This article is a guest post written for the 100 day marathon plan blog by Duncan Larkin, 2:34 marathon runner and writer. Enjoy ! At 13.1 miles or 21.097 kilometers, the half-marathon is a race distance that most aspiring marathoners tackle first. The pros benefit from half marathons as well—using that race to “tune up” a month or so before their peak marathon in the spring or the fall. If … [Read more...]