Great Britain’s Sarah Webster made history on Saturday at the IAU 24-Hour World Championships in Albi, France, setting a new women’s 24-hour world record with a distance of 278.622 kilometers (173.127 miles).
The 46-year-old, who lives in East Sussex and originally hails from the Isle of Man, surpassed the previous mark of 270.363 km (167.996 miles) set by Japan’s Miho Nakata in 2023. Webster’s effort added more than 8 kilometers (over 5 miles) to the existing record, a rare margin in a discipline where records are often broken by just a few hundred meters.
Webster’s run took place on a 1.5-kilometer loop, where she completed 185 laps and one partial lap in the final minutes. Her average pace worked out to about 5:11 per kilometer (8:19 per mile), including any aid stops or short breaks over the 24-hour period.
Though she’s relatively new to the ultrarunning scene, Webster’s been quietly building a strong resume over the past few years. In 2023, she won the Northern Ireland and British 100k Championships in 7:03 and took bronze at the IAU 50k World Championships.
She followed that with another podium at the 2024 IAU 100k World Championships and ran 243.393 km (151.237 miles) over 24 hours earlier this year to qualify for the World Championships in Albi.
Saturday’s race wasn’t without its challenges. At the six-hour mark, Webster was still around five kilometers behind Nakata’s world record pace. But by halfway, she had caught up. From there, she ran consistently through the night, slowly pulling ahead.
With six hours to go, she was nearly 10 kilometers ahead of the record pace. She eventually broke the record with just over an hour remaining, then kept running to add another 7 kilometers before the 24 hours were up.
“I just kept ticking off the laps,” Webster told local media after the race. “I had no idea how far I could go, but everything just came together.”
Webster’s performance earned her not just the world record but also the 2025 IAU world title, besting a field of 161 women. It marks the latest chapter in a late-blooming but fast-rising running career, one that began only a few years ago, after she had already competed in triathlon and cycling.
It’s also a major moment for British ultrarunning. While the UK has a long history in the sport, world records at this level have become increasingly rare. Webster’s run may help bring more visibility to an event that remains niche even within the ultrarunning world.
