The influence of minimum sitting period of the ActivPAL™ on the measurement of breaks in sitting in young children

Alghaeed, Z., Reilly, J.J., Chastin, S.F.M., Martin, A. , Davies, G. and Paton, J.Y. (2013) The influence of minimum sitting period of the ActivPAL™ on the measurement of breaks in sitting in young children. PLoS ONE, 8(8), e71854. (doi:10.1371/journal.pone.0071854) (PMID:23977163) (PMCID:PMC3743753)

[img]
Preview
Text
85780.pdf - Published Version
Available under License Creative Commons Attribution.

548kB

Abstract

<p>Background: Sitting time and breaks in sitting influence cardio-metabolic health. New monitors (e.g. activPAL™) may be more accurate for measurement of sitting time and breaks in sitting although how to optimize measurement accuracy is not yet clear. One important issue is the minimum sitting/upright period (MSUP) to define a new posture. Using the activPAL™, we investigated the effect of variations in MSUP on total sitting time and breaks in sitting, and also determined the criterion validity of different activPAL™ settings for both constructs.</p> <p>Methods: We varied setting of MSUP in 23 children (mean (SD) age 4.5 y (0.7)) who wore activPAL™ (24 hr/d) for 5–7 d. We first studied activPAL™ using the default setting of 10 s MSUP and then reduced this to 5 s, 2 s and 1 s. In a second study, in a convenience sample of 30 pre-school children (mean age 4.1 y (SD 0.5)) we validated the activPAL™ measures of sitting time and breaks in sitting at different MSUP settings against direct observation.</p> <p>Results: Comparing settings of 10, 5, 2 and 1 s, there were no significant differences in sitting time (6.2 hr (1.0), 6.3 hr (1.0), 6.4 hr (1.0) and 6.3 hr (1.6), respectively) between settings but there were significant increases in the apparent number of breaks - (8(3), 14(2), 21(4) and 28 (6)/h) at 10, 5, 2 and 1 s settings, respectively. In comparison with direct observation, a 2 s setting had the smallest error relative to direct observation (95% limits of agreement: -14 to +17 sitting bouts/hr, mean difference 1.83, p = 0.2).</p> <p>Conclusion: With activPAL™, breaks in sitting, but not total sitting time, are highly sensitive to the setting of MSUP, with 2 s optimal for young children. The MSUP to define a new posture will need to be empirically determined if accurate measurements of number of breaks in sitting are to be obtained.</p>

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Martin, Dr Anne and Paton, Dr James and Reilly, Prof John
Authors: Alghaeed, Z., Reilly, J.J., Chastin, S.F.M., Martin, A., Davies, G., and Paton, J.Y.
College/School:College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
Journal Name:PLoS ONE
Publisher:Public Library of Science
ISSN:1932-6203
Copyright Holders:Copyright © 2013 The Authors
First Published:First published in PLoS ONE 8(8):e71854
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record