WEDNESDAY, Jan. 11 (HealthDay News) -- People who own a car and a television tend to be at increased risk for heart attack, a new study finds.

On the other hand, people in developed and developing countries who are physically active during work and leisure time have a significantly lower risk of heart attack, the researchers found.

The findings come from an analysis of data from more than 29,000 people in 52 countries in Africa, Asia, Australia, North and South America, Europe and the Middle East. The study was published online Jan. 11 in the European Heart Journal.

"Until now, few studies have looked at the different aspects of physical activity both at work and during leisure time in relation to the risk of heart attacks," first author Dr. Claes Held, an associate professor at Uppsala Clinical Research Center and the cardiology department at Uppsala University Hospital in Sweden, said in a journal news release.

"Much is already known about the association between physical activity and cardiovascular risk, but what this study adds, among many other things, is a global perspective. The study shows that mild to moderate physical activity at work, and any level of physical activity during leisure time reduces the risk of heart attack, independent of other traditional risk factors in men and women of all ages, in most regions of the world and in countries with low, middle or high income levels. Interestingly, heavy physical labor at work did not protect against heart attacks," Held said.

The data analysis revealed that people who did light or moderate physical activity at work had a 22 percent and 11 percent lower risk of heart attack, respectively, than those who did little physical activity at work. However, heavy physical labor did not reduce heart attack risk.

Compared to those who did little physical activity during leisure time, the risk of heart attack was 13 percent lower for people who did mild physical activity and 24 percent lower for those who did moderate or strenuous activity during leisure time.

People who owned both a car and TV had a 27 percent higher risk of heart attack than those who owned neither a car nor TV.

A higher percentage of people in low-income nations had sedentary jobs and did less physical activity in their leisure time, compared to those in middle- and high-income countries, the researchers noted.

"These differences in PA [physical activity] were most pronounced regarding leisure-time activity," they wrote. "This may partly be explained by differences in education and other socio-economic factors. In addition, this may also reflect differences in culture and in climate." It's less likely that an individual will performing leisure-time physical activity in tropical or hot climate zones than in more temperate areas of the world, they added.

All people should be encouraged to get daily moderate exercise in order to prevent heart disease, the researchers concluded.

"The data have some real-life implications," Held said. One suggestion could be getting lower-income countries more involved in promoting physical activity as their societies start to use more labor-saving devices, he said.

More information

The U.S. National Heart, Lung, and Blood Institute offers a guide to physical activity.