Article

OBJECTIVE: To create and compare individual and group-based cut-points for wrist
accelerometry that correspond to moderate-to-vigorous physical activity (MVPA) in
people with spinal cord injury (SCI). DESIGN: Participants completed a graded
treadmill-wheeling test while being assessed for oxygen consumption,
wrist-acceleration vector magnitude, and spoke acceleration. Oxygen consumption
was converted to SCI metabolic equivalents (METs), and linear regression was
applied to determine an individualized vector magnitude cut-point (counts per
minute, VM-CPM) corresponding with MVPA (>/=3 SCI METs). Multilevel linear
regression was applied to determine a group MVPA cut-point. Participants then
completed a 6-day monitoring period while wearing the accelerometers. SETTING: A
local SCI research center. PARTICIPANTS: Manual wheelchair users (N=20; aged
31-64y; injury levels, C5 to L2) with chronic (>1y) SCI. INTERVENTIONS: Not
applicable. MAIN OUTCOME MEASURES: Mean total daily MVPA, wheeled MVPA, and
nonwheeled MVPA were calculated using both the individual and group cut-points.
Agreement on measures of minutes per day of MVPA between the individual and group
mean cut-point method was assessed using Bland-Altman plots. RESULTS: Individual
cut-points for MVPA ranged from 6040 to 21,540 VM-CPM, with a group cut-point of
11,652 (95% confidence interval, 7395-15,909). For total daily MVPA, Bland-Altman
analysis revealed a bias of .22+/-33.0 minutes, with 95% limits of agreement from
-64.5 to 64.9 minutes, suggesting a large discrepancy between total MVPA
calculated from individual and group mean cut-points. CONCLUSIONS: Individual
calibration of wrist-worn accelerometry is recommended for effective habitual PA
monitoring in this population.
CI - Copyright (c) 2017 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS