Legs were fine in the end thankfully, cheers. I was a bit tired during the day, that's par for the course when I'm looking after either of the kids anyway, but nothing I couldn't handle. Did another 10km last night around the Rotherhithe spur, I think it's my new baseline. I'm pretty happy with my progress, considering I only started recently and could only manage 3km or so in twenty minutes when I began.
The main reason I've taken it up is because I don't really have the time to do polo any more. I'm only free in the evenings after 9 pm when both kids are gone down.