In his latest trail running video documentary, runner and producer Billy Yang tries to find an answer to the intriguing question of why anyone would want to run 100 miles.

An accomplished filmmaker and trail runner, Yang sets the video around the 2017 Leadville 100 in Colorado—a race that he is running. “I think it’s in our nature to be curious creatures, and certainly the determined among the bunch will constantly seek the next thing,” Yang says in his opening narration. “And for me personally, I wanted my next challenge to be the Leadville 100.” Watch “The Why: Running 100 Miles” and see how Yang answers the question in this compelling film.

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