Purpose: Explore environment-related patterns of GPS signal-loss, levels of objectively measured physical activity (PA) during periods of GPS signal loss, and the effect of missing GPS data on relationships between environmental variables, PA and sedentary behavior.
Methods: Eight free-living studies using GPS and accelerometer devices were pooled, representing a range ...
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 examine the cross-sectional associations of objectively derived physical activity and sedentary time with cardiometabolic biomarkers, including the potential collective impact of shifting time use from less towards more active behaviors.
Methods: Overweight/obese and/or physically inactive adults with type 2 diabetes (n=294; mean age = 58.0 [SD 8.5] years) wore Actigraph ...
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: Weather conditions, along with day length, are proposed as the main drivers of the seasonal patterns in children’s physical activity (PA). This study examines the relationship between rainfall and PA among 9-10 year old children in Norfolk, UK, and how this changes as they age.
Methods: Participants were 283 ...
Purpose: While gender differences in physical activity levels have been well documented in the literature, reasons contributing to lower activity levels in females in adulthood are not completely known. One potential mechanism to consider is differences in enjoyment of physical activity. The primary purpose of the study was to examine ...
Purpose: Increasing physical activity (PA) may be an important non-pharmacological approach to improve sleep quality but it is not clear how level and timing and co-current light exposure influence sleep quality. PA time outdoors may be more beneficial for sleep, but only recently has it been possible to measure sleep, ...