The correlation between objective and self-reported measures of physical activity varies between studies. We examined this association and whether it differed by demographic factors or socioeconomic status (SES). Data were from 3,975 Whitehall II (United Kingdom, 2012-2013) participants aged 60-83 years, who completed a physical activity questionnaire and wore an accelerometer on their wrist fo...

BACKGROUND This study was designed to develop a prediction algorithm that would allow the Previous Day Physical Activity Recall (PDPAR) to be equated with temporally matched data from an accelerometer. METHODS Participants (n = 121) from a large, school-based intervention wore a validated accelerometer and completed the PDPAR for 3 consecutive days. Physical activity estimates were obtained f...

Acceleration, an important dynamic parameter, is used widely in researching on aircraft mechanical structure fatigue, shock and so on, as it is in proportion to force and load. Piezoelectric sensor is a kind of sensor that most widely used in measuring acceleration, is also called acceleration sensor or accelerometer, because its impulse response is excellent and is suitable for measuring shock...

BACKGROUND The purpose of this paper is to evaluate self-reported physical activity of young adults using 1-week and 1-year recall measures with an accelerometer as the criterion measure. METHODS Participants were a subsample (N = 121, 24 ± 1.7 yrs) from a large longitudinal cohort study. Participants completed a detailed 1-year physical activity recall, wore an accelerometer for 1 week and t...

BACKGROUND To be able to draw any conclusions regarding the health effects of occupational physical activity (OPA), more information is needed regarding valid measures to assess OPA. Aims were to compare OPA as assessed with the International Physical Activity Questionnaire long version (IPAQ-L) with OPA assessed with an accelerometer and to assess the contribution of OPA to total PA. METHODS...

BACKGROUND The International Physical Activity Questionnaire-Short Form (IPAQ-S) has been evaluated against accelerometer-determined physical activity measures in small homogenous samples of adults in the United States. There is limited information about the validity of the IPAQ-S in diverse US samples. METHODS 142 Blacks residing in low-income housing completed the IPAQ-S and wore an acceler...

Self-report measures of physical activity (PA) are easy to use and popular but their reliability is often questioned. Therefore, the general aim of the present study was to investigate the association of PA questionnaires with accelerometer derived PA, in a sample of adolescent boys. In total, 191 pubertal boys (mean age 14.0 years) completed three self-report questionnaires and wore an acceler...

OBJECTIVE The overarching goal of this study was to examine the use of triaxial accelerometers in measuring upper-extremity motions to monitor upper-extremity-exercise compliance. There were multiple questions investigated, but the primary objective was to investigate the correlation between visually observed arm motions and triaxial accelerometer activity counts to establish fundamental activi...

The proof-of-concept demonstration of a microfiber-based flexural disc accelerometer is presented. The reduced microfiber size and bending radii give rise to high device compactness and responsivity. A flexural disc accelerometer manufactured from a 10 mm long microfiber showed a performance of ~2.2 rad/g, with the responsivity expected to increase proportionally with the microfiber length.

Hypergravity accelerators are a type of large machinery used for gravity training or medical research. A failure such equipment can be serious problem in terms safety costs. This paper proposes prediction model that proactively prevent failures may occur hypergravity accelerator. An experiment was conducted to evaluate the performance method proposed this paper. 4-channel accelerometer attached...