Should I Still Work Out if I’m Sick?

Updated: Jun. 30, 2022

Exercise is great for your health...until it isn't.

01_Sick_should_I_still_workout_if_sick_istock/digitalhallway

If you have a regular exercise routine, you might feel guilty skipping your workout when you’re sick. But even if you felt well enough to go to work, taking a rest day could be the best thing for your health.

Listen to your body when you’re deciding if a workout is worth it, says Albert Ahn, MD, clinical instructor in the Department of Medicine at  NYU Langone Medical Center in New York. If you’ve got a minor cold and your symptoms are from the neck up, you can probably handle light exercise. Some people even find they feel better with physical activity. Though the reason isn’t clear, it could have to do with the endorphin rush or sticking with a routine, he says.

The exception to the neck-up rule? If a cough or stuffy nose makes it hard to breathe, says Felicia D. Stoler, DCN, RDN, a doctor of clinical nutrition, registered dietitian nutritionist, and exercise physiologist in Red Bank, New Jersey. “We need oxygen to exercise properly,” she says. “If oxygen is a little challenging because the lungs are filled up with fluid, maybe you shouldn’t work out.” (Find out why you’re always congested.)

Take it easy, too, if you’ve had stomach issues like nausea, vomiting, and diarrhea, even you think you’re done running to the toilet. “They’re already dehydrating to begin with, and the last thing you want to do is make that worse,” says Dr. Ahn. In addition to water, you also lose electrolytes—which are important for performance—so replenish them with sports drinks or coconut water. (Check out these other sneaky causes of dehydration.) Plus, if being sick made you lose your appetite, you won’t have enough calories to fuel your workout, he says.

Exercising with a fever is another big no-no. “You don’t want to raise your body temperature any more,” says Dr. Ahn. (Here are 12 Times You Should Absolutely Skip Your Workout.)

Then, of course, there are the germs. For one thing, you should avoid making other gym-goers sick. But staying home could protect you, as well. “You don’t want to be around other people’s germs when immunocompromised,” says Dr. Stoler. If you do brave the gym, she recommends washing your hands when you arrive and when you leave. Avoid putting your hands in your eyes and nose until you’ve washed the germs away.

Don’t rely on getting an immune system boost from your workout either. Research, including a review of studies published in 2019 in Journal of Sport and Health Science, show the positive effect of exercise on the immune system, but that won’t make a difference once you’re sick. After all, your regular exercise routine has likely already given you those benefits, says Dr. Ahn. Now it’s time to let your body fight the infection and avoid these habits that ruin your immune system.

Fitness fanatics who do decide to work out should dial it down a notch. Reduce the speed and number of miles on the treadmill, and do fewer sets and reps during weight training, says Dr. Ahn. Or rethink your idea of physical activity and do tai chi, yoga, or light cardio, suggests Dr. Stoler. “It’s moving vs. sitting on a sofa,” she says. “We can always walk.”

Don’t feel guilty about the time away from the gym. A few days off won’t kill your progress, and working out too soon will probably just hold you back more in the long run. “It’s not going to help your cold go away any faster,” says Dr. Ahn. So sit back and enjoy the excuse to stay in your PJs.