay chuckles. "We do love pain a little bit."

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