I'm in that place at present. Caught a cold on the Saturday of the May bank holiday, which was fairly bad. I have been cycling to work since.
Yesterday I thought I'd got over the worst until it was time to ride home.... Zero power!
All day I've had a headache and again, a loss of power.
So I've not done any circuit training or metcon, but just done the 7 mile each way commute daily.
I was hoping to ride at the weekend, but I'm not too sure now.
I am off to Mallorca at the end of the month, and I have a bike for 6 days, I'll cry if I still feel below par!