To run or not to run, when fighting some kind of cold or sickness, that seems to be the question. My very unscientific thought on this is that if the sickness leaves you feeling as wiped out as if you'd just finished a long run, no matter what the schedule calls for, it's better to give the body a rest. That said, might there be be some value in a short run that has you get your heart rate up a bit, enough to break a sweat but not enough to add to your fatigue? Perhaps getting the metabolism going enough to help move the cold along? That is the route I follow but again, it’s not based in science, just my gut feeling. Then again, if you feel like you’re in a hole, I would think digging the hole deeper will make it harder to crawl out.
Run as smart as you can,
Randy Step, an admitted obsessed runner who obsesses over this kind of dilemma.