'Bonking' is the term used by runners and cyclists to describe the feeling you get when you run out of energy and 'hit a wall'. That happened to me today on my long run. Ran to Bingley 5 rise locks, 15 m into a strong headwind, and 10m back to Guisely with Hugh from Otley AC. Bit of a disastrous run.
The positives: Completed my targeted run; I realise that I can't run a long way without breakfast (sounds obvious, but it means eating 2 hours before a run); Found a nice new route; muscles not that sore despite the lack of energy.
The Negatives: Didn't deal well with running straight into wind for 15m; did not feel as psychologically strong as I have previously; did not really enjoy the run.
Overall, I'm not too disappointed as the weather played a big part, but I do need to be prepared for bad weather on the 'big day'.