While it seems counter-intuitive, most people actually burn about the same amount of calories walking a mile or a kilometer as they do running the same distance. Of course, this can vary with a person's weight and the intensity in which a person conducts the activity, but for most people, the caloric burn is the same. So, if you want to save time, run; and if you want to spare your joints, walk; but if you want to burn more calories, go farther.
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