The idea of working out while sick has been on my mind a lot lately. After a knee injury that left me nervous to exercise, I slowly dragged myself to the gym again starting this January. But every time I feel like I'm starting to get into a workout groove, I start to feel exhausted—like I'm getting one of the pesky sinus infections that slow me down and cause me to take a day or two off.
I always wonder—would exercising actually help me get better, or am I doing the right thing by self-prescribing a few gym days (or nights) off? (I mean, we often hear that exercise helps to keep immune issues at bay, so it could treat them, too.) But before I go on and on about my hunches, it's probably best to hear it straight from the experts. So go on—keep reading to find out whether working out while sick is beneficial.
Exercise as a preventative health measure
If you're currently healthy and want to stay healthy, exercise is key. Studies have shown that moderate aerobic exercise—aka things like 45 minutes of biking, running, or even walking—can cut your chances of getting a respiratory infection and other wintertime illnesses by more than half. And why is this? One study's lead researcher, David Nieman, MD, explained that exercising increases your immune system cells that fight off foreign pathogens. Although it takes only a few hours for that level of immune cells to decrease, it still gives you the boost you need to fight off things like a cold.
When it's okay to work out
Something called the "above the neck rule" can usually answer this question. "If your symptoms are neck up—things like sinus and nasal congestion, sore throat, etc.—exercise neither helps nor hurts," says Nieman. So if it makes you feel better to get a workout in, go for it (just don't expect it to cure you).
Fitness expert and strength and conditioning specialist Jennifer Bayliss says you can stick to your normal exercise routine if you'd like. If you want to get a workout in but can't find enough strength to do what you'd normally do, consider doing a little yoga or head out for a walk instead of a run.
"Decreasing the intensity of your workouts makes breathing during the workout easier and is less taxing on your immune system," says Bayliss. "If you find that the physical exertion makes you feel worse rather than better, stop and rest until you're well again."
Sidenote: If you do choose to go to the gym, be mindful of using sanitizing wipes on the equipment to try to make sure you do not get others sick (yes, consideration is key).
When you should take a break
Ailments like fever, muscle aches, vomiting, wheezing, and diarrhea are signs that you need to sit out this workout (and maybe the next few, for that matter). A fever over 101º should always tip you off to stay home because it can lead to dehydration. "The danger is exercising and raising your body temperature internally if you already have a fever," says Lewis G. Maharam, MD, a sports medicine expert.
And Wayne Stokes, MD, director of sports medicine at NYU Langone Medical Center's Rusk Rehabilitation, agrees. Stokes says that exercising with a fever can cause myocarditis, an inflammation of the heart muscle that can lead to heart dysfunction, failure, and sometimes, death. "It's not common, but it is possible (and good reason not to push yourself)," says Stokes.
So the next time you're feeling out of sorts and aren't sure about working out while sick, put the above-the-neck rule to good use.