Research Database

18 results for "Wear time"

How many days are needed to estimate wrist-worn accelerometry-assessed physical activity during the second trimester in pregnancy?

  • Published on June 27, 2019

Background Objective methods to measure physical activity (PA) can lead to better cross-cultural comparisons, monitoring temporal PA trends, and measuring the effect of interventions. However, when applying this technology in field-work, the accelerometer data processing is prone to methodological issues. One of the most challenging issues relates to standardizing total ...


Comparison of Weekend and Weekday Physical Activity Patterns in Chronic Obstructive Pulmonary Disease (COPD) and Non-COPD Participants by Daily Activity Level

  • Published on May 19, 2019

Rationale: Physical activity endpoints are of interest in chronic obstructive pulmonary disorder (COPD), but in considering what constitutes a "valid" wear time for activity monitors, there is still debate whether monitors should be worn over a period incorporating both weekdays and weekends. We explored whether activity patterns differ significantly between ...


Comparison of Two Generations of ActiGraph Accelerometers: The CARDIA Study

  • Published on Jun 2018

Purpose: This study aimed to examine the comparability of the ActiGraph 7164 and wGT3X-BT wear time, count-based estimates, and average time per day in physical activity of different intensities. Methods: We studied 87 Coronary Artery Risk Development in Young Adults (CARDIA) participants 48-60 yr of age who simultaneously wore the 7164 and ...


Objectively measured physical activity of hospital shift workers

  • Published on Jan 22, 2018

Objectives: Shift work may alter workers' leisure-time and occupational physical activity (PA) levels, which might be one of the potential underlying mechanisms of the negative health effects of shift work. Therefore, we compared objectively measured PA levels between hospital shift and non-shift workers. Methods: Data were used from Klokwerk+, a ...


Estimating Energy Expenditure with ActiGraph GT9X Inertial Measurement Unit.

  • Published on May 2018

Purpose: The purpose of this study was to explore whether gyroscope and magnetometer data from the ActiGraph GT9X improved accelerometer-based predictions of energy expenditure (EE). Methods: Thirty participants (mean ± SD: age, 23.0 ± 2.3 yr; body mass index, 25.2 ± 3.9 kg·m) volunteered to complete the study. Participants wore five GT9X monitors (right ...


Physical activity quantified by questionnaire and accelerometry in schoolchildren. A comparison

  • Published on Feb 9, 2018

Introduction: Questionnaires have long been the tool of choice for the measurement of physical activity in large population groups, however, they depend on the accuracy with which they are answered. Accelerometers, on the other hand, can directly measure physical activity, eliminate subjectivity and, allow comparisons with instruments such as questionnaires. ...


The Impact of Low Accelerometer Wear Time on the Estimates and Application of Sedentary Behavior and Physical Activity Data in Adults

  • Published on Dec 1, 2017

Background: This investigation sought to determine how accelerometer wear (1) biased estimates of sedentary behavior (SB) and physical activity (PA), (2) affected misclassifications for meeting the Physical Activity Guidelines for Americans, and (3) impacted the results of regression models examining the association between moderate to vigorous physical activity (MVPA) and a clinically relevant ...


Daily physical activity patterns from hip- and wrist-worn accelerometers

  • Published on Sep 21, 2016

Accelerometer wear location may influence physical activity estimates. This study investigates this relationship through the examination of activity patterns throughout the day. Participants from the aging research evaluating accelerometry (AREA) study (n men  =  37, n women  =  47, mean age (SD)  =  78.9 (5.5) years) were asked to wear accelerometers in a free-living environment for 7 d ...


Accelerometer Data Collection and Processing Criteria to Assess Physical Activity and Other Outcomes: A Systematic Review and Practical Considerations

  • Published on March 16, 2017

Background: Accelerometers are widely used to measure sedentary time, physical activity, physical activity energy expenditure (PAEE), and sleep-related behaviors, with the ActiGraph being the most frequently used brand by researchers. However, data collection and processing criteria have evolved in a myriad of ways out of the need to answer unique ...


Improving wear time compliance with a 24-hour waist-worn accelerometer protocol in the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE)

  • Published on Feb. 11, 2015

Background: We compared 24-hour waist-worn accelerometer wear time characteristics of 9–11 year old children in the International Study of Childhood Obesity, Lifestyle and the Environment (ISCOLE) to similarly aged U.S. children providing waking-hours waist-worn accelerometer data in the 2003–2006 National Health and Nutrition Examination Survey (NHANES). Methods: Valid cases were defined ...