Open Access. Powered by Scholars. Published by Universities.®

Kinesiology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Kinesiology

Impact Of Accelerometer Data Processing Decisions On The Sample Size, Wear Time And Physical Activity Level Of A Large Cohort Study, Sarah Kozey Keadle, Eric Shiroma, Patty Freedson, I-Min Lee Jan 2014

Impact Of Accelerometer Data Processing Decisions On The Sample Size, Wear Time And Physical Activity Level Of A Large Cohort Study, Sarah Kozey Keadle, Eric Shiroma, Patty Freedson, I-Min Lee

Patty S. Freedson

Background Accelerometers objectively assess physical activity (PA) and are currently used in several large-scale epidemiological studies, but there is no consensus for processing the data. This study compared the impact of wear-time assessment methods and using either vertical (V)-axis or vector magnitude (VM) cut-points on accelerometer output. Methods Participants (7,650 women, mean age 71.4 y) were mailed an accelerometer (ActiGraph GT3X+), instructed to wear it for 7 days, record dates and times the monitor was worn on a log, and return the monitor and log via mail. Data were processed using three wear-time methods (logs, Troiano or Choi algorithms) and …


Validation Of A Previous Day Recall For Measuring The Location And Purpose Of Active And Sedentary Behaviors Compared To Direct Observation, Sarah Kozey Keadle, Kate Lyden, Amanda Hickey, Evan L. Ray, Jay H. Fowke, Patty S. Freedson, Charles E. Matthews Dec 2013

Validation Of A Previous Day Recall For Measuring The Location And Purpose Of Active And Sedentary Behaviors Compared To Direct Observation, Sarah Kozey Keadle, Kate Lyden, Amanda Hickey, Evan L. Ray, Jay H. Fowke, Patty S. Freedson, Charles E. Matthews

Patty S. Freedson

Purpose Gathering contextual information (i.e., location and purpose) about active and sedentary behaviors is an advantage of self-report tools such as previous day recalls (PDR). However, the validity of PDR’s for measuring context has not been empirically tested. The purpose of this paper was to compare PDR estimates of location and purpose to direct observation (DO). Methods Fifteen adult (18–75 y) and 15 adolescent (12–17 y) participants were directly observed during at least one segment of the day (i.e., morning, afternoon or evening). Participants completed their normal daily routine while trained observers recorded the location (i.e., home, community, work/school), purpose …


Calibrating A Novel Multi-Sensor Physical Activity Measurement System, D. John, S. Liu, J. Saski, C. Howe, J. Staudenmayer, R. Gao, Patty Freedson Sep 2011

Calibrating A Novel Multi-Sensor Physical Activity Measurement System, D. John, S. Liu, J. Saski, C. Howe, J. Staudenmayer, R. Gao, Patty Freedson

Patty S. Freedson

Advancing the field of physical activity (PA) monitoring requires the development of innovative multi-sensor measurement systems that are feasible in the free-living environment. The use of novel analytical techniques to combine and process these multiple sensor signals is equally important. This paper, describes a novel multi-sensor ‘Integrated PA Measurement System’ (IMS), the lab-based methodology used to calibrate the IMS, techniques used to predict multiple variables from the sensor signals, and proposes design changes to improve the feasibility of deploying the IMS in the free-living environment. The IMS consists of hip and wrist acceleration sensors, two piezoelectric respiration sensors on the …