This article details how the Garmin GPS data is presented, and how to interpret it.
Sample GPS data below:
|
Variable in the GPS dataset |
Meaning |
|
act_index |
Index of activity (#) |
|
start_time |
Unix Start time of the activity |
|
start_time_offset |
Offset to add to start time to derive the “local” time of the device that captured the data (hr) |
|
start_time_local |
Local start time of the activity |
|
activity_type |
Text description of the activity type |
|
clock_duration_in_seconds |
Length of the monitoring period of “clock time” of this sample (sec) |
|
elevation_in_meters |
Elevation (m) |
|
heart_rate |
Heart rate (#/min) |
|
latitude_in_degree |
Latitude in decimal degrees (DD) |
|
longitude_in_degree |
Longitude in decimal degrees (DD) |
|
moving_duration_in_seconds |
The amount of “timer time” during which the athlete was moving (above a threshold speed) (sec) |
|
speed_meters_per_second |
Velocity (m/s) |
|
steps_per_minute |
Step frequency (#/min) |
|
time_duration_in_seconds |
Length of the monitoring period of “timer time” of this sample (sec) |
|
total_distance_in_meters |
Total accumulating distance of this activity (m) |
Tip: In all cases, movingDurationInSeconds <= timerDurationInSeconds <= clockDurationInSeconds.
For example, a user is going for a run. They start the timer at exactly noon. At 12:30, they pause the timer (either manually or using auto-pause) to stop and chat with a friend, and at 12:35 they resume the timer.
At 12:40 they stand still for 2 minutes, waiting on a traffic signal at a busy intersection, then finish their run and manually stop the timer at 1:00 pm.
clockDurationInSeconds = 60 minutes (12:00 - 1:00)
timerDurationInSeconds = 55 minutes (12:00- 12:30 + 12:35 - 1:00)
movingDurationInSeconds= 53 minutes (12:00 - 12:30 + 12:35- 12:40 + 12:42 - 1:00)
Note: In order to activate GPS data collection, participants must manually click "start activity" and "end activity" on the watch face for the necessary time period (e.g. once they leave their home). The activity can last for several hours, however, they must remember to click "start activity" in order to activate the GPS.
Last updated: March 1, 2022