Have We Improved Our Sedentary Behaviors Over The Past Twenty Years?

Considering the risks of cardiovascular disease related to sedentary behaviors, the study conducted by Yang L, Cao C, Kantor ED, et al. illustrates concerning—though not surprising— data. Greater effort to reduce sedentary habits together with promotions of regular physical activity are essential to improving public health.

Methods:

Researchers analyzed data from the National Health and Nutrition Examination Survey (NHANES 2001-2016) for serial, cross-sectional analysis of United States residents of children aged 5-11 years (2001-2016); adolescents, 12-19 years (2003-2016); and adults, ≥20 years (2003-2016). Pervasiveness of sedentary behaviors was studied. Cases of sedentary behaviors included sitting watching television or videos for more than or equal to two hours per day, computer use outside of work or school for more than or equal to one hour per day, and total sitting time (hours per day in those aged ≥12 years).

Results:

Data from 51,896 individuals (mean age 37.2 years, 50% female) were included in this study including 10,359 children, 9,639 adolescents, and 31,898 adults. The estimated prevalence of sitting watching television or videos for ≥2 hours/day was high among all ages (children, 62% [95% CI, 57-67%]; adolescents, 59% [95% CI, 54-65%]; adults, 65% [95% CI, 61-69%]; adults aged 20-64 years, 62% [95% CI, 58-66%]; and ≥65 years, 84% [95% CI, 81-88%] in the 2015-2016 cycle). From 2001-2016, the trends decreased among children over time (difference, −3.4% [95% CI, −11% to 4.5%]; p for trend = 0.004), driven by non-Hispanic white children. Sedentary trends were stable among adolescents (−4.8% [95% CI, −12% to 2.3%]; p for trend = 0.60) and among adults aged 20-64 years (−0.7% [95% CI, −5.6% to 4.1%]; p for trend = 0.82). Sedentary behaviors increased among adults aged ≥65 years (difference, 3.5% [95% CI, −1.2% to 8.1%]; p for trend = 0.03). The estimated prevalence of computer use outside school or work for ≥1 hour/day increased in all ages including children (difference, 13% [95% CI, 5.6-21%]); adolescents (difference, 4.8% [95% CI, −1.8% to 11%]); and adults (difference, 21% [95% CI, 18-25%]). From 2007 to 2016, total hours per day of sitting time increased among adolescents and adults by 1 hour to 8.2 hours (95% CI, 7.9-8.4) for adolescents, and to 6.4 (95% CI, 6.2-6.6) for adults.

Conclusions:

The researchers determined that in this survey, which is representative of the US population from 2001-2016, the approximated prevalence of sitting watching television or videos for greater than or equal to two hours per day generally remained high and unchanged. The estimated prevalence of computer use during free time rose among all age groups, and the approximated total sitting time grew among adolescents and adults.