Background: Cut-points for physical activity intensity are developed from the relationship between oxygen uptake (VO2) and rate of activity counts determined with accelerometry. This practice assumes that the relationship between VO2 and activity-count rate is stable within people, but this has not been directly examined. Purpose: To examine whether the ...
Purpose: The purpose of this study was two-fold; to compare accelerations between dominant and non-dominant wrists during structured activity bouts; and to determine whether there are differences in wrist accelerations (dominant and non-dominant) between age groups during structured activity bouts. Methods: Participants aged 23 to 79 y performed a block of ten ...
Background: Accelerometer-derived total activity count is a measure of total physical activity (PA) volume. The purpose of this study was to develop age- and gender-specific percentiles for daily total activity counts (TAC), minutes of moderate-to-vigorous physical activity (MVPA), and minutes of light physical activity (LPA) in U.S. adults. Purpose: ...
Background: Many studies used the older ActiGraph (7164) for physical activity measurement, but this model has been replaced with newer ones (e.g., GT3X+). The assumption that new generation models are more accurate has been questioned, especially for measuring lower intensity levels. The low-frequency extension (LFE) increases the low-intensity sensitivity ...
Background: Accelerometry is increasingly being recognized as an accurate and reliable method to assess free-living physical activity (PA) in children and adolescents. However, accelerometer data reduction criteria remain inconsistent, and the consequences of excluding participants in for example intervention studies are not well described. In this study, we investigated how ...
The triaxial GT3X+ accelerometer can measure activity counts in the vertical, horizontal right to left, horizontal front to back planes, and can generate a summative score of the three axes represented by vector magnitude (VM). Information on the reliability of the GT3X+ at the hip, wrist and ankle ...
Introduction The National Health and Nutrition Examination Survey (NHANES) included accelerometry in the 2003–2006 data collection cycles. Researchers have used these data since their release in 2007, but the data have not been consistently treated, examined, or reported. The objective of this study was to aggregate data from studies using NHANES accelerometry ...
Purpose Accurate, nonintrusive and feasible methods are needed to predict energy expenditure (EE) and physical activity (PA) levels in preschoolers. Herein, we validated cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on accelerometry and heart rate (HR) for prediction of EE using room calorimetry and doubly ...
Introduction Technology advances and manufacturing efficiency improvements have drastically increased the options and flexibility available to users of accelerometer-based products. These advancements have led to confusion among activity monitor users, and many have been led to believe that device output normalization is an obvious and easy step. In truth, there ...
Aim This study evaluated objectively measured physical activity and sedentary time among Finnish schoolaged children from grades 1 to 6 (ages 7 to 12 years) and compared the results between boys and girls, and between different age groups. Methods The study population consisted of 568 Finnish boys and girls from grades 1 to 6 (mean age 9.9 years, ...