Why extreme fitness is booming: 'I got kind of addicted'

Tech Insider : Economy, Business
Illustration of people running.

Dan Page for BI

This ultrarunner was diagnosed with cancer 2 years ago, but didn't let it stop him. This summer, he'll run over 100 miles through Death Valley.

Tech Insider
A side-by-side composite image: on the left, a close-up of runner's shoes on a desert road; on the right, a photo of ultrarunner Ray Zahab
Ray Zahab is the perfect example of an endurance athlete.

Getty Images; Photo courtesy of Jon Golden; BI

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