Understanding Post-COVID Fatigue

Fatigue is the most common symptom of long COVID, but it is rarely a single issue—it is multi-layered. If the strategies from my previous video on The Web of Long COVID have not helped, this video will take a deeper dive into post-COVID fatigue.

The Six Components of Fatigue

Fatigue is not just one problem. It can present in multiple ways, and understanding which components are affecting you is crucial. You may have one, some, or all of these:

1. Loss of Physical Stamina – Before COVID, you could walk two miles without issue; now, even a couple of blocks is exhausting.

2. Muscle Weakness – Lifting something 20 pounds was once easy, but now even five pounds feels difficult.

3. Lack of Mental Stamina – Staying focused on a task becomes a struggle.

4. Daytime Sleepiness – You feel like you could nap at any time, even if you technically have enough energy.

5. Lack of Motivation – Initiating activities feels difficult, even if you can complete them once you start.

6. Post-Exertional Malaise (PEM) – You complete a task but then "pay the price" afterward with exhaustion, making recovery difficult.

Understanding Post-Exertional Malaise (PEM)

PEM is a hallmark of post-COVID fatigue, just as it is in chronic fatigue syndrome (ME/CFS). It is more severe than just feeling tired—it can cause a complete crash. Even a small amount of overexertion can set someone back for weeks.

Why Does PEM Happen?

The main causes of PEM in long COVID:

- Impaired blood circulation – Blood vessels are inflamed, and microclots disrupt oxygen flow.

- Mitochondrial dysfunction – The energy-producing powerhouses of the cells are damaged, leading to energy crashes.

When oxygen and blood flow are limited, mitochondria struggle to produce energy efficiently, leading to delayed fatigue—sometimes occurring 24–48 hours after activity.

Breaking Down the Components of Fatigue

1. Poor Physical Stamina

Fatigue caused by low stamina can stem from several issues:

- Inflammation – COVID triggers cytokines (inflammatory proteins) that cause exhaustion.

- Deconditioning – Many people with long COVID become deconditioned, but some struggle to retrain their bodies.

- Nutrient Deficiencies – Subtle iron, magnesium, and B-vitamin deficiencies can contribute to fatigue.

Other potential causes:

- Orthostatic Intolerance (OI) – Feeling worse when standing versus lying down.

- Shortness of Breath – If breathing issues are present, fatigue won’t improve until oxygen delivery does.

2. Muscle Weakness

- Generalized or localized? If weakness is generalized, it could indicate mitochondrial dysfunction or fibromyalgia.

- Is pain present? Weakness with pain suggests an inflammatory or neurological issue.

- Isolated muscle weakness? If a single muscle group is weak, a neurologist should evaluate for nerve damage.

3. Poor Mental Stamina (Brain Fog)

- Does mental exertion worsen physical fatigue? In long COVID, increased cognitive effort often leads to physical exhaustion—a unique feature of this condition.

- Possible causes:

- Poor blood circulation to the brain

- Sleep deprivation or poor sleep quality

- Medication side effects (e.g., statins, antihistamines, sedatives)

4. Daytime Sleepiness

- Not the same as general fatigue – You may have energy but still feel an urge to nap.

- Possible causes:

- Poor nighttime sleep quality

- Obstructive sleep apnea (snoring is a clue!)

- Medication side effects (e.g., antihistamines)

5. Lack of Motivation

- Common in depression, which is a frequent complication of COVID and the pandemic itself.

- If struggling to initiate activities, monitor mood and thought patterns for negative shifts.

Postural Orthostatic Tachycardia Syndrome (POTS) & Orthostatic Intolerance

Some long COVID patients experience dizziness, fatigue, and increased heart rate when standing—a sign of POTS or orthostatic intolerance (OI).

How to Test for It: The 10-Minute Lean Test

1. Lie down for 5 minutes and measure heart rate & blood pressure.

2. Stand against a wall (without moving) for 10 minutes.

3. Measure heart rate & blood pressure again.

4. If heart rate increases by more than 30 beats per minute (40+ for younger people), you may have POTS.

How to Manage POTS/OI

- Increase salt & fluid intake

- Smaller meals (large meals worsen symptoms)

- Check for mild iron deficiency (common in POTS)

- Support circulation with compression garments

- Consider B1, vitamin D, or melatonin for autonomic support

If symptoms are severe, see a specialist in autonomic dysfunction (often a cardiologist or neurologist).

Shortness of Breath & Fatigue

If breathing issues are causing fatigue, they must be addressed first.

Possible Causes of Post-COVID Shortness of Breath

1. Asthma-like inflammation – COVID can trigger new asthma or worsen preexisting asthma.

2. Pulmonary Fibrosis (Lung Scarring) – Even mild lung scarring (undetectable on X-rays) can lower oxygen levels.

3. Blood Vessel Damage in the Lungs – COVID damages lung capillaries, making oxygen absorption inefficient.

4. Heart Dysfunction (Diastolic Dysfunction) – Post-COVID, some develop heart issues that reduce circulation.

5. Chest Muscle Weakness or Vocal Cord Dysfunction – Weak chest muscles or paradoxical vocal cord movements can contribute to breathlessness.

How to Test for Lung Function Issues

- 6-Minute Walk Test with a pulse oximeter – If oxygen levels drop after walking, lung impairment may be present.

- Echocardiogram – Checks for heart dysfunction if no lung abnormalities are found.

Mitochondrial Dysfunction: The Root of Post-COVID Fatigue

Mitochondria are the energy factories of the body, converting sugar and fat into ATP (energy currency).

How COVID-19 Disrupts Mitochondria

- Viral proteins directly interfere with ATP production.

- COVID blocks fat metabolism, leading to lactic acid buildup and energy crashes.

- Damaged mitochondria fail to regulate immune function, leading to persistent inflammation.

Restoring Mitochondrial Function

A "mitochondrial cocktail" can help support recovery:

- Coenzyme Q10 (CoQ10) – Essential for ATP production.

- Vitamin B3 (Niacin/NAD+) – Critical for mitochondrial repair.

- Carnitine – Helps transport fats into mitochondria for energy.

- Ketone esters – Alternative fuel for mitochondria.

Supporting Mitochondrial Detox

- Probiotic (Vannella) – Converts lactic acid into usable energy.

- Anti-inflammatory diet – Reduces oxidative stress on mitochondria.

- Gentle activity pacing – Avoids triggering PEM.

Final Thoughts: Recovery is Possible

Fatigue recovery in long COVID is a journey, requiring self-management and patience.

Key Takeaways:

- Identify which type of fatigue you have (stamina, muscle weakness, mental exhaustion, etc.).

- Manage POTS and breathing issues first before tackling fatigue.

- Support mitochondria with proper nutrients and pacing.

- Adjust diet & lifestyle to reduce inflammation and oxidative stress.

With the right approach, full recovery is possible.