Replacement of leisure-time sedentary behavior with various physical activities and the risk of dementia incidence and mortality: A prospective cohort studyMay 24, 2023
Validation of an Algorithm for Measurement of Sedentary Behaviour in Community-Dwelling Older AdultsJune 7, 2023
A study titled “Breaking Up Prolonged Sitting to Improve Cardiometabolic Risk: Dose–Response Analysis of a Randomized Crossover Trial” was recently published in Medicine and Science in Sports and Exercise. A summary of the paper and citation details are re-posted below. The full article is available here.
Purpose: Sedentary time is ubiquitous in developed nations and is associated with deleterious health outcomes. Physical activity guidelines recommend reductions in sedentary time; however, quantitative guidelines that inform how often and how long sedentary time should be interrupted have not been provided. The purpose of this study was to examine the acute effects of multiple doses of a sedentary break intervention on cardiometabolic risk factors, concurrently evaluating efficacy of varying frequencies and durations of sedentary breaks.
Methods: In a randomized crossover study, middle- and older-age adults (n = 11) completed the following 8-h conditions on five separate days: 1 uninterrupted sedentary (control) condition and four acute (experimental) trials that entailed different sedentary break frequency/duration combinations: every 30 min for 1 min, every 30 min for 5 min, every 60 min for 1 min, and every 60 min for 5 min. Sedentary breaks entailed light-intensity walking. Glucose and blood pressure (BP) were measured every 15 and 60 min, respectively.
Results: Compared with control, glucose incremental area under the curve was significantly attenuated only for the every 30 min for 5-min dose (-11.8[4.7]; P = 0.017). All sedentary break doses yielded significant net decreases in systolic BP from baseline compared with control ( P < 0.05). The largest reductions in systolic BP were observed for the every 60 min for 1 min (-5.2 [1.4] mm Hg) and every 30 min for 5 min (-4.3[1.4] mm Hg) doses.
Conclusions: The present study provides important information concerning efficacious sedentary break doses. Higher-frequency and longer-duration breaks (every 30 min for 5 min) should be considered when targeting glycemic responses, whereas lower doses may be sufficient for BP lowering.
Duran AT, Friel CP, Serafini MA, Ensari I, Cheung YK, Diaz KM. Breaking Up Prolonged Sitting to Improve Cardiometabolic Risk: Dose-Response Analysis of a Randomized Crossover Trial. Med Sci Sports Exerc. 2023;55(5):847-855. doi:10.1249/MSS.0000000000003109