It's the cube square law in action. Elephants can seriously injure themselves from falling over. If I fall over I get a sore butt. Yet if you were to scale me t

It's the cube square law in action. Elephants can seriously injure themselves from falling over. If I fall over I get a sore butt. Yet if you were to scale me to the kind of weight an elephant has, I'd have a far larger fall, so obviously scale has a real effect. I think the thing is, NFL running backs are trained to survive that kind of abuse.