Jo Zakrzewski Sets 48-Hour Running World Record of 411.458 Kilometers (255.668 Miles)

Jo Zakrzewski of the U.K. set a 48-hour world record of 411.458 kilometers (255.668 miles) at the Taipei Ultramarathon the weekend of February 10-12, 2023.

By on February 12, 2023 | Comments

The United Kingdom’s Joasia “Jo” Zakrzewski set a new women’s 48-hour world record by running 411.458 kilometers (255.668 miles) at the Taipei Ultramarathon this weekend.

Zakrzewski broke the world record of 403.32 kilometers (250.611 miles), which Patrycja Bereznowska of Poland previously set at Poland’s UltraPark Weekend 48 Hour race on May 15, 2022.

Jo Zakrzewski - 2023 Taipei Ultramarathon - 48 hour world record - smile

Jo Zakrzewski having a little fun during her successful 48-hour world record attempt at the 2023 Taipei Ultramarathon. Photo: Ming-Te Lin

While Bereznowska, who finished second to Zakrzewski at this week’s Taipei Ultramarathon, had run a handful of 48-hour events, including an unofficial 401k run in Greece in 2018, Zakrzewski had never raced a 48-hour event and had only run one full 24-hour event prior to setting this 48-hour world record.

That said, Zakrzewski, who is from Scotland but who lives in Australia, has been racing ultramarathons since at least 2010, having run for Team Great Britain at the IAU 50k World Trophy and IAU 10ok World Championships as early as 2011, with three podium finishes at the IAU 100k World Championships over the years. Check out our interview with Jo after her third place at the 2014 IAU 100k World Championships.

Jo Zakrzewski - 2023 Taipei Ultramarathon - 48 hour world record - celebrating

While still en route to a 48-hour world record at the 2023 Taipei Ultramarathon, Jo Zakrzewski celebrates surpassing the British national record for 48 hours. Photo: Ming-Te Lin

Last year, in her one 24-hour race, she bested the U.K. national record by running 247.985 kilometers (154.091 miles).

Full results from this year’s Taipei Ultramarathon 48-hour event are available here.

As with all such records, the official distance and result are unofficial pending ratification by world governing bodies.

Jo Zakrzewski - 2023 Taipei Ultramarathon - 48 hour world record - rain

Jo Zakrzewski weathers rain on her way to setting a 48-hour world record at the 2023 Taipei Ultramarathon. Photo: Ming-Te Lin

Bryon Powell

Bryon Powell is the Founding Editor of iRunFar. He’s been writing about trail running, ultrarunning, and running gear for more than 15 years. Aside from iRunFar, he’s authored the books Relentless Forward Progress: A Guide to Running Ultramarathons and Where the Road Ends: A Guide to Trail Running, been a contributing editor at Trail Runner magazine, written for publications including Outside, Sierra, and Running Times, and coached ultrarunners of all abilities. Based in Silverton, Colorado, Bryon is an avid trail runner and ultrarunner who competes in events from the Hardrock 100 Mile just out his front door to races long and short around the world, that is, when he’s not fly fishing or tending to his garden.