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Updated: Jan 31, 2026

Assessment of Physical Activity Intensity with Accelerometers and Oxygen Consumption
Published on: June 20, 2025
Influence of the low-frequency extension filter on accelerometer-based activity measurements in people with HIV: a
Andre P Dos Santos1, Vitor H F Oliveira1, Amanda L Willig2
1University of Washington, Seattle, WA.
None:
Comparing ActiGraph Low-Frequency Extension (LFE) vs. normal filters on accelerometer-derived physical activity and sedentary behavior in 492 people with HIV. Participants wore ActiGraph 7-10 days; metrics (sedentary bouts, light physical activity, MVPA, steps) analyzed with both filters using Wilcoxon and Quade's ANCOVA. LFE increased MVPA (213.5 vs. 162.4 min/week) and steps (11 239 vs. 4853/day; P < 0.001) with minimal effects on sedentary bouts/light physical activity; effects were consistent across subgroups, indicating caution when comparing studies with different filters.
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