Frank Guerrero works out at Red Dot Fitness Gym, in San Jose, Calif., on June 15, 2021. (Harika Maddala/Bay City News)

Long COVID may age a person’s capacity for exercise by roughly 10 years according to a study published Wednesday by medical researchers in San Francisco.

The study, published in JAMA Network by researchers at the University of California at San Francisco and Zuckerberg San Francisco General Hospital, analyzed data from more than 2,000 participants across 38 pervious studies that tracked exercise performance in people who had been infected with the virus at least three months prior.

That sample was then narrowed to a pool of 359 subjects who had fully recovered from their COVID infection and 464 who had other symptoms of long COVID, including brain fog, fatigue and frequent headaches.

The subjects, who ranged in age from 39 to 56, had their oxygen and carbon dioxide levels monitored while exercising on a treadmill or stationary bike.

According to the researchers, those with long COVID were determined to have an increased likelihood of irregular breathing, a reduced ability to pump blood fast enough through the body and the reduced ability for muscles to extract oxygen from the body’s bloodstream.

The difference in performance between both groups, the researchers said, was roughly 1.4 metabolic equivalent of tasks, a unit that measures energy expenditure during physical tasks.

“This decline in oxygen peak rate would roughly translate to a 40-year-old woman with an expected exercise capacity of 9.5 METs, dropping to 8.1 METs, the approximate expected exercise capacity for a 50-year-old woman,” said Dr. Matthew Durstenfeld of the UCSF Department of Medicine and Zuckerberg San Francisco General Hospital’s Division of Cardiology.

However, the researchers said, more study with a larger sample size was necessary to more-accurately determine how large the effect of long COVID is on exercise capacity.

Dr. Priscilla Hsue, the study’s senior author and a professor at UCSF’s School of Medicine, suggested long-term studies of exercise ability to better understand long COVID’s affect.

“Trials of potential therapies are urgently needed, including studies of rehabilitation to address deconditioning, as well as further investigation into dysfunctional breathing, damage to the nerves that control automatic body functions and the inability to increase the heart rate adequately during exercise,” Hsue said.