We regularly hear comments from runners or athletes saying they are forced to suspend their training since they are colds. In reality are they wrong? According to a recent study, a workout from medium to cardio intensity causes no significant difference in increasing the cold symptoms or upper respiratory infection. In the presence of mild symptoms (runny nose, mild sore throat ...) you can continue to train. It would be wise to reduce the duration and especially the intensity of your workouts, especially early in infection, when you do not know if your condition will get worse. If the symptoms are severe (cough, congested lungs, difficulty breathing, body aches, muscle heaviness) quit without hesitation intensive training for at least four days and expect to be fully recovered before resuming. A break of a few days will have no effect on your fitness while conversely, a too much early come back in training may delay your recovery and even cause complications. If fatigue is still present after the symptoms have faded, just keep only half of your normal training volume during the first week of recovery and avoid any violent effort that would seek a large lung work. Also avoid training session with friends who would likely set you into challenges you could not resist. Everything should be back to normal after a few days!