A recent study reveals that individuals grappling with long Covid may encounter fatigue and pain following extended periods of exercise, attributing these challenges to underlying biological changes in the body. This noteworthy discovery emerges amid a surge in cases of the JN.1 subvariant of Omicron across the United States.
According to experts, long Covid can lead to severe muscle damage, mitochondrial issues, and the formation of microclots within the body, posing hurdles for those engaging in regular physical activity. Dr. Rob Wust, the study’s author from Vrije Universiteit (Free University) Amsterdam, emphasizes, “It’s really confirming that there is something inside the body going wrong with the disease.”
The U.S. Department of Health and Human Services estimates that anywhere from 7.7 million to 23 million Americans have encountered long Covid at some point during the pandemic, with many reporting worsening symptoms post-exercise.
Wust’s study, published in the journal Nature Communications, involved 25 long Covid patients experiencing exercise-related issues and 21 individuals who had fully recovered from long Covid. All participants were previously healthy and fit, catching the virus while of working age.
During the study, each participant spent approximately 15 minutes on an exercise bike, with blood samples and skeletal muscle biopsies collected before and after the activity. On average, individuals with long Covid exhibited lower exercise capacity compared to healthy participants. The study unveiled a higher proportion of white fibers in the muscles of long Covid patients, containing fewer power-producing structures called mitochondria.
Wust suggests that this may elucidate the reduced exercise capacity observed in those with long Covid. Additionally, the study identified increased clumps of a protein called amyloid in the skeletal muscles of long Covid patients, although there was no evidence indicating that these “microclots” were obstructing blood vessels.
Furthermore, participants with long Covid displayed heightened tissue damage post-exercise, coupled with signs of the body attempting to initiate repairs. Wust notes, “That can explain, for instance, the muscle pain that these patients are experiencing after exercise.”
Given these findings, Wust advises individuals with long Covid to refrain from intense exercise, emphasizing its potential to exacerbate muscle damage, worsen metabolism, and contribute to prolonged muscle pain and fatigue.
The study suggests that treatments focusing on improving mitochondrial health could offer benefits for individuals grappling with long Covid.