When you’re committed to an exercise routine, it’s hard to know what to do if you find yourself with the sniffles. Should you push through and go running with a cold or take some time off to rest and recover?

We get it: Sometimes, a mild cold can feel more like an inconvenience than an illness. But it isn’t always the best idea to run while sick. So we asked doctors how to decide if you can lace up your sneakers or stay put on the couch until you’re feeling better.

Is It OK to Run with a Cold?

It can be, “as long as you are smart about it,” says Elizabeth Gardner, MD, an associate professor of orthopaedic surgery at Yale University School of Medicine and head team physician at Yale Athletics. 

Being “smart about it” involves checking in with your symptoms and being honest about how you really feel—and we’re not talking about feeling like you want to stay on track with your training plan. 

Whether or not you should run with a cold “depends on your symptoms and your energy level,” says Allie Buttarazzi, MD, a double board-certified physician in internal medicine and lifestyle medicine. If you have a mild cold with a runny nose, light cough, and a sore throat, a light- to moderate-intensity run will probably be pretty safe, she says. But if your symptoms are worse or all over your body—think: fever, body aches—or if your energy is seriously lacking, “it’s probably better to rest,” she says.

“Even if you just have a stuffy nose, but it is really hard to breathe, you might want to put off working out until you have some relief,” Dr. Gardner adds.

How Can You Tell If You’re Well Enough to Run?

Depending on your circumstances, the pressure to run through a cold might feel massive. For example, maybe you’ve got a big race coming up and you really don’t want to skip a workout. A good rule of thumb to decide whether or not you can go running while sick is the above-the-neck rule, Dr. Buttarazzi says.

Here’s how that works: If your symptoms are all above your neck—runny nose, congestion, sore throat—an easy run is likely OK. But “anything below the neck—chest tightness, body aches, stomach issues, fever—is a cue that you should be resting,” she says.

According to both doctors we spoke to, below-the-neck symptoms that should make you reconsider running include:

If you have any of these more severe symptoms, “it is better to allow your body to rest,” Dr. Gardner says.

Tips for Running While Sick

If your symptoms pass the above-the-neck rule and you decide you’re healthy enough to run, you’ll still want to keep a couple of important pointers in mind for your safety and comfort:

Can Running While Sick Worsen Your Symptoms?

Yes and no. You might feel a little worse during or after a run because “your body’s working hard already to fight off this virus,” Dr. Buttarazzi says. That especially might be the case if you attempt high-intensity running workouts, like interval runs, she adds.

But even though you might feel a little more run down, moderate exercise with a common cold won’t necessarily prolong or worsen symptoms. In fact, it may actually make the symptoms of an acute respiratory infection less severe, according to a 2020 Cochrane Library review, although this research has been mixed. “There are some studies suggesting that moderate exercise can help to increase production of specific white blood cells, which helps the body to fight infection,” Dr. Gardner says. “However, these cells can also launch an inflammatory cascade, which can further stress the system.”

As long as your symptoms are above your neck and you don’t push too hard, you’re probably in the clear for an easy run. “Light exercise during a cold, as long as it is guided by your body, generally will not worsen a cold, and can be good for the body and the mind,” Dr. Gardner says. “Just don’t overdo it!”

When Can You Return to Your Regular Running Routine After Being Sick?

When you get back into your usual running program also depends on your symptoms and energy levels. “Some people feel fine within a day or two, and for some people, it takes a week,” Dr. Buttarazzi says. 

Wait at least until your symptoms are all above your neck, “and you generally are getting through your typical day with some extra energy to spare,” Dr. Gardner says.

But don’t expect to jump right back into your hardest runs. “Gradually build back into it with slower, easier runs,” Dr. Buttarazzi says. Aim to start at around 50–75 percent of your typical intensity and duration, and gradually progress to your usual training, Dr. Gardner says. This way, if you start to feel like your symptoms are coming back or your energy is low, you can easily scale back and take a little more time off to recover, Dr. Buttarazzi adds.

The Takeaway

It’s generally safe to go running with a cold if your symptoms are mild and all above your neck, such as congestion or a runny nose. Even if that’s the case, it’s still best to run at a lower intensity than you might when you’re totally healthy. Avoid running in groups or at a gym where you could spread your germs, and listen to your body so you know when to ease up. 

If your symptoms are below your neck or more severe (such as fever or body aches), it’s best to take some time off running to truly rest. Wait until your symptoms are above your neck and your energy levels improve, then gradually ease back into your usual training routine.