Canadian ultrarunner Stephanie Case trained in extreme cold to prepare for the Antarctic Ice Ultra. She spent 20 minutes in a cryotherapy chamber set at -130 C in Geneva, Switzerland. The chamber warmed to -25 C during her session, supervised by an osteopath.

Case aims to become the first woman to complete the 100-mile race in Antarctica. She hopes to challenge the current record of 22:40:47, set by Yusheng Ni. Case has experience in ultrarunning, including winning the 450-km Tor des Glaciers in 2021. Read more trail coverage.

Case founded Free to Run, an organization supporting women and girls in sports. She uses her Antarctic challenge to highlight barriers women face in sports. Donations for Free to Run can be made through her Instagram. Related: Hong Kong Ultra Challenge Film Chronicles Runners' Journey.

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