Dean Karnazes is the author of the bestsellers Ultramarathon Man, Run! and 50/50. TIME Magazine called him one of the 'Top 100 Most Influential People in the World,' and he has been featured in Runner's World, TIME, Newsweek, People, GQ, The New York Times, USA TODAY, The Washington Post, Forbes, and many others. He's travelled the TV and radio circuits as well, logging miles on The Today Show, 60 Minutes, The Late Show with David Letterman, CNN, ESPN, NPR's Morning Edition, and the BBC, among others. He lives in California.