Hmmm, I requested wake-up call (metaphorically speaking) at 5:30, it is early...
Felt very little vim, and also stiff feet and lower legs (have of course completely failed to do the calf-stretching regimen - I will start back again today, it is very useful). Decided I had better do a really unambitious workout that I could execute properly. Stopped partway through to use the bathroom (this is an attractive feature of doing my run around school playing fields - nice clean bathrooms with toilet paper, sink and soap and paper towels, etc.!), felt better once I had emptied bowels. By the end was convinced I could have done the whole run at zone 2, but certainly had not felt that way till about the 40-minute mark, so I guess I made the right choice!
9 x 3min high Z2, 2min walk