Fatigue is a common symptom of viral infection, and having fatigue with a COVID-19 infection is no exception. But the severity and longevity of that fatigue is what sets COVID-19 apart from the common cold or even the flu. You might…
For most patients with COVID-19, this feeling disappears after two or three weeks. But if you’re still experiencing fatigue weeks or months after your initial infection, you may have long COVID.
Post-viral fatigue is one of the most common symptoms experienced by COVID long haulers, with nearly half reporting this long-term symptom for weeks or months after their original infection.
Patients describe this fatigue as more than feeling physically tired after a session at the gym. It comes with an array of other symptoms, like aches and pains in the body, headaches, sleep problems, and brain fog.
Scientists don’t yet know why so many post-COVID-19 patients experience persistent fatigue. It may result from an overreaction of the body’s immune system, breathing issues caused by the virus, disruption of the autonomic nervous system, and more. There’s even a clinical trial in the UK currently testing the idea that the virus affects the way cells in our body produce energy through cellular organelles called mitochondria.
In this article, we’ll look at:
Our treatment program is designed to help post-concussion patients recover from persistent symptoms. After just one week of treatment, 95% of our patients show statistically verified improvement in brain function. Thus far, we’ve seen similar results with long COVID patients who pass our current screening criteria. To discuss your specific symptoms of COVID-19 and determine whether you’re eligible for treatment at our clinic, schedule a consultation.
Note: Any data relating to brain function mentioned in this post is from our first generation fNCI scans. Gen 1 scans compared activation in various regions of the brain with a control database of healthy brains. Our clinic is now rolling out second-generation fNCI which looks both at the activation of individual brain regions and at the connections between brain regions. Results are interpreted and reported differently for Gen 2 than for Gen 1; reports will not look the same if you come into the clinic for treatment.
Many COVID long haulers experience a debilitating array of symptoms, including breathlessness, muscle pain, and a persistent cough. Fatigue is another symptom to add to the list.
Every patient describes post-COVID fatigue a little differently. Some say they feel exhausted, lacking in energy, weak, unable to motivate themselves, or sleepy. For others, it’s more about what fatigue does to them, such as causing problems with short-term memory, irritability, or dizziness.
Some patients feel tired all the time, while for others, it comes after a short period of intense activity, such as work or exercise. For some, this feeling of fatigue fluctuates: Some days, patients feel great and manage to engage in their daily activities. Other days, they feel incapacitated with debilitating symptoms.
All patients agree that it’s not like normal tiredness after a day’s work or physical exercise. Fatigue caused by long COVID has physical components, including low energy and feeling sleepy, as well cognitive components, like brain fog or poor concentration.
Post-COVID fatigue (sometimes diagnosed as chronic fatigue syndrome) doesn’t go away after a good night's sleep. It’s like patients can’t fully recharge their battery during the night and wake up without the energy they need to get through the day. Inevitably, they reach a point when the battery is empty and they have to rest until they recharge a bit.
Symptoms of Post-COVID-19 fatigue include physical, cognitive, and behavioral complications, such as:
If you find that your symptoms are worsening rapidly, seek medical assistance immediately.
Despite growing interest from the scientific community regarding long COVID and its long-term effects, there is no definitive answer to what causes post-COVID fatigue. At this stage, researchers can’t say with complete certainty which factors are at work in long haulers, but some of the most likely explanations for post-COVID fatigue include some combination of the following:
Many long-haul COVID-19 patients experience breathing issues months after their initial diagnosis.
It’s not difficult to see how this can cause fatigue: Breathing problems reduce the amount of oxygen circulating in the body. When your oxygen levels are low, you feel tired.
This sets up a dangerous cycle. If you feel tired and lethargic because of low oxygen levels, you’re less likely to engage in physical activity. If you don’t exercise, you may lose stamina and tire more easily.
Researchers are not entirely sure what’s causing these breathing problems in the first place, but the good news is that we know how to treat them in most post-COVID patients. Read more details about our treatment program later in the article.
Fatigue after a coronavirus infection can also result from vascular changes in the brain.
In a healthy brain, nerve cells receive energy and oxygen from the blood vessels surrounding them. This connection is called neurovascular coupling (NVC).
COVID-19 disrupts the flow of oxygen and nutrients within the brain by disrupting the communication between neurons and blood vessels. As a consequence, parts of the brain function worse than they should. This is known as neurovascular coupling (NVC) dysfunction.
Depending on which areas of the brain are affected, this could cause different symptoms. For example, there’s an area in the brain called the Ascending Reticular Activating System (ARAS), which is responsible for the transition between being asleep and awake. It’s not been tested in patients with long COVID, but researchers believe that if this area is affected, it may lead to persistent fatigue.
No matter which brain regions are affected, you can feel fatigue just from the extra work the brain needs to do to manage regular, everyday activities.
A third possible explanation of fatigue in long haulers involves disruption of the autonomic nervous system (ANS).
The ANS is part of the nervous system and controls our body’s internal organs without us even noticing. It influences muscles and organs throughout the body and controls a range of functions such as heart rate, breathing, and digestion.
The ANS has multiple parts. Two of the most important are the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
When our brain suspects there’s a threat, it activates the SNS, which in turn starts pumping blood to muscles and increases breathing rate. The aim is to make you ready to fight for your life, and this is why it’s called the “fight or flight” mode. When the threat is gone, the PNS kicks in and calms everything down. This is often called the “rest and digest” mode.
In healthy individuals, the SNS and PNS are in a constant state of flux, with each system making small adjustments throughout the day. In long COVID patients, however, there is evidence to suggest the sympathetic nervous system becomes dominant. Not surprisingly, staying in this constant mode of physically heightened alert resultsin physical, mental, and emotional exhaustion.
You can read more about how this works and the symptoms it causes in our article about autonomic nervous system dysfunction in post-concussion patients.
Many patients suffering from long COVID also experience gastrointestinal (GI) issues. The GI system is responsible for absorbing nutrients into the body. If it does not absorb enough nutrients — carbohydrates, protein, fats, vitamins, and minerals — patients’ energy levels decrease.
At Cognitive FX, we assess all of our patients for GI problems. If patients come to us with serious GI issues — such as losing a lot of weight and failing to put it back on — we recommend that they visit a gastroenterologist to address their GI function before starting treatment with Cognitive FX.
Our treatment is designed to address major issues in the brain. Patients with unrelated GI problems may not feel better right after treatment because their brain would still be starved of nutrients.
Post-COVID fatigue may also have something to do with the body’s immune system.
When you’re fighting a virus, the immune system produces chemicals called cytokines, which are responsible for many of the symptoms of viral infection, such as fatigue, aches, and pains.
Under normal circumstances, the production of cytokines stops once the viral infection is gone. Yet there are indications that, in some long COVID patients, the levels of cytokines never return to normal. This overactive response may cause persistent fatigue.
Some scientists think that dysfunctional mitochondria may cause post-COVID fatigue.
Mitochondria play a vital role in transforming the energy from your diet (carbohydrates and fat) into a type of energy that can be used by your cells. This is called adenosine triphosphate (ATP). Supplies of ATP don’t last long, so the cells need to produce it constantly.
It seems that Sars-CoV-2 can disrupt mitochondria’s normal operations, which in turn affects the production of energy in your body. To corroborate this idea, long haulers accumulate lactic acid in their muscles, which indicates that mitochondria are not fully operational.
To address this issue, a team of researchers in the UK is currently coordinating a clinical trial to test a new drug targeting mitochondria. The aim is to improve exercise tolerance and reduce fatigue in 40 patients with long COVID. Results are expected in mid-2022.
Long haulers may also experience fatigue as a consequence of other symptoms, including poor sleep quality, for example. This is known as secondary fatigue.
Everyone's experienced fatigue and lack of focus after a poor night's sleep. An occasional night without sleep makes you feel tired the next day, but it won't cause any health issues in the long term. For long haulers, however, the constant struggle to sleep well can lead to brain fog, difficulties concentrating, and/or persistent fatigue.
Common post-COVID symptoms such as headaches, exercise intolerance, and vision problems can lead to feeling fatigued as well.
Our treatment program is designed to help post-concussion patients recover from persistent symptoms. After just one week of treatment, 95% of our patients show statistically verified improvement in brain function. Thus far, we’ve seen similar results with long COVID patients who pass our current screening criteria. To discuss your specific symptoms of COVID-19 and determine whether you’re eligible for treatment at our clinic, schedule a consultation.
During the acute phase of the coronavirus disease, mild fatigue is a normal response. For most people, this fatigue resolves after two to three weeks. Don’t try to increase your activity levels too soon; rushing your recovery can make you feel tired for longer.
Nobody really knows how long COVID-19 fatigue will last for long haulers. A recent study of over 1200 long haulers found that over half the patients complained of fatigue six months after their infection, and one in five still suffered from it 12 months later.
In addition, the severity and length of time that patients experience fatigue are not related to the severity of the initial infection. Patients can be unwell during acute COVID-19 but then recover quickly, while others with a mild case may go on to develop fatigue for a long time afterward.
The good news is that patients have options when it comes to treatment of post-COVID fatigue.
For most long haulers, fatigue is one of their many symptoms. Long COVID can affect every organ in the body, causing difficulties from shortness of breath and trouble sleeping to erectile dysfunction and heart palpitations.
Instead of treating each symptom separately, we approach long COVID as a whole.
Soon after long COVID appeared, we realized this condition impacts the brain in a similar way to post-concussion syndrome (PCS), the primary condition we treat at our clinic. PCS occurs when concussion symptoms fail to resolve months after a head injury. Some of our patients have spent decades suffering from headaches, dizziness, brain fog, and more before finding our clinic.
Note: While concussions are the most common cause of post-concussion syndrome, blunt trauma is not the only way to injure your brain. We’ve treated patients who injured their brains via carbon monoxide poisoning, encephalitis from an infection, transient ischemic stroke, and more. In this sense, COVID-19 is no different in that it causes brain dysfunction.
After confirming our suspicions of the similarity between long COVID and post-concussion syndrome via neuroimaging, we adapted our treatment protocols for COVID long haulers.
The aim of treatment is to help you feel better by restoring normal neurovascular coupling throughout the brain and helping the autonomic nervous system re-regulate. Before treatment starts, each patient undergoes a brain scan called functional neurocognitive imaging (fNCI) to detect what areas of the brain are functioning normally and what parts were affected by the COVID-19 illness.
We use these results to design a customized treatment plan combining a series of cardio exercises and other therapies, including cognitive, sensorimotor, neuromuscular, and vision therapies, to name just a few.
In practical terms, our EPIC treatment — short for Enhanced Performance in Cognition — consists of evaluation (including looking at breathing, ANS dynamics, vestibular function, and more conditions that wouldn’t show up on a brain scan), heavy therapy, and reassessment and planning.
The idea of intensive treatment can be off-putting when you suffer from severe fatigue. But all of our long COVID patients have been able to complete treatment.
That’s because we follow a three-step process designed to help the brain cope with increased demands during your week with us.
We follow a prepare/activate/rest pattern:
Patients repeat this sequence throughout the week(s) to restore healthy neurovascular coupling in the brain and reduce the incidence and severity of long COVID-19 symptoms, including fatigue. Most patients start feeling the benefits even before the treatment ends, and a second fNCI scan confirms these improvements.
After treatment, our therapists meet with each patient to discuss exercises to do at home while recovery continues.
To determine if you’re eligible for treatment at our clinic, schedule a consultation.
So what can you do if you're suffering from post-COVID fatigue? There is no medication available specifically for fatigue, but there are many things you can do to ease your symptoms, aid your recovery, and improve quality of life.
Our treatment program is designed to help post-concussion patients recover from persistent symptoms. After just one week of treatment, 95% of our patients show statistically verified improvement in brain function. Thus far, we’ve seen similar results with long COVID patients who pass our current screening criteria. To discuss your specific symptoms of COVID-19 and determine whether you’re eligible for treatment at our clinic, schedule a consultation.
