Comparability of published cut‐points for the assessment of physical activity: Implications for data harmonization

Abstract

This study aimed to compare estimations of sedentary time (SED) and time spent in physical activity (PA) intensities in children with overweight/obesity across different age‐appropriate cut‐points based on different body‐worn attachment sites and acceleration metrics. A total of 104 overweight/obese children (10.1 ± 1.1 years old, 43 girls) concurrently wore ActiGraph GT3X+ accelerometers on their right hip and non‐dominant wrist for 7 days (24 hours). Euclidean norm −1 g (ENMO) and activity counts from both vertical axis (VACounts) and vector magnitude (VMCounts) were derived. We calculated estimates of SED and light, moderate, vigorous, and moderate‐to‐vigorous (MVPA) intensity PA using different published cut‐points for children. The prevalence of children meeting the recommended 60 min/d of MVPA was calculated. The time spent in SED and the different PA intensities largely differed across cut‐points based on different attachment sites and acceleration metrics (ie, SED = 11‐252 min/d; light PA = 10‐217 min/d; moderate PA = 1‐48 min/d; vigorous PA = 1‐35 min/d; MVPA = 4‐66 min/d). Consequently, the prevalence of children meeting the recommended 60 min/d of MVPA varied from 8% to 96% of the study sample. The present study provides a comprehensive comparison between available cut‐points for different attachment and acceleration metrics in children. Furthermore, our data clearly show that it is not possible (and probably will never be) to know the prevalence of meeting the PA guidelines based on accelerometer data since apparent differences range from almost zero to nearly everyone meeting the guidelines.

Associations between physical activity, body composition, and physical fitness in the transition from preschool to school

“…3,6,38 Comparison of findings between studies has been made more complex by the variability of accelerometer placement location and the data processing criteria chosen for PA analyses. 41,42 Furthermore, variations in adjustment patterns may affect the outcomes, as well the variating age of participants. Physical fitness is an important marker of health in children and adolescents.…”

Associations of Objectively-Assessed Physical Activity and Sedentary Time with Hippocampal Gray Matter Volume in Children with Overweight/Obesity

“…Accelerometer data collection and processing criteria are described elsewhere [27,28]. In brief, participants were required to wear accelerometers ActiGraph GT3X+ (ActiGraph, Pensacola, FL, USA) on their non-dominant wrist for 7 consecutive days, and to complete a sleep log with information on time to bed and time out of bed every day.…”

Cut‐point‐free accelerometer metrics to assess children’s physical activity: An example using the school day

“…Cut-points are a way to quantify accumulated time in PA intensity thresholds by calibrating accelerometer data against a criterion measure, such as indirect calorimetry. 10 Cut-points enable accelerometer data to be presented and interpreted in relation to public health guidance (eg, 60-minutes daily MVPA for children). Free-living PA estimates derived from cut-points are though prone to bias, because the cut-points used are specific to the original calibration protocols and sample populations.…”