The Feasibility of Reducing and Measuring Sedentary Time among Overweight, Non-Exercising Office Workers

Abstract EN

This study examined the feasibility of reducing free-living sedentary time (ST) and the convergent validity of various tools to measure ST.

Twenty overweight/obese participants wore the activPAL (AP) (criterion measure) and ActiGraph (AG; 100 and 150 count/minute cut-points) for a 7-day baseline period.

Next, they received a simple intervention targeting free-living ST reductions (7-day intervention period).

ST was measured using two questionnaires following each period.

ST significantly decreased from 67% of wear time (baseline period) to 62.7% of wear time (intervention period) according to AP (n = 14, P<0.01).

No other measurement tool detected a reduction in ST.

The AG measures were more accurate (lower bias) and more precise (smaller confidence intervals) than the questionnaires.

Participants reduced ST by ~5%, which is equivalent to a 48_min reduction over a 16-hour waking day.

These data describe ST measurement properties from wearable monitors and self-report tools to inform sample-size estimates for future ST interventions.