Huh, well it's good that you didn't like break yourself. That'd be bad. :c
I can vouch for the fact that falling flat on ones back hurts less than one would believe, it actually hurts much more to land on your bottom. Well, unless you also bang the back of your head against the floor, but i fortunately avoided that when i made a Goofy-style slip and fall on ice. I mean really, i slid a few meters on one foot, obviously with no balance whatsoever. Then my foot slid away under me, and i crashed down on my back hard enough to make the ice crack a little. And this was ice that could take the weight of me, my bro and my dad all at once, which at the time was probably around 230 kg of mass in total. And i was the lightest of us. It didn't really hurt, possibly because the short uncontrollable slide prior to the meteoric crash got me full of adrenaline. :U
@jisse: Now if only people would actually pay for it, then it'd be a nice step towards me making a living off of being a silly dude on the internet!!