Meb Keflezighi of San Diego outlasted a slew of younger, world-class runners to become the first U.S. man to win the marathon since 1983.

Sources:

[1] Boston Athletic Association, Science of Sport. Bonnie Berkowitz and Richard Johnson/The Washington Post. Published on April 21, 2014, 9:54 p.m., http://www.washingtonpost.com/how-meb-won-the-boston-marathon/2014/04/21/2e7d1d9a-c9b1-11e3-a75e-463587891b57_graphic.html.