Nike followed up that blast with its own hard data. Jeff Pisciotta, the senior researcher at Nike Sports Research Lab, assembled twenty runners on a grassy field and filmed them running barefoot. When he zoomed in, he was startled by what he found: instead of each foot clomping down as it would in a shoe, it behaved like an animal with a mind of its own—stretching, grasping, seeking the ground with splayed toes, gliding in for a landing like a lake-bound swan.
