Even if you do moderate exercise at the gym or at home, prolonged sitting is proving to be a risk factor for cardiovascular disease and diabetes. So says a study of post-menopausal women released this spring by the Women’s Health Initiative (WHI).
Researchers blame the negative cardiometabolic effects of sitting in a chair for many hours each day (six hours or more).
The study looked at more than 71,000 women aged 50 to 79 and related hours of sitting each day to daily activity levels from the 1990s to later outcomes. The study observed women who sit all day over the course of five years who achieved high, medium and low activity levels outside of work.
As you would expect, the more time spent sitting pushed up cardiovascular risk in the inactive and low- and medium-activity groups. The highest cardiovascular risk was for inactive women who reported sitting at least 10 hours a day.
The one exception to cardiovascular disease risk was for women at the very highest level of activity, which translated to about seven hours of walking or four to five hours of jogging or running each week. These heavy day sitters did not appear to have a higher risk of heart disease, according to the study.
Surprisingly, women in the medium-activity group who were meeting physical activity guidelines of two and a half hours per week of moderate exercise did show an increased risk of heart disease and stroke if they sat all day at work. The study also found that women who sat more tended to exercise less.
Many other studies are coming out with these same results, showing higher mortality rates for both men and women who are completely sedentary for six hours or more each day.
The question on everyone’s minds is: What can people who have desk jobs do to avoid health concerns?
Researchers say: sit less. The human body has not adapted to our sedentary modern lifestyle. We are born to be active.
Sitting less than five hours per day significantly reduces cardiovascular risk for women in the medium and low activity level. If you have to sit for more than five hours because of your job, other research on this topic is showing that short bursts of activity throughout the day can prove beneficial to health. Even five minutes of exercise each hour can have an impact.
“I have always told my patients a body in motion stays in motion,” says Cleveland Clinic cardiologist Curtis Rimmerman, MD. “Incorporating regular movement throughout the day is important for optimal physical and emotional health. Doing some exercise before work and at the lunch hour can be ways to circumvent an otherwise sedentary job.” More activity is always better, the researchers report. But do not be fooled into believing that achieving exercise guidelines of half an hour a day of activity five times a week is enough. This will not counteract the health issues caused by remaining seated for hours on end – either at work or on the couch!
The findings were published in the April 9 issue of the Journal of the American College of Cardiology. The WHI program was supported by grants from the National Institutes of Health and the U.S. Department of Health and Human Services.