Strenuous exercise can lead to flare of long COVID symptoms

Doctor typing on computer

Hello, dear readers, and welcome to a bonus letters column. We're continuing with mail from readers living with long COVID, and for whom recent research is offering some insights.

The latest health data from the Centers for Disease Control and Prevention show that at least 20% of people who contracted COVID-19 have gone on to develop the group of lingering symptoms known as long COVID. The condition occurs more often in women than in men, and it is less common in older populations. The data show that long COVID occurs three times as often in adults ranging in age from 50 to 59 as in those who are 80 and older.

-- Long COVID is often marked by persistent fatigue and a loss of stamina. Several readers have asked if exercise in itself might be a useful therapy. "Could it be a question of powering through to regain strength and endurance, like you do in rehab?" a reader asked. Unfortunately, newer research suggests that the answer is no. It turns out that strenuous exercise often leads to a flare of long COVID symptoms. This phenomenon has earned the name “post-exertional malaise.”

In a new study, researchers looked at whether oxygen deficit plays a role in post-exertional malaise. They found that although oxygen was successfully transferred from the lungs to the bloodstream, the tissues of the bodies of long COVID patients were unable to access and use it. Another study hints at the reason why: Researchers found that in long COVID patients with exercise intolerance, mitochondria behaved abnormally. Mitochondria are cellular structures that use oxygen to generate a molecule known as ATP, which the muscles use for energy. These are surprising developments. They expand our understanding of long COVID and open new avenues of inquiry that may point to effective treatment.

-- A reader had a question regarding an older column in which we wrote about hyperbaric oxygen therapy. At the time, it had been introduced as a possible treatment for some of the symptoms of long COVID. "Is there any news about whether HBOT works to help long COVID?" they asked. "Can I get it if my doctor says it's OK?" Hyperbaric oxygen therapy, or HBOT, involves breathing pure oxygen while in a pressurized chamber. Commonly used for decompression sickness, carbon monoxide poisoning, and wound and burn care, the treatment makes higher concentrations of oxygen available to the tissues. Recent research continues to suggest that HBOT may ease brain fog and improve cardiac function in some people with long COVID. However, the studies thus far have been quite small, and more research is needed.

At this time, HBOT is not approved by the FDA for treatment of long COVID. As a result, it is not covered by insurance for this purpose. Payment for the treatment, which can be quite pricey, would be out of pocket. If you and your doctor decide to move forward with HBOT, they will write you a recommendation. It is important to receive HBOT at a hospital or other accredited facility.

(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)

Take the Next Step

Learn more about the UCLA Long COVID Program and how post-COVID symptoms are treated.