I was 27 years old, I bent over to put a barrett in my DD's hair and threw my back out LOL
My doc said he sees very simple movements cause this all of the time, more often than actual injuries/falls.
You move just slightly wrong, at a slightly wrong angle, holding your mouth slightly off.... :roll: and out it can go.
Strengthening your abs and back muscles is important and does help, but sometimes it just happens :D:D:D