Pace Fluctuations - Sharp Rises & Dropouts

I consistently get Pace graphs like this after a run or hike.

Running

Hiking

Possible dropouts in GPS or a swift motion of the arm whilst bringing the watch up to view data?

0 trux over 5 years ago

Most likely GPS dropouts, as you wrote. Arm motion won't have any impact on the pace. Zoom close on the map, or export the activity in a TCX or GPX format, open it in a text editor, and verify the coordinates of the key points in the critical places.

0 Tom over 5 years ago in reply to trux

I thought the watch got the pace from the GPS and accelerometer? Like the Fused pace that my Suunto watch has?

I thought all modern watches have that feature, or does it just fall back on the accelerometer for GPS dropouts?

0 trux over 5 years ago in reply to Tom

An accelerometer measures the acceleration, not the velocity. Although the velocity can be theoretically derived from the accelartion over certain time, and the vector of the acceleration, in the reality such calculation is pretty much useless and very much inaccurate (especially due to limited sensitivity of this type of accelerometers, and their inability to detect low values, air drag, friction, etc). Using the GPS, and just interpolating the values in case of a signal drop out, will be likely much more accurate.