Most Americans Spend 2 or More Hours Per Day Sitting

Despite warnings about the dangers of a sedentary lifestyle, Americans are spending more time sitting now than they were in 2001, according to a recent study.

Investigators from the University of Washington examining sedentary behavior found that most Americans are spending two hours or more everyday sitting and watching television or videos.

Investigators used data from the National Health and Nutrition Examination Survey (NHANES) to examine a cohort of 51,896 individuals from 2001 to 2016. The group was comprised of 10,359 children, 9639 adolescents, and 31,898 adults. Children were defined as being aged between 5 and 11 years, adolescents were considered to be between 12 and 19 years old, and adults were classified as 20 years or older.

Participants were asked two questions, “Over the past 30 days, on average, how many hours per day did you sit and watch television or videos?” and “Over the past 30 days, on average, about how many hours per day did you use a computer or play computer games outside of school or work?”. Respondents could choose between the options of none, less than 1 hour, 1 hour, 2 hours, 3 hours, 4 hours, or 5 hours or more per day. For the primary analyses, investigators further categorized participants into groups that watched less than 2 hours per day and 2 hours or more per day.

Investigators assessed total sitting time among adolescents and adults, but not children, from the 2007-2008 cycle through the 2015-2016 cycle. Authors noted that participants reporting more than 16 hours per day of daily sitting time were excluded as they were considered implausible values.

Investigators found that total daily sitting time increased among adolescents and adults from 2007 to 2016, from 7 hours per day to more than 8 for teenagers, and from 5.5 hours per day to almost 6.5 for adults.

Investigators also noted that most Americans are spending at least 2 hours per day sitting and watching television or videos. Among children, 62% spent at least 2 hours in front of screens, among adolescents that number was 59%, and about 65% of adults between 20 and 64 spent that much time in front of screens.

Investigators noted that from 2015 to 2016, 84% of adults over the age of 65 spent at least 2 hours per day watching television. Across all age groups, investigators found that 28 to 38% of the population spent 3 hours or more per day watching television or videos, while 13 to 23% spent 4 or more hours per day.

Additionally, the authors found that screen time outside of work and school increased over the study period. At least 50% of all individuals across all age groups used a computer during leisure time for more than 1 hour per day in the two most recent years of the study.

In the 65 and older group, the number jumped from 15% of individuals using a computer for an hour per day during leisure time in 2003 to 53% of individuals in 2016. They noted that up to 25% of individuals across all groups used computer outside of work and school for 3 hours or more.

The study’s lead author, Yin Cao, ScD, MPH, epidemiologist and assistant professor of surgery at the Washington University School of Medicine, remarked that she hoped the results of her study could be used as a baseline when examining trends or impacts of public policy.

“Until now, we haven't had data demonstrating the amount of time most Americans spend sitting watching TV or doing other sedentary activities," Cao said. "Now that we have a baseline, on population level and for different age groups, we can look at trends over time and see whether different interventions or public health initiatives are effective in reducing the time spent sitting and nudging people toward more active behaviors."

This study, titled “Trends in Sedentary Behavior Among the US Population, 2001-2016,” was published in the Journal of the American Medical Association.