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With mile after mile of joint-jarring impact, of battered quads and blackened toenails, marathon training is daunting under the best of circumstances.
This winter, an especially cruel combination of bracing gusts and numbing cold courtesy of the dreaded polar vortex, has tested the resolve of the most disciplined runners, particularly the thousands training for their first Boston Marathon.
A year after two bombs killed three spectators and injured more than 260 near the Marathon finish line, the race will return in tribute and defiance, promising a deeply emotional experience many runners say they are determined not to miss. Even as yet another winter storm barrels in, battling the elements is a small price to pay, they say.