So, having had to cut short my long run on Saturday due to knee giving up on me, I was uncharacteristically sensible yesterday and DID NO EXERCISE OF ANY KIND for the whole day. I lounged, I read books with my leg up on the sofa, I wallowed in the Archers omnibus, slow roasted pork, set up fremented salsa and resisted all invitations to try the new 26' trampoline that has obliterated what was left of our garden. I even drank wine.
Then I went for a very gentle 5k recovery jog this evening. Hips still grumbling a bit about the increased mileage and DOMS in the quads but the knee gave me not so much as a twinge. In fact the whole run felt almost effortless, as if I was glidng along. I made a conscious effort to keep my speed down, resisting the urge to match other runners pace etc, but somehow was still home sub 30, which I can't quite understand.
So: Hurrah for the restorative powers of the rest day. I am so taken with the idea that I may have another one some day.