Canadian Stephanie Case is the first woman to run 100mi in Antarctica

Canadian ultrarunner Stephanie Case became the first woman to complete a 100-mile race in Antarctica, finishing the Antarctic Ice Ultra in Queen Maud Land in 17 hours, 31 minutes and 39 seconds. The 44-year-old ran 160.9 kilometres on a 4.2-kilometre circuit, repeating the loop 38 times and adding a final 300 metres. The race began at 1 a.m. because storms were approaching, and the extreme cold created immediate difficulties: Case had to stop during her first round when ice on her balaclava made it hard to breathe. She later settled into a routine of running ten loops at a time, then warming up in the aid tent. She placed second among 28 runners; China’s Yusheng Ni won in 17:02:24.

A former United Nations human rights lawyer born in Kingston, Ontario, Case has also drawn attention for competing as a mother. In 2025, she won a 100-kilometre race in Wales while breastfeeding her six-month-old daughter, Pepper, prompting criticism from some who argued she should be at home. Case rejects the idea that motherhood should mean giving up personal ambitions, saying pursuing what makes mothers happy can make them better parents. She hopes her Antarctic achievement reinforces that message. After returning to her home in Chamonix, France, she plans to prepare for the 472-kilometre Arctic Spine in northern Sweden, a self-supported winter race involving skis, a sled, snow-melting and tent-camping.