See what it's like to push your body to extremes in a live Web chat with ultra-runner Marshall Ulrich on Monday, May 16, at 11 a.m. PT (1 p.m. CT, 2 p.m. ET).
Ulrich, author of "Running on Empty: An Ultramarathoner's Story of Love, Loss, and a Record-Setting Run Across America," has taken ultra-running to new extremes.
He's finished more than 120 ultra-marathons, crossed Death Valley 21 times, won the Badwater race four times, and competed in nine Eco-Challenges.
Can't make the chat? Email your questions in advance to chat moderator Roy Wallack at firstname.lastname@example.org.
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Photo: Ulrich on a run, pictured right. Credit: Richard Hartog / Los Angeles Times