Nothing throws a wrench in your workout routine quite like getting sick. Depending on your specific symptoms, you might conclude that exercise won’t happen for a while. Sometimes, however, you may feel well enough to get moving. Getting some fresh air and a little movement might even seem like a good idea—but it’s not always easy to tell if doing so would help or hurt the situation.

So should you work out when sick, or should you prioritize rest? We spoke with experts to get to the bottom of it.

Should You Exercise When You’re Sick?

While it’s not the easiest question to answer, experts agree that whether or not you should work out when sick really comes down to your specific symptoms. For instance, dealing with a mild cough requires a different recovery compared to experiencing the flu, COVID-19, or other contagious diseases.

“While exercise has numerous health benefits, it's essential to listen to your body,” says Shoshana Ungerleider, MD, a board-certified internal medicine physician at Crossover Health in San Francisco. “If you're feeling slightly under the weather but overall OK, light to moderate exercise might be permissible. However, if you're feeling genuinely unwell, it’s often best to give your body the rest it needs.”

So, how do you know whether your specific illness warrants a rest day or permits a quick workout? To answer that, we’ll first need to dig into when not to exercise when you’re sick. 

When Should You Avoid Working Out If You’re Sick?

As you’re staring at your workout clothes, you may wonder when it’s the wrong time to break a sweat. In some cases, your symptoms can serve as your body sending you “warning signs,” explains Sean Rockett, MD, a board-certified orthopedic surgeon and senior partner of Orthopedics New England in Natick, Massachusetts. 

Here are some symptoms that call for skipping your workout when sick:

These are only a handful of the symptoms that signal you should avoid your regular exercise routine. If you’re experiencing any other symptoms that are tied to contagious diseases, you should also stay home and recover until you feel better. And remember, it’s smart to check in with your doctor if you're not sure whether or not you should work out when sick.

When Is It Safe to Work Out If You’re Sick?

It’s appropriate to exercise if you’ve just been dealing with a mild cold, “especially those with symptoms limited to above the neck, like a runny nose or sneezing,” Dr. Ungerleider says. “If you’re experiencing these milder symptoms and still feel like working out, you can, but you should reduce the intensity and duration of your exercise.”

Dr. Rockett agrees, noting that before you dive back into exercise, you should also simply start feeling like yourself again. By listening to your body, you can better determine if it’s safe or not to exercise when you’re sick. “Start off at maybe 25 percent of your normal duration or intensity, and then work your way back up,” he recommends, explaining how you can incrementally increase your exercise duration or intensity to 50 percent, 75 percent, and so on over the next few days.

All that said, if you had (or still have) a fever, experts say you aren’t cleared for a workout quite yet. You should wait a few days after your fever has broken before resuming exercise, according to NYU Langone Health. 

Is Exercise Good for a Cold?

Depending on your symptoms, exercising while sick could even aid in your recovery. For instance, Dr. Rockett notes that if you’re experiencing minor head congestion, working out may provide relief, as it can help open up nasal passages.

That said, every situation is unique. And remember, if you have a fever or experience any of the “below the neck” symptoms mentioned earlier, it’s important to give your body the rest it needs.

Tips for Exercising While Sick

Your workout clothes are on and you’re finally feeling ready to get active again. There’s excitement in this moment, but it’s also understandable to have some trepidation about jumping back into exercise after feeling under the weather. 

These conflicting emotions are exactly why it’s smart to start at a lower intensity and/or duration, as Dr. Ungerleider and Dr. Rockett both recommend. Here are a few other pro tips to keep in mind as you’re getting back into your regular workout routine: 

1. Avoid Working Out In Public or Taking Group Classes

It might be tempting to go to your local gym or favorite group exercise class, but for the safety of others exercising near you, it’s best to avoid these spaces until you’ve fully recovered. If you decide to do a solo workout outside instead, just make sure you have the appropriate clothing (i.e. wear extra layers if it’s cold out).

2. Start with a Low-Intensity Workout

Beyond lowering your specific workout intensity level, you can also choose an exercise that doesn’t push you too hard. “Consider walking instead of running, or doing a gentle yoga session rather than a high-intensity class,” Dr. Ungerleider says. (Psst: You can enjoy all of those activities on the Peloton App!)

There’s also good news for those with a Bike: “A stationary bike and Peloton work is great because you’re seated and not having to do a lot of jumping or twisting or turning,” adds Dr. Rockett. 

3. Stay Hydrated

Water is your BFF with this first workout back. Your body likely needs extra fluids, so take as many breaks as you need to hydrate.

That said, don’t overdo it: If you start your workout and have “a severe headache or nausea or feeling like you're vomiting—I wouldn’t push yourself that hard,” Dr. Rockett says. Speaking of which...

4. Listen to Your Body

At the end of the day, your body will let you know if it’s not time to hop back into exercising. “If you start feeling worse, stop immediately,” Dr. Ungerleider advises. 

By factoring in all of these considerations, you should be both prepared and motivated to return to your regularly scheduled programming. 

When to Return to Your Regular Workout Routine

We’ve discussed how starting at 25 percent of your typical exercise intensity or duration is best as you’re coming back from sickness, but when can you return to 100 percent? It’s pretty simple: It’ll be clear that you’re ready for 100 percent when you’re feeling 100 percent. 

Again, it also goes back to what illness you’re working through. “When your symptoms have significantly improved or resolved, and you feel close to your normal energy levels, you can consider returning to your regular exercise routine,” Dr. Ungerleider says. “However, it's essential to ease back in. Gradually ramp up your intensity and duration over several days to ensure you don't overtax your body.”

This rule generally applies to those who’ve experienced a mild cold or illness, and it should only take a few days before you’re back to feeling and performing close to or at 100 percent. But if you’re recovering from something a bit more severe, you’ll want to consult a healthcare practitioner first, especially if you were feverish or experienced vomiting or diarrhea. Having the go-ahead from your doctor will also make you more confident about adding your favorite workouts back on the calendar. 

The Takeaway

Getting sick isn’t fun or easy for anyone. You may need to take time off work, skip out on activities with loved ones, and of course, avoid exercising. While working out can sometimes make you feel better in your recovery, it could also worsen your current symptoms, which makes it a bit tricky to decide whether or not you should work out when sick. Evaluate your symptoms and slowly ease back in to your fitness routine once it’s appropriate using the tips above. If you have any other concerns or more severe symptoms, prioritize rest and reach out to your doctor. And remember: walk, don’t run, on your road to recovery. You certainly won’t regret being gentle with yourself as you ease back into your workout routine.