Dave McGillivray is an improbable advocate of virtual exercise. The race director of the Boston Marathon for 30 years, McGillivray estimates he's logged more than 150,000 miles in his lifetime, the overwhelming majority of them outside, and a formidable number of those in Forrest-Gumpian feats of endurance. In 1978, he ran from Medford, Oregon to Medford, Massachusetts—a distance of 3,452 miles—for charity. In 2004, he did it again.

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