ActivityInfo TotalAscent and totalDescend not accurate

Former Member over 10 years ago

Hi

I have created an APP for a vivoactive which gets some info from the activity info class

Distance = (activityInfo.elapsedDistance.toFloat() * 0.001);
Maxspeed = activityInfo.maxSpeed * 3.6;
Ascend = activityInfo.totalAscent;
Descend = activityInfo.totalDescent;
myTimer = activityInfo.elapsedTime / 1000;

(These are all in the onUpdate(dc) function)

Distance, maxspeed and elapsedtime are fine (checked it with my Garmin 500 EDGE), but TotalAscend and TotalDescend are way off.
I did a flat excercise and got 100/106 meters of Ascend and descend. On my Garmin it was 11/12

Is tis a bug. or am I doing something wrong.

Former Member over 10 years ago

The Ascent and Decent values are read directly from the internal FIT API. I will report this to the device team. It is possible this is a result of the Edge having Barometric Altitude, where the VivoActive only has GPS.

jim_m_58 over 10 years ago

With the va only using GPS for altitude, it can be wildly inaccurate. For example, even with the std run or walk apps, I'll see an elevation change of 400', when in reality, it's more like 40'.

In GC, turning on elevation correction for an activity will give you much better numbers (it uses known elevation for your location). With the fr10 and fr15 (again, GPS Only) GC sets the default for elevation correction to be "enabled", but for some reason, with the va, it defaults to disabled.