Exercise when sick: Should you sweat it out? Or rest and recover? |

An important question, deserving of some contemplation. One is for the person who is sick, and the other is for the person who is healthy. If you are sick: Should you try to exercise? Should you take medicine and rest? My answer to both: yes. If you are healthy: Should you exercise? Should you take medicine and rest? My answer to both: no.

Since I have a history of getting sick and I’m often freaking out about it, I have a hard time exercising. I get so paranoid about getting sick that I don’t want to sweat it out in the gym because I’m not sure if I’ll be able to make it through the workout. But how can I exercise when I’m sick? I know there are some professionals out there who say that you should go to the gym when you’re sick, but what about the rest of us?

When you’re sick, everyone knows that you should rest and recover. However, is that what you should do? Another popular theory is that when you’re sick you should exercise to boost your immune system. However, there is actually a lot of evidence to support both of these options. According to the CDC, exercise will help you fight off a cold/flu better, but it won’t improve the chances of getting the flu. If you’re feeling better, you could stop exercising.

Everyone becomes ill at some point. But it’s difficult to know what to do; should you workout while you’re ill or not?

Is it a good idea to “work it out”? Alternatively, why not get some rest?

We’ll clarify things up in this article. You’ll know what to do the next time you have the flu or a cold.

Your friendly local fitness center. You’ve warmed up and are prepared for a fantastic exercise.

Then Mr. Sneezy appears out of nowhere. Coughing, sniffling, and mouth-breathing were all present. He’s splattering paint all over the carpets and seats.

“Why don’t you simply remain at home and rest?” you’re pondering

(And, while you’re at it, why don’t you stop passing around those terrible germs?)

Mr. Sneezy, on the other hand, may be onto something. Perhaps he’ll be able to sweat the illness out of his system while also strengthening his immune system.

What is the best course of action? Let’s have a look.

A short and dirty introduction to the immune system

Bacteria, viruses, fungi, and parasites attack us every day. It’s a germ jungle out there, folks!

Upper respiratory tract invaders, or URTIs, are the most frequent intruders. Yes, I’m referring to

  • colds,
  • coughs,
  • influenza,
  • sinusitis,
  • tonsillitis,
  • infections of the throat, and
  • Infections in the middle ear

Fortunately, our immune system has a strategy in place. When confronted with a foreign assault, it works tirelessly to protect us. We’d never have a healthy day in our lives if it weren’t for the immune system.

The bone marrow and thymus are the origins of our immune cells. Through the lymph nodes, spleen, and mucous membranes, they interact with invaders.

This means they come into touch with you first in your mouth, stomach, lungs, and urinary tract.

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The immune system’s innate and adaptive responses

Our non-specific initial line of defense is our innate (natural) immune system.

It includes:

  • obstacles of a physical or structural nature (like the mucous lining in nasal passages),
  • chemical barriers (such as the acids in our stomachs) and
  • Protective cells (such as our natural killer (NK) cells, which are white blood cells capable of killing dangerous intruders).

When we’re young, our immune systems are still developing.

Women, interestingly, have a higher total innate immunological response than males. (Perhaps this is why women frequently outperform males when it comes to colds.) However, autoimmune illnesses strike them more often.)

The adaptive (acquired) immune system is the next step.

This is a more complex system made up of cells and processes that are highly specialized. When the innate immune system fails, it activates.

By preventing pathogens from colonizing and eliminating microorganisms such as viruses and bacteria, the adaptive immune system aids in the battle against infection.

The T and B cells should be activated. The thymus and bone marrow are where these specialized white blood cells develop. They also have a sort of memory, believe it or not.

It is because of this recollection that they are so effective. They mobilize more efficiently to combat a particular disease if they “recognize” it.

This is what we mean when we say “immunity building.”

Have you ever wondered why children are more susceptible to infections than adults? Their adaptive immune systems are less developed since they haven’t received as much exposure.

Furthermore, vaccination is based on the acquired immune response. If you give your body a little amount of a disease, it will know what to do if you give it a larger quantity.


When you’re ill, should you exercise?

Let’s get one thing straight right away: there’s a distinction to be made between “working out” and “physically moving the body.”

A planned exercise program that involves heavy breathing, sweating, working hard, and experiencing some pain triggers the body’s stress response.

Our bodies can readily adjust to stress when we are healthy. This gradual adaptation is exactly what makes us fitter and stronger over time.

When we’re ill, though, the stress of a strenuous exercise may be too much for our immune systems to manage.

Even yet, there’s no need to rush to the sofa as soon as the sniffles appear. Unless you’re badly out of shape, non-strengthening exercise shouldn’t harm you — and may even benefit you.

What do I mean when I say “non-strengthening movement”?

It may, for example, include:

  • jogging (preferably outdoors),
  • Bike riding at a low intensity (again, outdoors) ,
  • gardening,
  • T’ai Chi is being practiced.

All of these activities, in fact, have been proven to improve immunity. 

They aren’t strong enough to put the body under severe immune-compromising stress. Instead, they often assist you in feeling better and recovering quicker when you are ill.

When it comes to colds, Dr. Berardi frequently advises low-intensity non-panting “cardio.” These exercises seem to be beneficial when done with little heart rate increase and ideally outdoors.

What about “exercising”?

Non-strengthening movement and working out for a specific goal are two distinct things.

Furthermore, as you are likely aware, not all exercises are made equal. There are low- and high-intensity exercises, as well as a variety of workouts in between.

However, what one person considers low may be considered great by another. So, how do you determine what degree of exertion qualifies as strenuous?

Allow your own sense of effort to be your guide.

A low to moderate intensity exercise will leave you feeling energetic in general. A high-intensity exercise, on the other hand, will kick your ass.

It makes sense to avoid the asskicking if you’re ill.

Let’s look at why it is.

What effect does exercise have on the immune system?

Both our innate and adaptive immune responses may be aided by exercise.

Here’s how to do it:

  • We are more vulnerable to infection after a lengthy period of intense activity. Running a marathon, for instance, may temporarily suppress the adaptive immune system for up to 72 hours. This is why so many endurance athletes get ill shortly after completing a race.
  • A single bout of intense exercise, on the other hand, does not have the same immune-suppressing impact. Furthermore, in healthy people, only one moderate-intensity exercise session may really improve immunity.
  • Chronic resistance training, interestingly, seems to boost innate (but not adaptive) immunity. Chronic moderate exercise, on the other hand, seems to enhance the adaptive immune system.

Finally, here’s the pattern:

  • Over time, regular, moderate exercise and resistance training may help to improve the immune system. So go ahead and workout hard while you’re still healthy.
  • Single high-intensity or long-duration exercise bouts, on the other hand, may impair immunological function. So, if you’re feeling under the weather, take it easy.

Exercise, stress, and immunological function are all factors to consider.

A group of experts studying exercise habits and influenza discovered the following:

  • People who did not exercise frequently become ill.
  • The those who exercised once a month to three times a week performed the best.
  • People who exercised more than four times a week were the most likely to get ill.

The J-shaped curve hypothesis comes into play.

Simply said, being sedentary or too active may decrease immunity, while anything in the center can boost immunity.


The importance of stress

Exercise isn’t the only thing that has an impact on your immune system. Stress also has a significant impact.

Let’s look at the many stresses that a person may encounter on any given day.

  • Exercise, sports, physical work, illness, and other forms of physical stress
  • Relationships, job, finances, and other sources of psychological stress
  • Hot, cold, dark, light, pollution, altitude, and other environmental stresses
  • Drugs, nutrition, cleanliness, and other aspects of one’s lifestyle may all cause stress.

Stress sets off a chain reaction of hormonal alterations that may lead to long-term immunological abnormalities.

  • Acute stress (lasting minutes to hours) may be good for your immune system.
  • Chronic stress (which may last from days to years) can be a major issue.

So, if you’re angry, concerned, or frightened every day for weeks, months, or even years, your immune system is being weakened. You’re also more prone to get ill.

Illness and anxiety

It goes without saying that if you’re unwell and battling an illness, your immune system is already under duress.

You may just overwhelm yourself if you add the stress of continuous intense exercise. That will make you feel much worse.

In addition, your immune system’s response to exercise may be influenced by your history of illnesses. The common herpes simplex virus, varicella zoster, and CMV, as well as hepatitis and HIV, are all examples.

A healthy body may be able to adapt to all of this. A body battling an illness, on the other hand, is not a healthy body.

Infection and overtraining

Furthermore, abrupt changes in exercise volume and/or intensity may generate additional stress, enabling a new virus or bacterium to take root and start a new illness.

Consider the 1987 Los Angeles Marathon, in which one out of every seven participants fell ill within a week after the event. Those who ran more than 60 miles per week before the event had double the chance of becoming ill as those who ran fewer than 20 miles per week.

This also seems to function in the other direction. In certain cases, chronic infections are a symptom of overtraining.

Learning from cancer & HIV

Because of how it affects the immune system, exercise therapy is often advised for cancer patients. Exercise seems to boost the activity of NK cells and lymphocyte proliferation. In other words, it seems that exercise may be beneficial.

In HIV patients, exercise seems to help reduce muscle loss, improve cardiovascular health, and improve mood. We don’t know how this works, but it may aid in the growth of CD4+ cells.

Other variables that influence immunity

Aside from stress, a variety of other variables may influence our immunity, and they can combine with exercise to either provide more protection or make us more susceptible to illness.

Some of these have previously been mentioned. Here are a few more examples.


As we age, our innate immune response may deteriorate. The good news is that being physically active and eating a healthy diet may counteract many of these effects.


The immune system’s response to exercise may be influenced by the menstrual cycle and the usage of oral contraceptives. Estrogens tend to boost immunity, while androgens decrease it. (Again, this may explain why women seem to handle colds better than males.)


Immune function is harmed by poor sleep quality and/or chronic sleep loss.


Exercising in extreme heat or cold does not seem to be much more stressful than exercising in a climate-controlled setting.

Exercising in a slightly cooler atmosphere, for example, may help the immune system. Hypothermia, on the other hand, may impair immunological function. In individuals with weakened immune systems, utilizing a sauna or hot bath may help to boost immunity.


Higher altitude exposure has a little impact on immunity.


In terms of immunity, it’s unknown how fat people react to exercise. Their immunological response to exercise may be blunted or exaggerated by changes in insulin sensitivity and inflammation during rest.


Immune changes have been shown to influence mood and inflammation. Patients with illnesses that have increased inflammatory activity are two to three times more likely to develop clinical depression.

(It’s worth noting that moderate exercise seems to be anti-inflammatory in those who have inflammatory diseases.)


Some people’s IL-6 (a chemical released after continuous intense activity) may be generated abnormally, resulting in tiredness, flu-like symptoms, and a sad mood.

Age of training

The better your body is at handling exercise, the more “trained” you are. To put it another way, it isn’t as stressful.

In case you missed the preceding statement, a greater degree of fitness is protective since it may reduce the stress reaction to exercise.

Guidelines for exercising when ill from a textbook

  • Day 1 of illness: Only little activity due to symptoms such as sore throat, coughing, runny nose, and congestion. When you have muscle/joint discomfort, a headache, a fever, malaise, diarrhea, or vomiting, don’t exercise at all.
  • Day 2 of illness: If body temp >37.5-38 C, or increased coughing, diarrhea, vomiting, do not exercise. If no fever or malaise and no worsening of “above the neck” symptoms: light exercise (pulse <120 bpm) for 30-45 minutes, by yourself, indoors if winter.
  • Day 3 of illness: If fever and symptoms still present: consult doctor. If no fever/malaise, and no worsening of initial symptoms: moderate exercise (pulse <150 bpm) for 45-60 min, by yourself, indoors.
  • If there is no symptom alleviation on day four of the sickness, don’t exercise. Consult a physician. Wait 24 hours after the fever and other symptoms have subsided before returning to activity. Go to the doctor if you develop new symptoms.

It’s important to keep in mind that certain diseases may signal severe infections. Consult your doctor if you aren’t feeling better or recovering.

Also keep in mind that you should ease back into activity in proportion to how long you’ve been ill. If you had been unwell for three days. Take three days to get back into the swing of things.

Young couple hiking in nature. Sport and exercise.

To exercise or not to exercise? What the experts advise

You now have a basic understanding of the immune system and how exercise affects it. However, you may still be unsure whether or not you should exercise when unwell. I sought advice from some of the finest in the industry.

The consensus is to follow your symptoms and apply common sense. Also, keep in mind the difference between exercising and working out.


Nick Tumminello is a musician from New York City.

I follow the general rule that if it’s above the neck, I can train it, and I can train it hard. Simply wash your hands before touching any of the equipment to avoid infecting others at the facility with your cold. Anything below the neck should be avoided at the gym, and you should take it easy until the finish.


Alwyn Cosgrove is a British actor.

We don’t like it when individuals train while they are sick. I don’t see any benefit in doing so.


Bryan Walsh, M.D.

Allow your symptoms to lead you. Go for a stroll or some mild exercise if you feel like it. It’s probably OK if you want to do some lower weight, higher rep work simply to keep things going. Laughter, on the other hand, is excellent medication if you want to laze around watching reruns of Married With Children.


Dean Somerset is a writer who lives in the United

If a client has a cold, I usually advise them to avoid going to the gym. For one thing, their own exercises may not be very effective, particularly if they are suffering from lung congestion or irritation, and for another, I don’t want to get it! Because the gym isn’t always the cleanest location on the planet, a cold virus may quickly spread across the populace through equipment handling or respiratory droplets in the air.


Spencer Nadolsky, Ph.D.

When my patients have a viral URTI, I don’t mind them performing some mild activity. It helps people feel better, according to anecdotal evidence. There is evidence that individuals who exercise have fewer URTIs. If it’s anything more serious, like influenza (or something similar), I usually advise them to stay hydrated and avoid the exercise. If they have a history of asthma, I make sure they have their rescue inhaler with them if they want to exercise.


Christopher Mohr, Ph.D.

In terms of exercise, I let them “decide” what is best for them based on their current state of health. If you can’t stop coughing or feel like your head is ready to burst, I recommend taking some time off and getting lots of rest, including naps if feasible. For me, a short walk is still preferable to doing nothing — and getting outdoors to do it rather than being trapped on a treadmill going in circles. It’s a little much to try to move iron in the gym.


Cressey, Eric

On a scale of 0 to 10, I usually ask them how terrible it is. A zero means they’re in great shape, while a ten means they’re in the worst shape they’ve ever been in (e.g., violently ill and on their death bed). I’m OK with them training if it’s under a 3 (for example, seasonal allergies), but at a reduced volume and intensity. We could even simply do some mobility training or something similar.

We’re searching for the difference between simply not feeling 100 percent (allergies, stress, headache) and really being ill and infectious, which we don’t want at the gym – for the benefit of that person and others who are exercising around him/her.

Of course, this is very subjective, but I believe it helps us in avoiding days that might otherwise be good training days. Everyone has experienced those sessions when they arrived feeling awful but felt fantastic after the warm-up and went on to have fantastic training sessions. We don’t want to lose out on those chances by staying at home, but we also don’t want to become ill or make anybody else sicker, so it’s a balancing act.


Dr. John Berardi is a neurologist who specializes in the treatment

I usually suggest low-intensity, low-heart-rate “cardio” during the first few days of illness, unless you’re feeling like a train disaster. In general, I prefer 20-30 minute walks outdoors (in the sun) or on a treadmill at home (if you can’t go outside).

You’ll feel better throughout the exercise if you keep the intensity moderate and the heart rate low. You’ll also most likely boost your immune system and hasten your recuperation. Even if you don’t speed up your recuperation, moving will make you feel better.

Cheat sheet for physical activities

When you’re ill, think of these activities.

  • Walking
  • Jogging
  • Swimming
  • Biking
  • Qi gong
  • T’ai Chi
  • Yoga

All of these exercises would be performed at a moderate intensity to keep your heart rate down. They’d also be better if they were done outside in warm weather. If you can’t get outdoors, staying indoors is acceptable.

When you’re ill, stay away from these activities.

  • Strength training at a high intensity
  • Training for endurance
  • Interval exercise at a high intensity
  • Sprinting or high-intensity activities
  • Sports that are played in groups
  • Intense temperatures need extreme exercise.

Stay out of the gym for the sake of the rest of us. You’re far more likely to transmit diseases to others at the gym. Viruses are transmitted via direct touch and inhaling the air of ill individuals.

So, if you’re in the mood for some exercise, go outdoors or to your home gym.

We all appreciate it.

What you ought to do

If you’re in good health and only want to avoid becoming sick:

  • Maintain a modest level of activity on most days of the week.
  • Make sure you receive adequate rest and recuperation time if you engage in high-intensity exercises.
  • Manage your stress levels, get enough of sleep, and wash your hands often.

Allow your symptoms to lead you if you’re already ill.

  • Consider all of the tension you’re dealing with in your daily life (e.g., psychological, environmental, and so forth).
  • Easy activity is likely acceptable as tolerated with a cold/sore throat (no temperature or body aches/pains). You probably don’t want to perform anything strenuous for an extended period of time.
  • Get some rest if you’re suffering from a systemic disease that includes a fever, an increased heart rate, tiredness, vomiting, diarrhea, muscle and joint pain/weakness, and swollen lymph nodes. It may be problematic if you have a severe infection and workout.


To see the information sources mentioned in this article, go here.

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Correspondence between individuals (email). Alwyn Cosgrove is a British actor. The 26th of May, 2014.

Correspondence between individuals (email). Bryan Walsh, ND, on the 26th of May, 2014.

Correspondence between individuals (email). May 29th, 2014, Christopher Mohr, PhD, RD.

Correspondence between individuals (email). Dean Somerset, CEP, CSCS, MSED, CEP, CSCS, MSED, CEP, CSCS, MSED, 27th of May, 2014.

Correspondence between individuals (email). Cressey, Eric. 29th of May, 2014.

Correspondence between individuals (email). Nick Tumminello is a character in the film Nick Tumminello. 3rd of June, 2014.

Correspondence between individuals (email). Dr. Spencer Nadolsky 29th of May, 2014.

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It is common knowledge that exercise is good for you. People in good health often take it for granted, but exercising regularly can improve everything from your cholesterol to your mood. But what if you get sick? Should you be laying down on the couch or running laps at the gym? How about doing both? Should you exercise when you have a cold?. Read more about should you exercise with a low-grade fever and let us know what you think.

Frequently Asked Questions

Is it better to rest or be active when sick?

It is best to rest when you are sick.

Should I exercise while recovering from being sick?

It is best to avoid any strenuous activity while recovering from being sick.

What is the best approach to exercise when you are sick?

The best approach to exercise when you are sick is to find a form of exercise that doesnt exacerbate your symptoms.

Related Tags

This article broadly covered the following related topics:

  • should you exercise when sick
  • should you exercise with a virus
  • exercising with a fever
  • should you exercise with a cough
  • exercise when you have a cold

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