Amazing Weariness

I've been sleeping well recently, and especially in the last few days. So how is that my weariness sometimes amazes me? Further evidence, if it were needed, of the depredations of old age. For some reason my left knee has decided not to function adding to my general sense of all not being terribly well. Oh, and I'm sort of sniffling with a semi-sore throat that's been around for over a week now. But apart from that, I'm pretty well, thanks.