Study author Larsen also stressed that the study could only point to an association between sitting and pericardial fat, it could not prove a cause-and-effect relationship.
Dr. Sripal Bangalore, an assistant professor of medicine at NYU School of Medicine in New York City, added that the study may help unravel the mystery of why a "couch potato" lifestyle is so unhealthy.
"The current study shows that a sedentary lifestyle may have a differential increase in fat accumulation based on activity level," he said. "It is very intriguing and should be confirmed in future studies," Bangalore added.
"I guess until that time, it is time to sit less and be more active," said Bangalore, who is also director of research at the Cardiovascular Outcomes Group at NYU Langone Medical Center.
Findings presented at medical meetings are typically considered preliminary until published in a peer-reviewed journal.
There's more on physical activity and the heart at the American Heart Association.
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