Spending too much of the day sitting has been linked to weight gain, high blood pressure, high cholesterol, Type 2 diabetes and heart disease. Might it also age you biologically?
The study analyzed data on 1,481 older women (age 79, on average) who wore movement trackers to record their activity. They also had DNA samples extracted to measure the length of telomeres, the caps at the end of DNA strands that protect chromosomes from wearing down, somewhat like the plastic tips at the end of shoelaces. Telomeres naturally become shorter with age. On average, the participants were sedentary for about nine hours a day. Women who were the most sedentary had the shortest telomeres, a length that the researchers said correlated to their being biologically older by eight years than their actual age. Abnormally shortened telomeres were not found among women who recorded at least 30 minutes a day of moderate to vigorous physical activity.
Older women. Experts say that adults should get at least 150 minutes a week of moderate-intensity aerobic activity, such as brisk walking, and perform exercises that strengthen all major muscle groups at least twice a week. Such exercises can include yoga, lifting weights and gardening that involves digging or shoveling.
Whether the findings would apply to men or younger women was not tested. Some of the data on activity came from the participants’ responses on questionnaires.
Online Jan. 18 in the American Journal of Epidemiology (academic.oup.com/aje; click on “More Content,” then “Advanced Articles”)
Physical activity recommendations for adults can be found at cdc.gov/physicalactivity. More on the benefits of exercise and other aspects of healthy aging is available at nihseniorhealth.gov (click on “Healthy Aging”).
The research described in Quick Study comes from credible, peer-reviewed journals.