The day after and I didn’t feel too bad as I went out for a 5km run on the nice flat grass of Netham Park. It was a gentle trundle and the only excitement was when a large wolfhound tried to take a chunk out of my hip (I’m sure it was the same one who tried to take a lump out of my arse previously). I’d done some stretches before and whilst there was some achiness in the muscles, there was no pain. I seized up a little sitting around after I got back, but I think regular gentle movement and stretching might be the key here.
I have also now switched back to metric measurements for my watch and the Garmin website (though I still need to reset my lap marker on my watch).