Self-reported and objectively measured sedentary behavior in bariatric surgery candidates

Background: Sedentary behavior (SB), independent of physical activity, represents a significant health risk. We previously used objective measures to demonstrate that bariatric surgery candidates engage in high levels of SB overall, but supplementing these measures with subjective reports would provide information about time allocated to different forms of SB. The aim of this study was to examine self-reported time spent performing specific types of SB and discrepancy between self-reported and objectively measured estimates of total sedentary time in bariatric surgery candidates.

Methods: A total of 52 bariatric surgery candidates (87% female; age = 46.2 ± 9.1 years; body mass index [BMI] = 45.3 ± 6.7) completed the 9-item Sedentary Behavior Questionnaire (SBQ) as a subjective measure of SB and wore the SenseWear Armband (SWA; SenseWear, Pittsburgh, PA) as an objective measure. Paired samples t tests and the intraclass correlation coefficient (ICC) assessed measurement discrepancy.

Results: Television-viewing was the most frequently performed type of SB (2.7 ± 1.6 hours per day), followed by paper/computer work (1.9 ± 1.8 hours per day), driving/riding in automobile (1.2 ± 1.1 hours per day), and sitting/talking on telephone (1.1 ± 1.2 hours per day). On average, the SBQ and SWA produced similar estimates of daily sedentary time (hours per day) at the group level (9.6 ± 4.8 versus 9.3 ± 1.9; mean difference = -.34 ± 4.6; P = .59), although agreement between the measures at the individual level was poor (mean absolute value of difference = 3.8 ± 2.8 hours per day; ICC = .22; P = .06).

Conclusion: Television-viewing was the single SB in which participants most frequently engaged and thus may be an important modifiable target for reducing total sedentary time in bariatric surgery candidates. The SBQ and SWA can be used similarly to describe SB levels in this patient population at the group level; however, ability of these measures to produce comparable estimates of sedentary time for any individual patient is limited.