As I said Thomas, they were demonstrating it, some guy from the institute of Biomechanics in Vancoover. Theres no impact with the heel,you run by the lift of the knee, not by the drive of the floor.Basicaly its the opposite to how you would normaly run, but it works.the only guy I can think off who ran Like that was Jesse Owens. Youre falling forward, there was one guy there who was having previous problems with his calfs,but I dont know if that was previous to him trying it. With me the jurys still out, thinking about it.