Sitting at home or at work

Which is worse for heart health?

New research has found that not all forms of sedentariness are equal when it comes to the extent to which they put heart health at risk. Sitting on the couch, watching TV could increase heart risk more than sitting at a desk doing office work, report agencies.

We already know that a sedentary lifestyle, in which a person sits down for long periods every day and gets little exercise, is bad for health in general and heart health in particular.

However, in a new study, researchers from the Vagelos College of Physicians and Surgeons at Columbia University in New York City, NY, have found that there is a difference between occupational sitting (sitting at work) and leisure time sitting (sitting at home, watching TV).

The researchers worked specifically with a cohort of African American people, aiming to fill a gap in the research to date, which has primarily focused on white Europeans. Nevertheless, they believe that despite the specificity of the study cohort, the findings could apply to everyone, regardless of ethnicity.

And, the investigation revealed a — perhaps surprising — distinction: The time that a person spends sitting on the couch at home, watching TV, is much more likely to increase their risk of heart problems than the time they spend sitting at work.

"Our findings show that how you spend your time outside of work may matter more when it comes to heart health," explains study author Keith Diaz, Ph.D.

The solution to this problem may be to spend more time being not just active, but intensely active, the researcher notes.

"Even if you have a job that requires you to sit for long periods of time, replacing the time you spend sitting at home with strenuous exercise could reduce your risk of heart disease and death," says Diaz.

Diaz and team explain their findings and suggest a possible explanation for these results in a study paper that appeared yesterday in the Journal of the American Heart Association. 

Chilling on the couch raises risk by half The researchers analyzed data for a cohort of 3,592 participants who had enrolled in the Jackson Heart Study, a community-based study focused on the causes of cardiovascular, renal, and respiratory diseases among African Americans. All of the participants lived in Jackson, MS, and the health and lifestyle data available about them covered a period of 8.5 years. The information included how much time the participants spent sitting at work, as well as how much time they spent watching TV versus exercising in their spare time.

Diaz and team found that people who reported sitting and watching TV for 4 or more hours each day had a 50% higher risk of cardiovascular problems and premature death compared with individuals who sat in front of the television for 2 hours or less per day.

However, the same increase in risk did not apply when the hours of sitting took place at work — participants who sat for extended periods in the office did not have a higher cardiovascular risk than those who spent little time sitting at work. The fix? The researchers suggest that replacing some TV downtime with moderate to vigorous exercise could counteract the increase in cardiovascular risk. In fact, they noted that individuals who sat watching TV for 4 or more hours each day but also did 150 minutes or more of exercise per week did not have a heightened risk of heart health issues or premature death.