Cold, Flu, & Cough Health Center

Exercise and the Flu

Can exercise keep you from getting the flu this year? What if you're already sick with flu symptoms? Should you push yourself to work out anyway?

No one can deny the benefit of a regular exercise regimen on overall health and disease prevention. Findings continue to support the benefit of regular exercise in strengthening the immune system, enabling it to fight viral and bacterial infections.

Yet what if you have fever or other flu symptoms? Should you continue to exercise? Would even a light workout worsen flu symptoms? Let's find out.

Can Regular Exercise Help Prevent the Flu?

Maybe. The most effective way to stay well is to keep your immune system strong. Taking care of yourself by eating nutritious foods, exercising regularly, getting ample sleep, and avoiding and reducing stress can go a long way toward helping you prevent chronic illness.

According to recent findings, when moderate exercise is repeated on a near daily basis, there is a cumulative immune-enhancing effect, which leads to a sustained response by the immune system to illness. When you exercise, your white blood cells -- the blood cells that fight infections in the body -- travel through your body more quickly, fighting bacteria and viruses (such as flu) more efficiently. To maintain good health, experts recommend at least 30 minutes of aerobic activity such as walking, swimming, biking, or running each day.

While regular exercise helps keep you trim and fit, there are also two other benefits -- reduced stress and better sleep. Stress can wreak havoc with your mental and physical health. Regular exercise helps reduce stress hormones such as cortisol and adrenaline that can tear down immunity. In addition, getting seven to eight hours sleep each night is equally important for staying well and helping your immune system fight viral and bacterial invaders. Exercising daily helps to improve healing sleep.

On the other hand, extremely vigorous forms of exercise, including working out for hours at the gym and running marathons, can have a negative effect on your immune system. Studies show that extreme workouts can decrease the number of white blood cells flowing throughout your body while increasing the level of stress hormones in the bloodstream. These emergency hormones help you cope with the physical stress but can also increase your likelihood of illness.

Can Exercise Aggravate my Flu Symptoms?

While mild exercise can help boost your immune system, you may want to be gentle on yourself if you already have the flu. That's when it's time to listen to your body, and give it time to recover.

The bottom line? Rest your body when you have the flu. Allow your body a chance to adjust to the stress of illness. Your immune system functions best when it is not stressed or in overdrive.