title: Validity of hip-mounted uniaxial accelerometry with heart-rate monitoring vs. triaxial accelerometry in the assessment of free-living energy expenditure in young children: the IDEFICS Validation Study.
abstract: One of the aims of Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants (IDEFICS) validation study is to validate field measures of physical activity (PA) and energy expenditure (EE) in young children. This study compared the validity of uniaxial accelerometry with heart-rate (HR) monitoring vs. triaxial accelerometry against doubly labeled water (DLW) criterion method for assessment of free-living EE in young children. Forty-nine European children (25 female, 24 male) aged 4-10 yr (mean age: 6.9 ± 1.5 yr) were assessed by uniaxial ActiTrainer with HR, uniaxial 3DNX, and triaxial 3DNX accelerometry. Total energy expenditure (TEE) was estimated using DLW over a 1-wk period. The longitudinal axis of both devices and triaxial 3DNX counts per minute (CPM) were significantly (P < 0.05) associated with physical activity level (PAL; r = 0.51 ActiTrainer, r = 0.49 uniaxial-3DNX, and r = 0.42 triaxial Σ3DNX). Eight-six percent of the variance in TEE could be predicted by a model combining body mass (partial r(2) = 71%; P < 0.05), CPM-ActiTrainer (partial r(2) = 11%; P < 0.05), and difference between HR at moderate and sedentary activities (ModHR - SedHR) (partial r(2) = 4%; P < 0.05). The SE of TEE estimate for ActiTrainer and 3DNX models ranged from 0.44 to 0.74 MJ/days or ∼7-11% of the average TEE. The SE of activity-induced energy expenditure (AEE) model estimates ranged from 0.38 to 0.57 MJ/day or 24-26% of the average AEE. It is concluded that the comparative validity of hip-mounted uniaxial and triaxial accelerometers for assessing PA and EE is similar.
authors.affiliation: College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland.
authors.forename: Robert
authors.initials: R
authors.lastname: Ojiambo
authors.forename: Kenn
authors.initials: K
authors.lastname: Konstabel
authors.forename: Toomas
authors.initials: T
authors.lastname: Veidebaum
authors.forename: John
authors.initials: J
authors.lastname: Reilly
authors.forename: Vera
authors.initials: V
authors.lastname: Verbestel
authors.forename: Inge
authors.initials: I
authors.lastname: Huybrechts
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sioen
authors.forename: José A
authors.initials: JA
authors.lastname: Casajús
authors.forename: Luis A
authors.initials: LA
authors.lastname: Moreno
authors.forename: German
authors.initials: G
authors.lastname: Vicente-Rodriguez
authors.forename: Karin
authors.initials: K
authors.lastname: Bammann
authors.forename: Bojan M
authors.initials: BM
authors.lastname: Tubic
authors.forename: Staffan
authors.initials: S
authors.lastname: Marild
authors.forename: Klaas
authors.initials: K
authors.lastname: Westerterp
authors.forename: Yannis P
authors.initials: YP
authors.lastname: Pitsiladis
mesh_terms: D056044:Actigraphy / Q000295:instrumentation*; D000367:Age Factors; D002153:Calorimetry, Indirect; D002648:Child; D002675:Child, Preschool; D017666:Deuterium Oxide; D004734:Energy Metabolism; D004867:Equipment Design; D005060:Europe; D005260:Female; D006339:Heart Rate; D006615:Hip; D006801:Humans; D008297:Male; D008954:Models, Biological; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D009043:Motor Activity; D012044:Regression Analysis; D015203:Reproducibility of Results; D057185:Sedentary Behavior; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors
chemical_list: D017666:Deuterium Oxide