Tower Running is exactly what it sounds like: running up staircases in skyscrapers, as fast as possible. While still an underground phenomenon propelled by a few extreme fitness addicts, tower running is a rapidly growing discipline and a nice diversion for those tired of plain old running on the street.While many tower runners compete in marathons and road races too, it's the added intensity of sprinting up thousands of stairs that makes tower running so challenging. Measuring steps, adjusting to altitude, fighting vertigo, and enduring searing physical pain are all part of this urban competitive running experience.