New York, March 7 (IANS): Sitting for long hours everyday is associated with increased coronary artery calcification that can increase the risk of a heart attack, new research says.

The results suggest that exercise may not entirely counteract the negative effects of a mostly sedentary lifestyle on coronary artery calcium. "It's clear that exercise is important to reduce your cardiovascular risk and improve your fitness level," said study's lead author Jacquelyn Kulinski.

"But this study suggests that reducing how much you sit every day may represent a more novel, companion strategy (in addition to exercise) to help reduce your cardiovascular risk," Kulinski, an assistant professor of cardiovascular medicine at the Medical College of Wisconsin, US, added.

This study offers a unique perspective on the effects of sedentary behaviour because it links sitting with an early marker for heart disease risk.

Coronary artery calcification, measured through a non-invasive CT heart scan, indicates the amount of calcium contained in plaques within the heart's arteries.

Analysing heart scans and physical activity records of more than 2,000 adults living in Dallas, the researchers found each hour of sedentary time per day on average was associated with a 14 percent increase in coronary artery calcification burden.

The association was independent of exercise activity and other traditional heart disease risk factors.

"I think the study offers a promising message. Reducing the amount of time you sit by even an hour or two a day could have a significant and positive impact on your future cardiovascular health," said Kulinski.

The research is scheduled for presentation at the American College of Cardiology's 64th Annual Scientific Session from March 14 to16 in San Diego.