I'm writing this from a hotel room in Birmingham, I'm away with my daughter at a "supernatural" convention, the idea is that she'll go and mingle with fellow fans whilst I try and unwind a bit* after the latest restructuring at work.
I brought my trainers but my knee has been so painful it's felt dislocated, difficulty bending it, feels bruised, wasn't sure if I'd be able to drive etc. Anyway, I thought I'd try it out at the hotel gym and it was fine, so then went for a run outside and it was still fine so finished off with a swim / sauna session.
Now I'm back in the hotel room it feels fine, looser, not so swollen..!? So my advice to anyone else with a painful knee is just try it out, you might be surprised**
**Disclaimer, I'm not your Doctor, please don't sue me if this turns out to be bad advice for you.