One of my buddies in Engineering is a free runner. Dude has some SERIOUS forearm muscles and calves. He's never broken a bone, but has torn LOTS of ligaments/tendons/etc....
Watching that reminds me of the scene in the movie Kickass where the hero takes off running across the rooftop and right before he gets to the edge he skids to a halt and looks over the edge. Screw that.
They actually have a world championship of Parkour every year, it was really good the one for this year with lots of stunts that involved jumping from one roof building to another one, and they have this spots mark with an X that they have to touch to make the points for the stage.