https://www.youtube.com/watch?v=l2B0-Mi37PE Alright, so I watched the above video the other day and it showed GSP being able to punch with 2859 (or something) pounds of force, and kick with 3477 pounds of force, which I found ridiculous. Right, so, here's where the physics comes in. 3,477 lbs force is 15,466 in newtons. I'd say it takes anywhere between 2500 - 4000 (between 560 & 900 lbs force) newtons force to break a rib. In a car accident at 30mph, without a seatbelt, most people would slam into the dashboard with less than 3,477 pounds of force. Let's say this guy can kick that hard and that Sport Science is right. Surely this means that a properly executed kick in the midsection from GSP would break a rib, and since the force he can apply with his 15,466N kick is about 4 - 6.5x the amount required to break a rib, wouldn't this also cause much, much more damage than that? Also I saw Cain Velasquez on sport science and his punch (according to them) lands less force than GSP's does, and Velasquez is a heavyweight.