Watching world-class sprinters run as fast as they do, your natural suspicion is that they are straining with every muscle, fists in balls pounding at the air, brows furrowed and veins in their neck ready to burst from the the sheer strain of racing at the 20+ miles per hour they do. But that’s not how it is at all. Instead, you see their palms completely open, brows smooth, and most improbably, cheeks bouncing back and forth against the sides of their face, all loosey goosey as the soft pliable flesh they are in their natural state. The picture is…