Heal quickly and bravely, Avocet!

Snappy retorts - the best I can do "you wouldn't be telling me to stop driving if I'd had a car accident, would you?"

That doesn't work for mt biking, of course, but for commuting it does annoy me that people feel biking is somehow wild and reckless while calmly accepting driving as just an unavoidable risk - while car driving actually puts other people at risk to a much higher degree.

Or sometimes I say "hey, with all the hours I put in on my bike I have to hit the deck every now and then. If I were a runner I'd manage to sprain something at least once a year, that's just life."

But that's just to the rude+righteous ones. Mostly people do say it as a way of expressing care, and all you can do is smile.