“Starved for Energy”: Study Sheds Light on Extreme Exhaustion in People with Long COVID

More than 39 million Americans have experienced long COVID: persistent symptoms following the initial infection that can last for months or years. Approximately 15% of adults have had one or more long COVID symptoms, including: impaired smell or taste, breathing problems, brain fog, digestive issues, chest pain, and others. Among the most common signs of long COVID is severe exhaustion, especially after exercise. For sufferers of post-exertional malaise, as it’s officially known, even light physical activity can be debilitating for days or weeks.

A new study may help explain the biological causes of post-exertional malaise. Researchers asked participants to exercise on a stationary bike for about 15 minutes, and collected tissue and blood samples before and after the workout. Comparing the results from people with long COVID to those without long COVID, the scientists discovered stark differences.

For the participants with long COVID, severe damage was found in the mitochondria: the power plant of the body’s cells. As a result, their bodies were starving for energy needed to function. Participants diagnosed with long COVID also showed much more muscle damage than a healthy controls, and this damage also started happening sooner. A closer examination of the long COVID group’s tissue revealed a high amount of cell death and an accumulation of microclots. The study built on results from previous studies, which showed that long COVID patients’ skeletal muscles struggled to absorb oxygen from the blood. The new study confirmed that for people with long COVID, the immune system went into overdrive, leading to inflammation and muscle death.

Full Story: NPR, Nature