Your trusted source

People suffering from post-COVID have been discouraged from exercising because early observations suggested it could be harmful. In a study published in JAMA Network Open, researchers from Karolinska Institutet show that post-COVIDdoes not mean that exercise must be strictly avoided, the medical university reported.

People affected by post-COVID often experience symptoms such as extreme fatigue, shortness of breath, high resting heart rate, and muscle weakness. Symptoms are often exacerbated by exertion.

“The World Health Organization (WHO) and other major bodies have said that people with post-covid should avoid intense exercise,” says Andrea Tryfonos, a researcher at the Department of Laboratory Medicine, Karolinska Institutet, and first author of the current study.

But now she and a research team can show that this recommendation is probably too strict.

The researchers recruited 31 patients with post-covid but no other diagnoses. For comparison, 31 sex- and age-matched people without post-COVID were selected. All participants then completed three different training sessions consisting of high-intensity interval training, moderate-intensity continuous training and strength training in a randomized order a few weeks apart.

The participants were checked before, immediately after and two days after the training sessions for symptom levels. In addition, they underwent several medical examinations, including blood tests, heart ultrasound, spirometry for lung function, muscle strength tests, neurophysiological tests, and muscle biopsies.

The study also showed that there are some differences between the people with post-covid and the controls.

“People with post-COVID had generally lower levels of fitness and muscle strength, which could be due to both the infection and lower activity. After two years of prolonged symptoms and being discouraged from exercising, it's not surprising that you have lost some of your work capacity," says Andrea Tryfonos.

The researchers also found that as many as 62 percent of people with post-COVID suffered from myopathy, a change in the muscle tissue that impairs muscle capacity.

“This percentage is far too high to be explained by reduced activity alone. Therefore, we are currently analyzing the biopsies to see if we can explain the reason behind these muscle changes," she says.

However, she believes that the recommendations for exercise in post-COVID should be revised now.

The research was funded by Center for Innovative Medicine, CIMED, 2022-24, Tornspiran Foundation, Magnus Bergvalls Foundation, Lars Hierta Minne Foundation, Åke Wiberg Foundation.