i've heard that if your cold is above your neck then you should be fine, but if its on your chest then you can strain your heart or something if you over do your exercise. I dont know if thats true, but i think that recovery is important so i would probably skip the exercise and let my body work its way through it (with lots of nice cold and flu drugs
). Plus if you're going to work out in a gym you're probably going to spread it around which people wont appreciate
but i think you work out at home mostly right?