Watch: The Other Side of Possible

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The Trans Pecos Ultra (TPU) is a 170-mile stage race run through Texas’ Chihuahuan Desert in Big Bend Ranch State Park. With more than 15,000-feet of vertical gain over the course of six stages, it’s no flat desert jaunt. Even in October, the Texan sun is a formidable force.

Participants carry all of their gear, with the exception of water and tents, which are provided at checkpoints and campsites.

At the 2016 event, the 03xx Foundation teamed up with video producer Ryan Paulk and the TPU team to capture the story of a U.S. combat veteran, Thomas Karlick, who has found ultra running as a way to cope with the challenges of reintegrating into civilian life post-war.

A note from the producer: “This content is made available to the public free of charge. If you would like to show your appreciation to the creators of this film please visit the link: following this presentation.”

Want to Know What It Takes to Finish at Western States? Just Ask Hellah Sidibe.

Find out what happened when this six-year run streaker and HOKA Global Athlete Ambassador took on an iconic ultramarathon in California's Sierra Nevada