About ten years ago, when I still had a home office to go to, after a leg day at the gym, I was climbing up the stairs, to said office, with a cup of tea in one hand and a couple of biscuits on a plate in the other. One leg buckled as I was on about the third riser. As I fell back I had two thoughts, "save the tea and cookies" and don't hit the sharp square edge of the laminated (big)TV stand with my back. So I bent forward to avoid the stand and keep the plate level .

Hit the floor an almighty thump, on my backside with my torso essentially vertical, think touching your toes position, only arse first. Saved the cookies and most of the tea.

Long story short. Subsequent Xray and MRI showed I severed the disc L4/L5 and a crescent moon shaped piece of disc is now floating about in there poking at various things as the mood takes it. Medical opinion is "live with it" there's no pain. Left leg has a slight muscle quiver, and the knee has grown some funny bumps. It takes a lot of work to match strength of the right leg. My run makes Lionel look elegant, I don't kick when I swim (never did anyway) and I fall over a lot in transition.

I may have done dumber things since then.....but I never try and save the cookies anymore.