Potential Effects of Replacing Sedentary Time With Short Sedentary Bouts or Physical Activity on Mortality: A National Cohort Study.

Potential Effects of Replacing Sedentary Time With Short Sedentary Bouts or Physical Activity on Mortality: A National Cohort Study.
Am J Epidemiol. 2018 Dec 14;:
Authors: Diaz KM, Duran AT, Colabianchi N, Judd SE, Howard VJ, Hooker SP
Abstract
Little is known concerning the type of activity that should be substituted for sedentary time and its potentially most hazardous form (prolonged sedentary bouts) to impart health benefit. We used isotemporal substitution techniques to examine whether 1) replacing total sedentary time with light- or moderate-intensity physical activity (LIPA, MVPA) and 2) replacing prolonged sedentary bouts with shorter sedentary bouts is associated with reductions in all-cause mortality risk. Participants (n = 7,999) from the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study, a national cohort of US adults ≥45 years, were studied. Sedentary time was measured by accelerometry between 2009 and 2013. There was a beneficial association on mortality risk for replacing total sedentary time with both LIPA (per 30-minutes HR = 0.83; 95% CI: 0.80, 0.87) and MVPA (per 30-minutes HR = 0.65; 95% CI: 0.50, 0.85). Similarly, there was a beneficial association of replacing prolonged sedentary bout time with LIPA and MVPA, but not for replacement with shorter sedentary bouts (per 30-minutes HR = 1.00; 95% CI: 0.96, 1.03). These findings suggest short sedentary bouts still carry mortality risk a...

Source: Am J Epidemiol - December 14, 2018 Category: Epidemiology Authors: Diaz KM, Duran AT, Colabianchi N, Judd SE, Howard VJ, Hooker SP Tags: Am J Epidemiol Source Type: research