Car owners with a television are 27 per cent more likely to suffer heart attacks than people who have neither, according to a global study on physical exercise and heart disease published yesterday.

More broadly, the study – covering more than 29,000 people in 52 countries – showed that working up a light sweat may be the best preventative medicine against heart failure.

Until now, surprisingly little research has focused on how physical exertion at work and play influences the incidence of heart attacks, and even less has directly compared this data across nations at all income levels.

“This study shows that mild to moderate physical activity at work, and any level of activity during leisure time, reduces the risk of heart attacks,” said lead researcher Claes Held, a professor at Uppsala University in Sweden.

It also “extends previous findings of the protective effect of leisure-time physical activity ... to low- and middle-income countries”.

Held and colleagues poured over data collected from 1999 to 2003 for the so-called Interheart study.

They compared one group of more than 10,000 middle-aged men and women who had had a single heart attack with an even larger cohort with no history of cardiovascular disease.

Physical activity at work and during leisure time was divided into four levels of exertion: being completely sedentary at one extreme, and, at the other, doing hard physical labour on the job or heart-pounding aerobic exercise while at play.

Not surprisingly, the study, published in the European Heart Journal, found that exercise is good for the heart.

But the effectiveness of physical activity varied depending on the setting and intensity, according to the research.

Any kind of workout during leisure time was shown to be a plus, with heart attack risk – compared to doing almost nothing – dropping 13 per cent for mild activity and 24 per cent for moderate or strenuous exercise.