Runners are a dedicated bunch: they'll run in the pouring rain, when it’s below freezing and when it’s blazing hot. They often feel that they need to run even when they're injured or feeling under the weather. They don’t want to miss a single run and think that they need to be tough and “train through” the discomfort. More often than not, though, training when you’re not feeling well is counter-productive.
Chest Cold Symptoms
What most people refer to as a “chest cold” is a condition called acute bronchitis. Bronchitis is a condition in which the air tubes -- the bronchi -- in the lungs become inflamed. The inflamed tissue swells up in the bronchi and narrows the airway; the bronchi also produce mucus. The inflammation and mucus production makes your chest feel “tight,” and it may feel harder to breathe. The inflamed tissue and mucus in the bronchi also make you cough. Other symptoms of a chest cold are a low-grade fever, fatigue, headaches and body aches. Almost all cases of bronchitis are caused by a virus and will go away on their own after a couple of weeks.
The "Neck Check"
A rule of thumb to use when considering a run when you’re feeling under the weather is the “neck check.” If the symptoms you are experiencing are above your neck -- for example, a runny or stuffy nose or a sore throat -- you can proceed with caution. If the symptoms you are experiencing are below your neck, such as coughing, congestion, fever, body aches or fatigue, you need to take the day off. Because the symptoms of a chest cold are below the neck, don’t run until the symptoms go away.
A 2000 study in the journal “Immunology and Cell Biology” discusses the possible complications of running when sick Running with a chest cold will make the symptoms worse and may lead to more severe complications, such as pneumonia. Infection and fever can also affect muscles and nerves, which may lead to less strength and coordination and therefore increase the risk of injury. If you have a fever, exercise will make the fever higher, and you run the risk of developing heat stroke. When you have a fever, your heart is working hard, pumping blood to the skin to try to keep you cool. When you raise your body temperature even more by exercising, the heart may become damaged from having to work too hard. Occasionally, viruses that cause respiratory symptoms can also cause the heart muscle to become inflamed, a condition called myocarditis. Exercise and myocarditis can be a life-threatening complication.
Ready to Run Again
The recommendation from Dr. Goran Friman, the author of the study in “Immunology and Cell Biology,” is to take time off from running until the symptoms of a chest cold subside. When you’re feeling better and ready to run again, take it slow: Go for an easy run instead of your planned track workout. Listen to your body. If you feel worse after you start running, stop and get more rest.
The good news is that research, including a 1990 study published in “The International Journal of Sports Medicine,” has shown that if you engage in moderate exercise, like running, you are likely to have fewer colds during the season, as well as less severe symptoms. However, if you are the unlucky runner who develops a chest cold, you need to be cautious. When you have a chest cold, you need to work on getting better -- not on working out.