Is It a Cold, or Is It Flu? When Are You Too Sick to Work Out?

Should you tuck yourself into bed with a book and a cup of tea when you're sick, rather than head out to the gym? Most people think the answer is obvious — but it may not be.

Are You Sniffling or Sneezing? Working Out May Help You Get Over an Infection Faster

Every winter millions of people who are serious about their health use sniffles, sneezes, coughs, and fever as an excuse to skip their workouts. But a study published by the American College of Sports Medicine reports that moderate exercise may help you get over an upper respiratory infection faster.

 

People who exercise regularly tend to catch fewer colds and to have fewer bouts of flu, although it's certainly a good idea to wash your hands carefully and often when you share a gym with others. Most of the time when you catch the flu, it's because you have breathed in air in which an infected person has recently coughed or sneezed. Touching infected mucus with your hands and then touching your mouth, nose, eyes, or face is the other main way of catching the flu. In the post-COVID age, we're all familiar with all of this, and we're more careful to avoid potential contaminants than ever before.

Even when the virus has entered your body, you won't necessarily get sick. There is a certain minimum number of viruses that have to be absorbed into the lining of your nose or throat to cause infection. How many viruses you need to come down with a cold or flu depends on the strength of your immune system. Smoking weakens your immune system. A single, large dose of vitamin C at the first sign of symptoms activates your immune system. And the effects of exercise depend on when you contract the virus.

• If you do regular, moderate intensity exercise, your exercise habit helps your immune system fight off a cold when you are at rest.
• If you have just done extremely hard exercise or competed in a sports event, then for several hours while you are recovering you are more susceptible to catching colds or flu.

That second characteristic of exercise explains why it is especially important to avoid picking up a cold in a locker room or gym. It is also the reason many professional athletes use herbal adaptogens, such as  eleuthero (once known as Siberian ginseng) or rhodiola, to keep their immune system primed to fight infection all the time. But what if you are already sick?