Exercising When Sick: What to Know About Sticking to Your Gym Routine if You’ve Got the Sniffles (or Worse)

Should you exercise when sick? It’s the million-dollar question, especially during the colder months. The answer? As with just about everything related to health and wellness—it depends.

Working out while sick is not necessarily dangerous, but can be a deterrent to your fitness goals in some cases. Here’s what the science says, and how you can modify your routine accordingly.

Should You Exercise When Sick?

Is it bad to workout when sick? No. In fact, according to the American Heart Association, exercise can be a mild analgesic; working out increases blood circulation and clears your airways. 

Physical activity is a bit like medicine, in a sense—take too much, and you’ll actually feel worse. But if you get the dosage right, exercising while sick might speed up your recovery.

In a 2022 narrative review on the topic, researchers had this to say: 

• “Although high-intensity exercise can suppress the immune system … moderate-intensity exercise can improve immune function and maintain physical fitness.”

This prescription has been corroborated by other data, which collectively support the dose-response relationship between illness and exercise. Does exercise help with a cold? The simple answer: Yes, but with caveats.

Symptom Guidance: When to Avoid Your Workout

The research is pretty clear. Per WebMD, exercising while sick is not inherently bad, and may be a boon to your recovery time if you take it easy and don’t have aggressive symptoms. So, what are the symptoms worth watching out for?

Symptoms to Watch Out For

The golden rule: If your sickness symptoms are mostly above the neck—think mild headache, congestion, or a light cough—you’re good to go, says the Cleveland Clinic. However, if you’re experiencing more comprehensive issues such as

• Chills or body aches
• Stomach cramping
• Nausea, diarrhea, or vomiting
• Disorientation 
• Severe headache

It’s best to stay home from the gym. This goes double if you’re running a fever. Do you burn more calories when sick? If you’re running a fever, it might feel like it, but elevated body temperature can wreak havoc on your body’s systems. 

Fever, plus symptoms like aches or cramping, can interfere with your exercise performance and thus your caloric expenditure, resulting in fewer calories burned despite feeling like a furnace.

Logistics That Matter

Your body’s internal climate isn’t the only thing that matters when you’re asking yourself whether it’s worth it to risk a workout. If you work out at an indoor, public facility, you should not exercise while sick. 

Studies tell us that, even when adhering to proper sanitation protocols, gyms are particularly prone to the transfer of germs and bacteria. 

Moreover, you should also consider factors like

• Air circulation (open-air vs. enclosed)
• Temperature 
• Access to medical supplies

These and more can impact how you feel moment-to-moment during a workout. Cold, dry air—think a garage gym in January in the Midwest—could do more harm than good for your symptoms, even if the workout you’re doing is modest and in the privacy of your own home.

Workout Modifications When Sick

Let’s be real: If you’re a gym rat, skipping the gym on account of the sniffles can feel like sacrilege. Whether you’re battling a runny nose or something more serious, you need to know how to modify your workout while sick if you’ve already committed to hitting the gym.

One more time—if you’re showing symptoms, avoid public gyms for both your own health and the public good. That said, if you were going to train, you should know how to pare things down.

Reduce Intensity & Volume

For your immune system, it’s one battle after another while you’re sick. You can do your part in that biological war by not starting a new conflict on a different front. Put simply; reduce your workout intensity and volume while sick to avoid overwhelming your body. 

This goes for both weights and cardio. Does your heart rate increase when sick? Yes; you don’t want to add to the load on your heart by trying for a new personal best time in your favorite metcon or HIIT circuit. 

Keep It Simple

Sicknesses can be disorienting. Dehydration and even a mild fever can strongly affect your spatial awareness and coordination, so it’s best to avoid complex movements or extended circuits while sick. 

This includes things like Olympic lifting, advanced calisthenics, or even unilateral training, which can really amp up your heart rate even if you keep your reps low and load in check. Instead, opt for basic or beginner moves that you can perform on autopilot. 

Stay Cool, Stay Indoors

Outdoor exercise is, broadly, a huge benefit to your health. This applies when you’re feeling a bit under the weather, but depends on your local climate. If it’s cold outside or arid where you live, avoid the outdoors while exercising so as to not stress your respiratory system; a sore throat can be agitated by wintry air.

On the other end of the spectrum, extreme heat is a no-go. Hitting the sauna or cranking up the heat might help loosen stuck mucus, but can also amplify or even trigger other symptoms. 

Prioritize Hygiene

This one is obvious, but bears repeating. Whether you’re exercising at home or in a gym, hygiene should be your number-one priority. Sanitize all contact surfaces, drink a bit more water than usual, and consider an electrolyte beverage or small snack — like a high protein bar — if you’re prone to feeling queasy. 

Takeaway 

So, what’s the verdict—should you exercise when sick? The short answer is it’s generally fine, provided you take it easy. Think of mild sickness as a speed bump; slow things down for just a moment, and you’ll glide right over it. Maintain or pick up speed and you may do long-lasting damage. 

If you’re on the fence, stay home. Get cozy, get medicated, and wait it out. There’s no harm in treating a few days of sickness as an impromptu deload. When you get back to the gym (it’s not going anywhere), your body might even thank you for it. 

FAQs

Is it better to work out or rest when you are sick?

Whether you should work out or rest while sick depends on your symptoms. If you have mild symptoms generally localized above your neck, it should be fine to partake in a light workout. Otherwise, play it safe and rest. 

Does working out help get rid of a cold faster?

In some cases, yes, working out can help get rid of a cold faster. Cardiovascular exercise improves blood circulation and enlarges your airways to help utilize more oxygen in less time. 

Is cardio better than weights while sick?

It depends on your symptoms, but cardio and weights are both okay to do while sick provided you keep your intensity low. Heavy lifting can aggravate body aching from sickness, and intense cardio can tax your heart while it’s already working overtime fighting the illness. 

References

1. Agha-Alinejad, H.; Ahmadi Hekmatikar, A.H.; Ruhee, R.T.; Shamsi, M.M.; Rahmati, M.; Khoramipour, K.; Suzuki, K. A Guide to Different Intensities of Exercise, Vaccination, and Sports Nutrition in the Course of Preparing Elite Athletes for the Management of Upper Respiratory Infections during the COVID-19 Pandemic: A Narrative Review. Int. J. Environ. Res. Public Health 2022, 19, 1888.

2. Campbell JP, Turner JE. Debunking the Myth of Exercise-Induced Immune Suppression: Redefining the Impact of Exercise on Immunological Health Across the Lifespan. Front Immunol. 2018 Apr 16;9:648. doi: 10.3389/fimmu.2018.00648. PMID: 29713319; PMCID: PMC5911985.

3. da Silveira MP, da Silva Fagundes KK, Bizuti MR, Starck É, Rossi RC, de Resende E Silva DT. Physical exercise as a tool to help the immune system against COVID-19: an integrative review of the current literature. Clin Exp Med. 2021 Feb;21(1):15-28. doi: 10.1007/s10238-020-00650-3. Epub 2020 Jul 29. PMID: 32728975; PMCID: PMC7387807.

4. Goldhammer KA, Dooley DP, Ayala E, Zera W, Hill BL. Prospective study of bacterial and viral contamination of exercise equipment. Clin J Sport Med. 2006 Jan;16(1):34-8. doi: 10.1097/01.jsm.0000181436.41268.1f. PMID: 16377973.

Jake Dickson holds a B.S. degree in Exercise Science and is a NASM-CPT. As a health & wellness writer, Jake focuses on making fitness practical and accessible for any audience. Off the clock, you can find Jake at the gym or unwinding by the beach.

This article was reviewed by Rosie Borchert, NASM-CPT, for accuracy.