Ran again yesterday for the first time since Tuesday, and I feel OK. Luckily we got going before it got too hot, and did a nice steady 15km or so in about 90 minutes. I'd spent rather longer, and drunk rather more, than I had intended to at a party on Saturday night, so I think I may be on the road to recovery. Today is most definitely a day off, as opposed to an off day, and I may even run again tomorrow. Woo.
The only problem now is the weather. Look away if you are in the northern hemisphere. It was well into the 30s yesterday, at least 30 today, and much the same forecast for the rest of this week. I may have to get up early to run when it's reasonably cool. I'm going to have to put ice down my shorts to acclimatise me for London.