Any running shop can outfit you with warm winter running tights, a cool stopwatch, or the best summer dry-fit shirt. But only the best can motivate you to actually get out and use the stuff you spent all that money on. Founded in 1975 and one of the first running specialty stores in the country, Marathon Sports provides as much inspiration as gear. The knowledgeable and eager salespeople invite you to test out your sneakers with a jog on the sidewalk before you buy, and the stores organize regular training runs and an annual 5-mile road race in Wellesley. Cheaper prices can be found, but with such expert guidance, Marathon Sports runs circles around the competition.