Stephanie M. Lee, San Francisco Chronicle

As Natalie Mar staggered up the steep switchbacks last weekend near Lake Tahoe, she wasn’t certain she’d make it.
She had just scaled a 12-foot wall, dived into a bath of icy water and slithered through mud while ducking barbed wires that dangled 8 inches overhead. And now she was running an 11-mile trail with a 1,500-foot elevation change.
“I’m going to die,” Mar, 24, thought.
But she didn’t, and she cleared the switchbacks. Her reward: to belly-crawl under live wires.
It’s all part of the fun at Tough Mudder, a daylong, boot-camp-style event that puts athletes to the test with long distances, daunting obstacles and an emphasis on teamwork. A waiver in the case of death is required to enter.

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