Why does average power calculate differently between services?

I’ve been experiencing this as well. What I’ve noticed is that my average power on the bolt will be comparable to my normalized power in strava and TR.


What PM are you using?

What is moving time/total time in wahoo app?

It looks like you have exluded zeros from power averaging.

Hi Daniebr,

I never responded but this is my setting and always had been

Is there something I’m missing? I can’t find anything else that looks relevant

Looks right.
What PM are you using?
You can check by calculating: KJOULES/TIME = average power. Just keep in mind that different services uses different time, see: Why does average power calculate differently between services?

Powertap chainring.

When I do the kj and time calc for a strava ride it matches exactly. Wahoo isn’t close

I took a sample of rides to compare all the platforms. Here’s a screen grap

Ignoring NP as they’re calculated differently but for AP a watt or two here or there between strava, TR and intervals but wahoo is always a way off

Very frustrating

Having got this far I am going to raise a ticket and see where it gets too. Probably nowhere but the more people about then the better I suppose

Using a wahoo bolt.
I do have zeros excluded on wahoo and strava.
Moving time is
2:25:44
Total time is
2:27:31
Paused for 1:47

You should never have zeros excluded from power IMO. I don’t even know why they offer it as a setting.

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I’ll switch and see what happens.

Ditto, another option that I despise. It leads to poor data in any event that it is enabled. Just plain bad.

So I raised a ticket and fair enough they responded pretty quickly as follows…

"Hi Sam,

Thanks for sending over those .fit files. My apologies for the delay in replying.

I have spoken to our software team, they have said that these results are well within the expected differences due to slightly different algorithms used between platforms. For reference, we use the same algorithm as TrainingPeaks, so you’ll see identical power averages if you load a .fit file from your ELEMNT device into TrainingPeaks"

So I thought I’d try it and true enough the two workouts came out with the same AvgP in trainingpeaks as wahoo.

So the next question is… Do other people see significant discrepancies between trainingpeaks and TR / strava? Aside from maybe small differences in autopause calculations I can’t see that an average power algorithm has much wriggle room? Sampling issue maybe?

I don’t see it often, but here is one of my workout comments from December 5:

“And 5-sec power was 993W so not too shabby - oddly TP says 968W but WKO, Garmin, and TR say 993W.”

FWIW I turned off auto-pause a long time ago.

I know WKO4 report status based on fixed gaps in recording. Is your Training Peaks synchronized from WKO or pushed to WKO? I would guess pushed to WKO. I’m surprised that TR didn’t report based on the raw file. My experience is TR just report based on the data file uploaded unless it’s doing the recording where it will correct the gaps. Have you examined the raw file from each application?

If you are asking me, ride data recorded on Garmin and sent to TrainingPeaks/TrainerRoad/Strava. Then TP sends same raw data to WKO5.

I reviewed the raw data around the 5-sec sprint, and it’s identical on TP/WKO5 and appears the same on TR (no raw data access).

It’s a mystery. Been meaning to file a support request with TP… Filed support ticket with TP on 18 January 2021.

Trainingpeaks will just present average power as calculated by Wahoo Bolt:

You can select the whole ride in TP, and then TP will calculate a new (and correct) average power:

Did anyone resolve this? I still have the same problem using a Quarq PM. So frustrating.

Interesting. I can see/note very slightly different average powers from Strava, TR, and my Elemnt Roam. That said, the differences are usually so small as to have no practical consequence. What can be annoying, though, is significant discrepancies between max power readings over 5-10 seconds. It is irritating to look down at your head unit and see a PB, only for the Wahoo data file somehow to ‘miss’ it and subsequently record a max value 20-50w lower!

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but as far as I know WKO5 does not modify any data and receives from TP as it is.

My WKO4 automatically fix gaps in the data but doesn’t overwrite the raw data. Can’t find if there’s a flag to change the behavior. I’m surprised that WKO5 did a 180.