I have had a sore right knee after training for and participating in a 10k run in October.
It's not too sore but feels stiff when I run and sometimes get pain from half way down my shin through the knee to half way up my thigh. If I kneel on the floor for any length of time it feels like there is no power in that knee to get up and is quite stiff.
I am still trying to determine whether cycling is aggravating it or not as I got some new winter road shoes at around the same time which I use for commuting every day. I've only cycled twice this week and it's not too sore, but I also havnt been running gor weeks. I use the floating shimano cleats with sidi road shoes (which are a tad narrow to be honest). I also got professionally fitted for new running shoes (after the 10k) and the guy in the shop did seem to think I did have misaligned hips and perhaps this was causing the problem.
Been meaning to get it checked out but will probably leave it until after Xmas.