I get asked this question a fair bit…heres a simple guide
As long as you only have mild symptoms above the neck (runny nose, nasal congestion or sore throat), there’s no need for these to be your excuse from meeting up with your friends at the gym.
You should probably swap your training for some R&R if your symptoms are below the neck (chest congestion, cough, stomach problems such as vomiting or diarrhoea) or you have a fever, muscle aches or widespread fatigue.
Athletes and heavy trainers who regularly perform either very intense and/or long-duration exercise are two- to six-times more likely to get sore throats and flu-like symptoms than the rest of us “normal” folks. So think about how hard you are training if you start to feel a bug coming at you…chill out and go do some low intensity cardio, weight, yoga, or pilates.
check out the full article here