Fatigue That Sleep Cannot Fix
This is the symptom most people underestimate and most doctors initially dismiss. Post-COVID fatigue is not tiredness after a long day. It is a cellular-level exhaustion that does not respond to rest. A 2022 study published in Nature Communications found that long-COVID patients showed mitochondrial dysfunction in their muscle cells, the energy-producing machinery was damaged, not depleted. Sleeping eight hours changed nothing because the problem was not a deficit of sleep. It was a deficit of cellular function.
