Physical Activity Objective Monitors
There are three physical activity objective monitors and a single combined wear log covering both monitors.
The ActiGraph GT3X physical activity monitor measures acceleration in 3 axis, body position, and ambulation (steps). Participants wore the ActiGraph GT3X monitor two times during the study with six months between administrations. The monitor was placed on an elastic belt and participants were instructed to wear the belt on their waist with the monitor positioned over their right hip, directly under the right armpit. Participants were asked to wear the ActiGraph GT3X monitors all day, including naptimes, for seven days, and to remove the monitors when showering, bathing, and swimming and for bed at night. Participants were asked to wear the monitor for seven days, but some participants chose to wear the monitor for additional days beyond the specified week.
ActiGraph GT3X monitor data are provided in three formats: by 60-second, 10-second and 1 second epoch.
A small portion of the raw one second ActiGraph data is not included in the 10-second and 60-second summaries due to persistent invalid or out of range output, suggesting that the device had malfunctioned. The first 7 days of data (the protocol period) are always kept. Days outside the first week may be kept if the physical activity log indicates continued wear.
You may view data dictionaries and formats for the ActiGraph files. Datasets can be obtained by submitting a request.
ACTIGRAPH 10 & 60–SECOND EPOCH DATA
ACTIGRAPH 1-SECOND EPOCH DATA