At least 65 million people around the world have long COVID, a condition where they continue to experience COVID-19 symptoms for months after their symptoms originally start.
The most common symptoms of long COVID are fatigue, dizziness, mobility issues, sleep problems, cognitive impairment, and brain fog or inability to concentrate.
Prof. Michèle van Vugt, professor of internal medicine at the Amsterdam University Medical Center and co-lead author of this study, told Medical News Today she and her colleagues decided to look for a physical cause of the tiredness experienced by people with long COVID because of the impact it has on their lives.
For this study, Prof. van Vugt and her team recruited 25 people with long COVID and 21 healthy control participants. They were all asked to take a cycling test for approximately 15 minutes, that was designed to push them to maximum exertion.
According to researchers, the cycling test caused a worsening of symptoms in the participants with long COVID, known as post-exertional malaise (PEM), resulting in worsening of fatigue for up to 7 days after.
Scientists examined blood and muscle tissue samples from all participants both one week before the cycling test and one day after.
They found various abnormalities in the muscle tissue of the participants with long COVID, including lowered functioning of the mitochondria of the muscle. Known as the “powerhouse of the cell,” mitochondria are responsible for making the energy needed to power the body’s cells.
“So, the cause of the fatigue is really biological,” Prof. van Vugt explained. “The brain needs energy to think. Muscles need energy to move. This discovery means we can now start to research an appropriate treatment for those with long COVID.”
https://www.medicalnewstoday.com/articles/long-covid-fatigue-linked-to-malfunctioning-mitochondria
(Tom: To learn how to improve your mitochondrial function, watch this interview with a brilliant human biologist: https://www.dailymotion.com/video/x8phud1)