Should You Really Work Out When You’re Sick?

We’ve all been there. Whether you’re this close to hitting a seven-minute mile, you’re one week into a brand-new Zumba® class or you just started making power walks after lunch your thing, that bug you woke up with couldn’t have come at a worse time.

You don’t want to lose your momentum, especially if you’re not that sick. But you also don’t want to make yourself feel any worse than you already do. And what if you’re contagious?

Can you work out while you’re sick?

If you’re debating between hitting the gym or hitting the medicine cabinet, sports health physician Vikas Patel, DO, says it may be time to conduct a “neck check.”

When you can work out vs. when you can’t

A “neck check” isn’t exactly what it sounds like, but it’s close. If your symptoms are above the neck ― sore throat, coughing, sneezing or runny nose ― it’s typically OK to still work out. But if your symptoms are below the neck ― chest congestion or hacking cough, muscle aches, fatigue or upset stomach ― it’s a good idea to rest.

If you pass the neck check and want to try to power through a workout, Dr. Patel suggests cutting your effort by about 50%. Walk instead of run. Do one set instead of five. Or try a low-impact activity like yoga.

Exceptions to every rule

While generally helpful, the neck check isn’t foolproof.

If you have a fever, you 100% shouldn’t be exercising. And if you have asthma or a heart condition, Dr. Patel recommends speaking with your physician before exercising.

Listen to your body

While the neck check might suggest it’s OK to get your blood pumping, you shouldn’t feel obligated to power through a workout if you’re not feeling well.

“The general rule of thumb is to listen to your body,” Dr. Patel says. “Taking a few days off won’t impact your fitness level.”

In fact — as any top athlete with tell you — good exercise routines build in opportunities to rest and recover.

Should certain exercises always be off the table when you’re ill?

There’s no hard and fast rule about what you can and can’t do when you’re sick, but common sense tells us that you should:

• Stay out of the pool if you’ve GI issues. If you have diarrhea, stay far away from the pool. You could contaminate the water with cryptosporidium. The U.S. CDC recommends avoiding the water until you’ve gone a full two weeks without diarrhea.
• Avoid team sports, group activities and gym visits. You don’t want to make other people sick.
• Reduce exercise intensity. Avoid activities that are likely to exhaust and dehydrate you. Regardless of what you’re doing, be sure to reduce the amount of effort you’re putting in by about 50%. Your body needs the other 50% to fight off whatever’s making you sick.
• Deprioritize endurance. In addition to reducing the intensity of your workout, make sure you’re reducing the duration, too. A workout doesn’t have to be long to be beneficial.
• Try to sweat less. You don’t want to get dehydrated, so skip the hot yoga — or anything else that’s likely to turn you into a puddle.

Hydration is key

Exercise may be optional when you’re sick, but making sure you drink enough water isn’t.

According to Dr. Patel, it’s even more important to focus on hydration when you aren’t feeling well. “Most people who felt like working out, who had prolonged their sickness, were actually feeling the effects of dehydration,” he notes.

Are you putting others at risk?

When it comes to working out while sick, it’s important to be mindful of other people’s safety — not just your own. That means avoiding gyms, exercise classes and team sports.

When is it safe to go back to the gym?

Whether you have the flu, COVID-19, or a run-of-the-mill cold, it’s important to remember that you could be contagious longer than you realize. Follow the guidelines below for when it’s safe to return to the gym — and when in doubt, work out at home.

The flu

If you have the flu, you were already contagious before your symptoms showed up. You’ll be most contagious during the first three or four days thereafter.

You can spread the flu for up to a week after your symptoms start. Children and adults with weakened immune systems may be contagious even longer.

The common cold

The common cold can be even more infectious than the flu. Most people are contagious one to three days before first experiencing symptoms, and can stay that way for up to two weeks.

Your best bet is to wait at least 72 hours after your symptoms have resolved to return to the gym.

Is exercise good for a cold?

You’ve probably heard that you can “sweat out” a cold. But that’s not true.

While exercise is good for your immune system, that’s a cumulative effect over time. Put differently, consistent exercise may reduce the number of colds you get in general, but once you’re sick, your body’s immune response is what it is.

Some people may feel better if they do some light exercise with a cold, but it can also make your symptoms worse if you aren’t careful.

COVID-19

If you have COVID-19, the CDC recommends isolating for at least five days after the day you test positive and taking precautions like indoor masking for at least 11 days. To ensure the safety of your workout buddies, though, it’s best to wait until you’ve had two negative tests in a row, 48 hours apart, before hitting the gym.

When you do go back

When the time comes for you to return to the gym, your team or your favorite exercise class, keep in mind that there are many ways you can reduce the risk you pose to others, from wearing a mask and washing your hands, to bringing your own equipment with you and sanitizing the surfaces you touch.

To reduce your risk, keep listening to your body. If you don’t feel like you have the energy or strength for all those burpees, try jumping jacks instead. If you need to sit out the climbing portion of your cycling class, sit it out. And if you need to skip your workout and take a nap instead, don’t hesitate.

And if — after reading this — you have any lingering doubts about the wisdom of returning to your regularly scheduled exercise routine, speak with a doctor.