It sucked (and made working out generally miserable).

When to an accupuncturist and it cleared up after three visits.

The other problem I've had this year is getting sick on vacations. It sucks because I always gain weight on them and then can't really work out the first week or so I'm home (when I really need to). Then, when I finally can work out again, I get sore because it's been so long.

The filp side of this is that I always seem to be stronger the first couple of workouts after overcoming some kind of infection (can usually pump out a few more reps than normal). I sometimes wonder if theres some sort of physiological basis for this (e.g., my body has some sort of residual energy buildup after fighting off the infection).