Sitting idle for long period increases heart failure risk in men, even for those who exercise regularly.
"Be more active and sit less. That's the message here," warned the researchers.
"The study is the first to examine the link between heart failure risk and sedentary time," said Deborah Rohm Young, lead researcher and a senior scientist at Kaiser Permanente in Pasadena, California.
To understand the link, researchers followed a racially diverse group of 84,170 men aged 45 to 69 without heart failure.
Exercise levels were calculated in METs (metabolic equivalent of task) - a measure of the body's energy use - while sedentary levels were measured in hours.
After an average of nearly eight years of follow-up, researchers found that men with low levels of physical activity were 52 percent more likely to develop heart failure than men with high physical activity levels, even after adjusting for differences in sedentary time.
Outside of work, men who spent five or more hours a day sitting were 34 percent more likely to develop heart failure than men who spent no more than two hours a day sitting, regardless of how much they exercised, said the study published in the American Heart Association's journal titled Circulation: Heart Failure.
Heart failure risk more than doubled in men who sat for at least five hours a day and got little exercise compared to men who were very physically active and sat for two hours or less a day.
"People get at least 150 minutes a week of moderate-intensity aerobic activity to reduce their risk for heart failure and other cardiovascular diseases," Young said.
