Last night was tough... It was the last Wednesday of the month, which means sparring. We did points, and we did continuous, and my arms were like lead weights by the end of it. "I know I'm unfit, but this is bollox," I thought.
However, I think I've identified (part of), the problem. Yes, I'm unfit, but I think the last time I had a cold (3/4 weeks ago), it went down to my lungs, and I've got an infection (I'm coughing up phlegm that's a vivid shade of yellow, anyway!). When I was running regularly, I noticed that an infection would have a similar effect (ie, I became fatigued very quickly and seemingly massive effort yielded very little in the way of performance), so it's off to the quack, on Tuesday, to get some anti-biotics.
As a follow-up, I'm going to start doing some sprint work, in order to beef up my hams, quads, pecs, biceps and triceps. Ten or twelve 200m reps, twice a week, ought to do it. It'll also improve my stamina - I'm quite pleased with my recovery time, but I run out of gas very quickly, and that isn't just a matter of the infection, I think.