How to Know When You’re Too Sick to Run

Ashley Lauretta
by Ashley Lauretta
Share it:
How to Know When You’re Too Sick to Run

Whether you’re in the thick of training or just a week out from your goal race, any little setback can seem like a major problem. Even something everyone loved as a kid — sick days — aren’t enough of an excuse to keep many runners from lacing up and heading out the door. But there can be a fine line between pushing through and laying low for a few days.

If you don’t have many symptoms it may seem like an overreaction to go see a doctor, however, according to the Centers for Disease Control and Prevention, “it can be difficult (or even impossible) to tell the difference between [a cold and the flu] based on symptoms alone.” If you’ve scheduled an appointment with your doctor — which is always recommended — and are waiting to get into the office to be seen, here’s what to know about whether to run in the meantime.


It can be easy to shrug off aches and pains, but paying attention to your symptoms is the best way to make sure you don’t make your illness worse — requiring even more time off — by running when you shouldn’t. A good rule of thumb is that if your symptoms are from the shoulders up, such as congestion or cough, you are usually OK to run. Anything from the shoulders down, including muscle aches or a chest cold, means you should take time off to rest. Of course, if you have a fever, it doesn’t matter where your symptoms are; take time off.

“Symptoms of the common cold can be runny nose, mild sore throat, mild cough and feeling fatigued or run down. In this case, a runner should make sure they maintain good hydration if they do some light exercise,” explains David Schechter, MD, a family and sports medicine physician in Culver City, California, and author ofThink Away Your Pain.” “However, a runner should not exercise if there is a fever or any significant chest symptoms like coughing up phlegm, shortness of breath or wheezing.”

It’s important to understand how your symptoms will affect your running even if you are cleared to stay active. Slowing down and paying extra attention to your fueling and nutrition is important, even if you are just suffering from a head cold. Now isn’t the time to train at the same high intensity as you would if you were completely healthy, as this can lead to symptoms sticking around longer.

“If you are trying to accomplish a specific training goal while feeling miserable and lacking energy, that is a poor choice; you’ll have a frustrating run and possibly slow recovery, delaying the day you can get back to ‘really’ training,” shares Jae Gruenke, Feldenkrais practitioner, running form expert and founder of The Balanced Runner. “In other words, if you don’t feel up to a run, don’t do it. You can really trust your body on this.”

Just as you are taught to listen to your body as you prepare for a race so you don’t overtrain, the same applies when you are sick. It can be tempting to push through, but most times, missing a day or two out of months and months of training isn’t enough of a setback to make or break your race day performance.


If you’ve taken even just a day off because of a cold and feel your symptoms are on the decline, you still want to take things slow as you return to activity. As stated, pushing yourself too hard can cause symptoms to return.

“The priority should be to get back to health and workout modifications in mileage and intensity are a must, including taking complete rest days,” urges Lisah Hamilton, coach and founder of The Conscious Runner. “It is better to miss a few workouts than to try to push through them. Doing too much, too fast, too soon when you are sick can prolong healing.”

As most symptoms subside, you are clear to run unless your fever remains or you have muscle aches. According to Dr. Schechter, muscle aches can be a sign the virus is still circulating in your body and exercising increases the risk of rare, but serious, complications. Otherwise, he says making sure to focus on pre- and post-run hydration helps flush out any virus or remnants of an illness that are present.


“As you start to recover — or perhaps if you’ve had a mild cold and are 3–7 days into the illness when it’s mostly nasal symptoms — running can actually help to decongest and allow the mucus and even phlegm to clear out of the body,” Schechter adds. “Just be prepared to spit and cough a little more on your run than usual.”

As you return to running — at a slower pace, as instructed above — it is important to pay attention to your form as that can suffer, as well. Gruenke notes that any lingering muscle stiffness and fatigue can impact how you move, causing you to feel stiff and heavy. This, she says, is another good reason to make your first few runs back intentionally short and easy.

“It’s a good idea to include some gentle mobility work when returning to running after a cold; for example, some gentle yoga, a low-key dance or calisthenic workout [remember the goal is mobility, not intensity!], swimming some laps of mixed strokes or revisiting a few favorite Feldenkrais (movement) lessons,” concludes Gruenke. “Even though it can feel like weakness or ‘giving in,’ listening to your body, being gradual and paying attention to your mobility will help ensure that you minimize the setback a cold represents.”


> Men’s Running Gear
> Men’s Running Shoes
> Women’s Running Gear
> Women’s Running Shoes

About the Author

Ashley Lauretta
Ashley Lauretta

Ashley is a journalist based in Austin, Texas. She is the assistant editor at LAVA and her work appears in The Atlantic, ELLE, GOOD Sports, espnW, VICE Sports, Health, Men’s Journal, Women’s Running and more. Find her on Twitter at @ashley_lauretta.


Never Miss a Post!

Turn on MapMyRun desktop notifications and stay up to date on the latest running advice.


Click the 'Allow' Button Above


You're all set.

You’re taking control of your fitness and wellness journey, so take control of your data, too. Learn more about your rights and options. Or click here to opt-out of certain cookies.