In deference to still not being 100% free of a cold, I drove over to the river for a gentle jog.
As I got out of the car there were other other dog walkers just loading their dogs back into theirs. I went to walk past - very carefully avoiding the very icy puddle at the back of one of the cars - and suddenly, and very painfully, found myself flat on my back.
The other dog walkers were very good - they grabbed my girl and put her back in my car for me while I lay on the ground till I felt able to get up, and they made sure I was okay before they left.
I still had to exercise my poor bewildered girl though, so I put on my fleece and gloves and pottered off.
After about 10 minutes I felt a bit bored, and my back was just feeling bruised rather than feeling like I'd done something really awful, so I had a little bit of a jog. Probably not to be recommended, so feel free to lecture me.
Home now, I'm taking an ibuprofen with my lunch and then I'm going to lie down with in ice pack.