JJ Abrams broke his back rescuing Harrison Ford

Apparently Abrams is a real life superhero:
http://uk.complex.com/pop-culture/2015/07/jj-abrams-broke-his-back-for-star-wars-the-force-awakens

Why did they make that door so heavy? The whole set is fake, right? So, it could just have easily been made of Balsa wood. Then it wouldn't have fell off.

I'd also worry about his bone density...

You'd be amazed at what our muscles are capable of doing to ourselves. A climbing friend of mine who climbs at a very high grade had sufficient strength to snap a finger bone just by how hard he was gripping a hold on an overhang. The tendon in his middle finger was pulling so tightly that the bone just snapped. We've all heard of people slipping a disk when lifting a heavy weight, I'd imagine it is not too extraordinary for that slipped disk to become a broken bone. And, of course, he was probably lifting badly. Not sure I'd rate him a hero though as I'm pretty certain he wasn't expecting his actions to threaten his own health in any way.

Do any of you who've seen the film Django Unchained remember the part where Plantation owner smashes the wine glass and cuts his hand? That was not in the script but an accident, de Caprio just kept right on doing the scene while his artery was pumping out life and Quentin Tarantino was smart enough not to yell cut until the line was done. I had always thought de Caprio just a pretty boy until I heard that story, and on watching the scene again later, realized I was seeing a real trouper in action.