Key takeaways:
Regular exercise can boost your immune system and lower your risk of infections.
Mild-to-moderate exercise is generally safe when you have a mild illness like a cold. But it depends on how bad your symptoms are.
Always listen to your body and consult a healthcare professional if you’re not sure about working out while sick.
Feeling under the weather but want to squeeze in your usual workout? Your commitment to a fitness routine is understandable. After all, regular exercise is good for your health and well-being.
It’s typically safe to do mild or moderate exercise when you have a cold. But there are some key exceptions. Learn how exercise can affect your recovery and when it’s time to give your body a rest.
Should you work out when sick?
It depends on how you’re feeling and intensity of exercise. Research suggests that exercise is OK if you have mild symptoms. For example, with an upper respiratory tract infection like a cold, you may have symptoms like:
Coughing
Sneezing
Stuffy or runny nose
Earache
Sore throat
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If you only have these mild symptoms, you may still be able to do low- or moderate-intensity exercise like walking or jogging.
Signs you should stop exercising while you’re sick
If you have other symptoms, give your body a rest so it can fight off more serious infections. Here are some signs that you may need to take a break from your exercise routine:
Painful body aches: Sore muscles or painful body aches may indicate more severe illness. Exercising with body aches can lead to fatigue or exhaustion.
Mucus-producing coughs: Exercising with a wet, mucus-producing cough could cause shortness of breath or fatigue.
Fever: Working out with a fever can cause a severe increase in your already elevated body temperature. This is one risk of working out when you have the flu.
Diarrhea or vomiting: Abdominal symptoms like vomiting or diarrhea increase fluid loss, so sweating during a workout could put you at risk for dehydration.
Trouble breathing: If you’re having trouble breathing, experience chest tightness, or shortness of breath, it’s a sign your body isn’t up for working out.
Dizziness: Dizziness is often a sign of overexerting yourself or dehydration. While sick, you want to avoid this.
Feeling lightheaded: Feeling faint or lightheaded can be another sign your body is overworked and you’re not quite ready for exercise.
You should always listen to your body. It’s the best guide when deciding whether to exercise while you’re sick. If you’re feeling under the weather and the thought of exercising seems taxing, it’s probably best to skip your workout. But if you’re still unsure about working out with a cold, contact your primary care provider.
What kind of exercise is OK when you’re sick?
If you work out with a cold or other mild illness, start with low- or moderate-intensity exercise. Consider the following exercises when you have mild cold symptoms above the neck:
Light cardio or jogging
Short, low-impact strength training
The goal is to prevent overexertion by keeping your intensity and heart rate low. So, avoid the following exercises when you have a cold:
High-intensity interval training
Endurance or distance running
Sprinting or power work
Weightlifting
Bacteria and other bugs can spread from touching equipment and breathing shared air in a gym. So, it’s best to avoid the gym if you might be contagious. You can take your training outside if the temperature is moderate and you can keep your distance from others.
How much exercise is OK when you’re sick?
Start small if you’ve been sick for a few days but feel well enough to do some exercise. Limit the length of your workouts and let your body guide you. If 20 minutes of an activity like walking or stretching sounds doable, it may leave you feeling better. It’s also a good idea to limit the intensity of your workouts.
Take a gradual approach when returning to your usual fitness routine. Consider easing back based on the number of days you were sick.
For example, if you were sick for a week, try halving the amount of exercise you usually get for 3 to 4 days. After that, you can ramp up your workouts until you feel ready to tackle your regular exercise routine.
Can you sweat out a cold?
There’s no evidence that sweating can get rid of a cold faster. Sweating simply helps your body stay cool. And there isn’t enough research to confirm that exercise increases or decreases cold recovery time. Many factors — like the frequency, duration, and intensity of your workouts — might affect your recovery from a cold.
Listening to your body and focusing on lifestyle factors may ease your symptoms and help you feel better sooner rather than later. Adequate sleep, a well-balanced diet, and low mental stress can improve your recovery and overall health.
How long should you wait to exercise after being sick?
There’s no hard-and-fast rule about when to start exercising again after a cold. Symptoms usually last 7 to 10 days, but they can linger for up to 3 weeks. You can ease into exercise when your symptoms improve or resolve and you feel up to it.
A cold stresses the immune system, and the added physical demands of exercise could do more harm than good. Overdoing it by exercising before you feel well enough could affect your immune response. Some research shows a link between frequent intense exercise and an increased risk of illness.
That’s why monitoring your symptoms and listening to your body is so important.
How does working out affect immune function during sickness?
You are less likely to catch a cold and other infections if you exercise regularly. Several studies have found an increase in certain immune cells and antibodies in adults who do so. Experts believe regular exercise makes your immune system more responsive and effective.
So the added physical stress your body experiences during moderate exercise may boost immune health. But remember: If you feel weak or exhausted due to illness, it’s better to rest instead of sweating it out.
Frequently asked questions
Most people won’t lose much muscle mass if they take a break due to mild illness. Studies show that loss of muscle mass doesn’t happen for many weeks, even in older adults. You may be more likely to lose aerobic fitness. One study asked sedentary men to participate in a fitness program, and then told them to stop for 2.5 weeks. They didn’t lose muscle mass after the 2.5 weeks, but they did lose aerobic fitness.
It’s OK to lay in bed for a day or two, especially if you have a bad cold or flu. If you have the flu or body aches and feel exhausted, resting in bed may be all you’re up for. But if you start to feel a bit better, it’s a good idea to get up and move around. Moving around may help clear nasal congestion, and it can help you maintain your strength and energy.
It’s hard to say if you burn more calories when you’re sick. It’s thought that having a fever increases your metabolism, which would lead you to burn a few more calories. But if you’re also lying in bed or generally being less active, you’re probably burning fewer calories than you do when you’re well and active.
It’s not a good idea to work out if you have bronchitis. Bronchitis causes inflammation in the airways of the lungs. This makes it hard to breathe and triggers a lot of coughing. So anything that challenges your breathing — like exercise — can make bronchitis feel worse. Bronchitis is also contagious. So, if you do decide to move your body, be sure to do it outside and keep your distance from others.
Working out with a sinus infection is a bit different than working out with a cold. A sinus infection can cause headache, facial pain and pressure, and a fever. As above, it’s best to rest if you have a fever. And other sinus infection symptoms can affect your balance and endurance, making exercise more risky.
Most people won’t lose much muscle mass if they take a break due to mild illness. Studies show that loss of muscle mass doesn’t happen for many weeks, even in older adults. You may be more likely to lose aerobic fitness. One study asked sedentary men to participate in a fitness program, and then told them to stop for 2.5 weeks. They didn’t lose muscle mass after the 2.5 weeks, but they did lose aerobic fitness.
It’s OK to lay in bed for a day or two, especially if you have a bad cold or flu. If you have the flu or body aches and feel exhausted, resting in bed may be all you’re up for. But if you start to feel a bit better, it’s a good idea to get up and move around. Moving around may help clear nasal congestion, and it can help you maintain your strength and energy.
It’s hard to say if you burn more calories when you’re sick. It’s thought that having a fever increases your metabolism, which would lead you to burn a few more calories. But if you’re also lying in bed or generally being less active, you’re probably burning fewer calories than you do when you’re well and active.
It’s not a good idea to work out if you have bronchitis. Bronchitis causes inflammation in the airways of the lungs. This makes it hard to breathe and triggers a lot of coughing. So anything that challenges your breathing — like exercise — can make bronchitis feel worse. Bronchitis is also contagious. So, if you do decide to move your body, be sure to do it outside and keep your distance from others.
Working out with a sinus infection is a bit different than working out with a cold. A sinus infection can cause headache, facial pain and pressure, and a fever. As above, it’s best to rest if you have a fever. And other sinus infection symptoms can affect your balance and endurance, making exercise more risky.
The bottom line
If you have a cold but aren't sure if you should continue exercising, let your symptoms guide you. Generally, mild-to-moderate exercise is usually OK if your symptoms are above the neck. But symptoms below the neck may mean that you need to rest. Your body will tell you whether to rest or sweat with a cold. But if you’re still unsure, ask your primary care provider for advice.
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References
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