Purpose: The aim of this study was to compare common reduction algorithms for ActiGraph accelerometer data using three software packages in order to identify their impact on the number of subjects with valid data. Methods: 200 adolescents from the UP&DOWN Study wore the GT1M and GT3X ActiGraph ...
Purpose: Limitations in monitoring of physical activity (PA) call for the application of triangulation approaches. The goal of the study is to present a verified triangulation approach to monitor daily PA in adolescents on an example of selected characteristics of PA and to suggest how to interpret the data more ...
Purpose: The objective of this study was to compare accelerometer data taken with an onboard accelerometer in a smartphone (Droid A855) with accelerations recorded by a stand-alone accelerometer (ActiGraph GT3x+). Methods: A smartphone application was developed to record the time varying acceleration from the Droid’s onboard three dimensional ...
Purpose: Being outdoors is as a correlate for enhanced physical activity (PA), but the association has seldom been investigated using objective measures. This paper investigates the association between week day outdoor time and context-specific moderate to vigorous PA (MVPA) by gender. Methods: Children (n=170, 11-16 years old) from the When ...
Purpose: To describe accelerometer-measured PA by time of day, sex, & weight status in a nationally representative sample of youth. Methods: Included youth (6-19 years) from the 2003-6 National Health & Nutrition Examination Surveys had at least one 10+ hour weekday of accelerometer data (N=4852; 50% male). Temporal patterns were represented by ...
Purpose: To assess the associations between 1) baseline objectively-measured activity intensity (sedentary (SED), moderate (MPA) or vigorous (VPA) activity) and 4-year change in adiposity, and between 2) 4-year change in activity intensity and adiposity at follow-up. Methods: Analyses of longitudinal data from the SPEEDY study, including all participants with valid data at ...
Purpose: To compare relations of neighborhood walkability and home equipment to (1) total and (2) location-specific physical activity. Methods: 290 adolescents (M age=14.1±1.4 years; 45% girls; 74.7% White non-Hispanic) wore GPS and accelerometers for 5.4±1.9 days set to record at 30-second epochs. GIS was used to calculate a walkability index (sum of z-scores for density, mixed-use, ...
Purpose: Environmental characteristics of home neighbourhoods are hypothesised to be associated with residents’ physical activity levels, yet many studies report only weak associations. We propose this is in part a result of inappropriate definitions of what constitutes a neighbourhood. We objectively measured the distance that adolescents roamed from home to ...
Purpose: To examine whether change in SB and PA associated with a change in weight status over 24-months. Methods: Data were from Identifying Determinants of Eating and Activity (IDEA), a 3-year longitudinal cohort study that assessed the etiology of adolescent obesity. PA and SB were assessed using the ActiGraph (Model 7164; ...
Background: Few randomized trials attempt to improve insulin sensitivity and associated metabolic risks in overweight youth, particularly Latino adolescents. Purpose::The aims of the present pilot study are two-fold, (a) to test the efficacy of the intervention by comparing the home-based strength training (HBST) interventions vs. control group (C); ...