I have a new power meter on my MTB, (Stages XT dual sided) and recorded some rides with it now.
I love having the power data when i’m on my MTB but the data between Garmin and TR/Strava/others isn’t the same. (recorded on a Edge 530)
The AVG power and thereby the NP, TSS, IF and KCAL’s are different between the platforms.
This is my ride from yesterday on different platforms:
Garmin Connect give me an AVG of 256 and the others reported a average of 234/235.
Looked at this with an TR engineer (great help as always!!), and they noticed that the FIT file contains more data that TR/Strava does take into account and Garmin does not.
I’ve created an export of the record that contains 5852 rows, i’m getting the avg power of 256, but including all the other records i’m getting the average of 234/235.
I have submitted a ticket to Garmin but maybe someone here knows why Garmin isn’t including all the data to get to the Average/NP etc. Kind of frustrating not to know what is the “real” data here.
Settings from my Garmin:
Auto pause on
Include 0’s in power = on
Include 0’s in cadans = off
I’ve created a smaller test yesterday and still having the same issue with Auto pause off and with 1 second recording (setting was always on 1 second recording).
Went digging and i can see that Garmin isn’t including all the data sets when calculating the averages. But cant find a explanation/reason why this is happening. If i include all the timestamp’s into a single file. The averages are the same across the board. But GC isnt doing this… UGH!
@GPLama
Think we’ve found the answer to this problem.
“Incorrect average lap power - Edge 1030 Plus - Cycling - Garmin Forums”
“So this gets a little complicated, but the difference is due to a couple of things going on. One is that there are radio outages that are causing some of the records to be back filled. The second is that the tools you are using to process the data are using the power values assigned to each record and are not using the accumulated power values. Using the accumulated power values is the better approach. Because of this the tools are subject to how the dropped messages are being backed filled.”
So if there is a missing data point, Garmin know’s this because of the accumulated power values and corrects this in the averages. TR and other platforms only look at the raw power data without taking into account the accumulated power values. So it’s actually Garmin who knows "best’.