COVID-19 and Fatigue: Link, Feeling, Treatments

Fatigue is one of the most common symptoms experienced by people with long COVID, with some research showing 85% of participants with long COVID reporting fatigue.

Why Fatigue Is a Long COVID Symptom

SARS-CoV-2 (the virus that causes COVID-19) triggers the production of IFN-y (an antiviral protein). This is associated with fatigue, muscle aches, and depression. A 2024 study found that while for most people, production of this protein stops once the virus has cleared, for some people with long COVID, IFN-y production continues until symptoms improve (up to 31 months in this study).

An analysis performed through the University of Alberta in Canada found that the 30 people with long COVID showed persistent metabolomic abnormalities 12 months after their illness with acute COVID-19, such as:

• Abnormally low levels of the cellular source of energy adenosine triphosphate (ATP), likely resulting from mitochondrial dysfunction caused by COVID-19 (lowers energy levels and may help explain fatigue with long COVID)
• Signs of chronic, systemic inflammation (including markers of compromised gut integrity, which can result in gut products leaking into the blood)
• Significantly lower-than-normal plasma levels of the amino acids sarcosine, glutamine, and serine (these amino acids are associated with normal brain function, and people with long COVID who had lower plasma levels of these were more likely to report symptoms of anxiety, clinical depression, and mental impairment)

Describing COVID Fatigue

The Centers for Disease Control and Prevention (CDC) defines long COVID as:

• Symptoms continuing after the initial infection has resolved, and lasting longer than 12 weeks
• Symptoms returning sometime after the initial infection has resolved, then continuing for longer than 12 weeks
• Symptoms appearing sometimes after the initial infection has resolved, and lasting longer than 12 weeks, even though no symptoms were present during the acute illness

Fatigue is one of the most common symptoms of long COVID. Post-COVID fatigue is more than feeling tired. It is multifaceted and complex and can involve the following:

• Persistent feelings of tiredness, often to the point of exhaustion, that do not improve after rest or a few night’s good sleep
• Brain fog (difficulties with concentrating, focusing, and memory, feeling mentally sluggish or fuzzy)
• Physical weakness and problems with muscles, such as muscle weakness, muscle aches and pains, and impaired motor coordination
• Reduced or lack of energy to do everyday tasks
• Feeling overwhelmed when faced with having to do things
• Feeling achy
• Feeling worn out after activities you didn’t previously find tiring, such as doing the dishes or climbing stairs
• Finding a busy day more exhausting than you did before
• Becoming out of breath when doing simple activities
• Feeling “weighed down”
• Having a loss of interest in doing activities
• Difficulty following instructions, multitasking, making decisions or plans, or putting thoughts into words
• Symptoms of mental health changes, such as those associated with depression or anxiety
• Sleep problems (too much or too little), and not feeling rested after sleeping

Factors That Exacerbate Fatigue After COVID

Factors that have been associated with an increased risk of long COVID and/or post-COVID fatigue include:

• Sex: It occurs more commonly in women.
• Ethnicity: People who are Hispanic or Latino have a higher risk.
• Severity of the initial illness: Having severe COVID-19 illness, being hospitalized, and needing intensive care increase risks.
• Age: It’s more common in people who are aged 65 and older.
• Comorbidities: Having other health conditions, such as hypertension or mood disorders, can increase the risk.
• Vaccination status: People who did not get a COVID-19 vaccine are at an increased risk.
• Health inequalities: Inequalities associated with disability, economics, geography, and other social factors can increase the risk of negative health impacts and outcomes from long COVID.

Symptoms of long COVID and post-COVID fatigue can be exacerbated by factors such as:

• Pushing through symptoms, instead of resting when your body tells you to
• Post-exertional malaise (when symptoms seem to get worse after any physical or mental effort)
• Lack of restful sleep

Treatment for COVID Fatigue

Preventing COVID infection is currently the best way to prevent long COVID. While strict protocols for COVID are no longer in effect, it is important to continue to exercise prevention strategies, such as:

Getting COVID-19 vaccines may also reduce the risk of long COVID by up to 30% in those vaccinated before infection. More research is being conducted exploring the potential for COVID-19 vaccination to reduce the severity of long COVID symptoms.

Research on how best to treat long COVID is ongoing as the condition is new. Currently, the medical community recommends measures that have been shown to help conditions that cause similar symptoms, such as ME/CFS, Parkinson’s disease, concussion, stroke, and brain injury.

One area of research suggests a transcutaneous electrical nerve stimulation (TENS) machine may be used in treating fatigue associated with long COVID, but more research is needed.

Research also suggests that post-COVID fatigue symptoms can improve over time, with varying rates of symptom duration.

Some specialists that may help address symptoms of long COVID or help you find resources include:

• Cognitive behavioral therapists
• Neurologists
• Neuropsychologists
• Nutritionists/dietitians
• Occupational therapists
• Physiotherapists
• Psychiatrists
• Social workers

Managing Fatigue

Energy conservation is important with chronic fatigue. Energy works like a battery: It can run out with use and needs to be recharged. To help with using energy efficiently, try the four Ps:

Plan:

• Look at how you plan your activities.
• Use a diary, calendar, or planner to ensure you are taking on a reasonable amount of activities in a day.
• Plan to alternate heavy and light tasks.
• Break up tasks into steps.
• When possible, try to prepare or complete some components of tasks ahead of time.
• Keep items you need near where they are needed and ensure they are easy to reach.
• Have duplicates of items in several areas of the house to avoid having to go get them through the day.
• Use a bag to carry multiple items instead of making multiple trips.
• Take items with you when you need to go up the stairs instead of making a special trip.
• Think of energy like money: You need to budget it to make sure it covers what it needs to, and doesn’t run out unexpectedly.
• Make lists.
• Schedule breaks into your plans, and take them whether you feel you need them or not.
• Notice when you seem to have more energy, when you seem to need more of a break, and plan accordingly

Pace:

• Go slow and steady (doing things slowly requires less energy and oxygen).
• Practice breathing exercises while doing tasks.
• Breathe out when doing a strenuous part of an activity, or when bending or reaching.
• Take frequent, short rests, even if you feel like pushing through.
• Don’t allow yourself to hit a wall before taking a break.

Prioritize:

• Sort tasks into “essential” and “desirable” and also “energy-draining” vs. “energy-boosting.”
• Try to balance between things you need to do and things you want to do.
• Aim for at least one “desirable” and one “energy-boosting” task each day.
• Set boundaries and say no when wanted or needed.
• Ask for help and accept help that is offered.
• Examine expectations (from yourself and others) and see if there needs to be an adjustment.

Position:

• Be aware of your position while doing activities.
• Sit down while doing tasks as often as you can.
• Support your elbows and forearms when doing tasks with your arms that take longer than a few minutes.
• Keep items at waist height and where they will be used, to avoid stooping and stretching.
• Use long-handled tools when available.
• Use assistive devices if they benefit you, such as shower chairs, mobility aids, and tools to help with dressing.

It is also important to look after your overall health:

• Talk to your healthcare provider about what exercise or movement activities may be appropriate for you.
• Eat nutritious foods (try to look for premade, nutritious meals if cooking is too difficult).
• Practice good sleep hygiene (taking measure to promote restful sleep, such as routine, relaxation, and sleep environment), and get assessed for sleep disorders.
• Talk to your employer about accommodations that can be made to help you manage your symptoms, such as flexible work hours or working from home.
• Socialize and spend time with people who boost your energy, in ways you can manage.

Managing Brain Fog

The four Ps are helpful when managing brain fog as well. In addition to this strategy, you can also try:

• Pay attention to your sleep and mood.
• Give yourself downtime when you need it.
• Avoid substance use, including alcohol.
• Remember it is normal to have cognitive slips sometimes, and that everyone recovers at their own pace.
• Use organization tools such as planners, reminders and alarms on devices, calendars, etc.
• Break difficult tasks into smaller steps (write down each step).
• Keep your environment neat and tidy.
• Keep important items (keys, wallet, etc.) in the same place so they are easy to find.
• Reduce distractions when you need to concentrate.
• Avoid multitasking.
• Take on challenging tasks when you are feeling most alert.
• Ask for help.

When to See a Healthcare Provider

Fatigue and brain fog can be symptoms of conditions other than long COVID. It is important to see your healthcare provider if you are experiencing symptoms of fatigue or brain fog, whether or not you have recently had a COVID-19 infection. This is especially important if there are factors such as:

• Symptoms that are getting worse
• Symptoms that are interfering with your ability to function normally
• Additional symptoms, such as fever, weight loss, unusual bleeding or bruising, pain, or night sweats

Summary

Fatigue is one of the most common symptoms of long COVID.

Fatigue associated with long COVID has symptoms that can impair daily functioning, such as exhaustion, muscle weakness and aches, and brain fog.

There is no specific recommended treatment for post-COVID fatigue, but symptoms can be managed with techniques such as the four Ps, and with prioritizing rest and energy conservation.