Is it safe to exercise while sick?

Is it safe to exercise while sick?

When a deep winter cold — with its perfectly pleasant symptoms like a runny nose and constant sneezing — hits you like a ton of bricks, you might be wondering if it's a good idea to continue with your daily exercise routine. While a little exercise sounds rejuvenating after lounging on the couch all day, is exercising while sick actually what the doctor would order?

Here, an exercise physiologist answers exactly this question. She also explains how to stay safe and recover properly if you choose to do so while you're sick.

Should you exercise when you're sick?

If you want to exercise while sick, there's good news: For the average person, it's usually safe to exercise while you're sick if you have symptoms that appear above the throat, such as a runny nose, headache, nasal congestion, or sneezing, says Heather A. Milton, MS, RCEP, CSCS, a board-certified clinical exercise physiologist at NYU Langone Health's Sports Performance Center.

In fact, it can even help you feel better when you're sick, says Milton. As you exercise, your body releases the hormones and neurotransmitters epinephrine and norepinephrine, both of which increase your heart rate and contractility (the force of your heart's contractions) and increase your breathing rate, she explains. According to the Cleveland Clinic, your muscles receive better blood flow and oxygen, and your airways open to take in more oxygen. And this flowing movement can just make you feel more alert, says Milton. Your workout will also give you a shot of dopamine, a neurotransmitter and hormone that can improve your mood, which may be just what you need after sneezing in bed all day, she says. (It should go without saying, but you shouldn't exercise with others while you're sick with a contagious illness, so stick to solo workouts if that's the case.)

However, according to the Mayo Clinic, you should skip your workout if you have chest congestion or a cough. The same rule of thumb applies when you're dealing with a fever, says Milton. ICYDK, when you're dealing with an infection, your body may temporarily raise your temperature to try to kill the harmful virus or bacteria, according to the National Library of Medicine. “If you have a fever, you are temporarily immunocompromised,” adds Milton. “And there is a very, very short window of time after exercise where your immunity is reduced.” This dual immune deficiency can make you more susceptible to other illnesses, so it's best to stay home, she explains. (FTR, exercise improves your immune system over time, so this temporarily compromised state shouldn't be a reason to skip your workout entirely, she adds.)

How long does it take to lose muscle?

How to exercise safely while you're sick - and recover properly

Even if your symptoms occur above the neck and you feel fit enough to exercise during the illness, you should not undertake incredibly strenuous exercise. Instead, stick to low- to moderate-intensity exercises (think light jogging, a basic strength workout, a yoga practice) that are easy to complete, as you may feel a little more tired than usual. The higher the intensity of your workout, the more likely you are to experience a temporary drop in immunity afterwards - and therefore have a greater chance of catching another disease - says Milton.

You should also avoid straying from your usual routine, suggests Milton. "You can do a slow, steady, hour-long workout if you're used to it, but this is definitely not a time to try to do anything outside of your normal," she adds. Translation: Wait until you're disease-free to do your first powerlifting workout or intense bout of treadmill sprints.

As you move through your workout, keep track of how you feel; If you develop lightheadedness, increasing shortness of breath, nausea, or a racing heart, that's your cue to stop exercising, says Milton. During and after your training session, remember to keep an eye on your H2O consumption. “It is always recommended to increase fluid intake when you are sick,” says Milton. "When your immune system is fighting an infection and you use metabolism [physical and chemical processes in the body that convert or use energy], you use water," she explains.

This fluid intake, combined with the water you lose through sweat during exercise, means it's especially important to stay hydrated. The exact amount of fluid you need varies from person to person, depending on the infection, your body weight, and other factors, says Milton. Your best bet: Aim to drink at least 11.5 cups of fluid per day, the basic recommendation for an average, healthy adult living in a temperate climate, and then increase your intake to account for your sweat and immune system processes. In general, you should drink an additional 16 ounces of fluid for every pound of sweat you lose, as Shape previously reported.

Whether you're suffering from a nasty cold or just feeling under the weather, sleep is a must, says Milton. Just four hours of sleep a night reduces the activity of natural killer cells, a type of immune cell that can kill virus-infected cells and tumor cells, which can increase the risk of viral infections, according to the Centers for Disease Control and Prevention. And sleep deprivation can also negatively impact fitness performance factors like reaction time, submaximal strength and endurance, according to research. “Sleep is always overlooked, but it is an essential part of recovery when you are sick or well,” adds Milton.

Even if exercising during an illness is physically safe for you, you shouldn't force yourself to exercise if you're not feeling it mentally. Your dumbbells and running shoes can wait until you get back to your fully healthy self.

How to start exercising again after an illness