I injured myself last Friday. Nothing of the usual home injuries. Didn't take a fall, step on a pin, hit my thumb with a hammer, pick up the business end of a soldering iron, or bang my head on an open cupboard door. No, I executed a sudden maneuver. I was outdoors, testing a type of lightweight fabric used for roofing, when my sample started blowing away from me. I lunged for it after chasing it across the roof a few feet, to catch it. Something happened in my ribcage and knocked the wind out of me temporarily.