iOS average power

Is the live display of average power in the iOS app correct? It always seems to sit around 200W give or take no matter how I ride.

For example, I just did a ride and at the end, the Xert iOS app said av power was 208W, when uploaded to the site, it was 212W. But Strava (which always seems to be close to wahoo) said 242W.
XEP for the ride was 238W, and the power variability wasn’t that high (238/208).

Also wondering if there’s any plans for a lap function on the app. That’d be super handy for outdoor training.

A bit more investigation reveals there are probably two things going on here.

1.) The iOS app isn’t calculating average power as expected. Even at the start of a ride with consistent power, average power is much different to instantaneous power. I don’t understand how Xert is calculating average power on the app when riding outside.

2.) It seems like stopped time is being included in the average power calculations once a ride is uploaded. So if I stop for a coffee, the average power goes down. Other apps (eg Strava) don’t include this stopped time in the average power calculations, which makes more sense to me. If I ride a time trial at 300W for 1 hour, stop for 1 hour, my level of fatigue doesn’t correspond to an average power of 150W, it’s much closer to 300W. Thoughts on this, should stopped time be included in average power?

Xert models the data differently than other platforms – by design.

Xert Only Counts Elapsed Time - Support - Xert Community Forum (

Ride time v elapsed time from garmin to Xert - Support - Xert Community Forum (

Laps may be coming down the road. :wink:

Showing laps in activities - Support - Xert Community Forum (

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Thanks for the links @ridgerider2
WRT average power including stopped time, I get why they do that. It makes sense for short, high intensity, above TP activities, which is what XERT is focused on so far.
But I’d say for 5+hr rides, where you want to know the max power you can sustain, including stopped time isn’t helpful. If I stop for lunch for an hour in the middle of an Audax ride, I’m not going to be able to increase pace commensurate with the drop in average power (if the stopped time is included).

Would love to see Xert have a go at < TP long ride modeling. For example, if I ride at 75% FTP for 5 hours, what average power can I sustain for the next 3 hours? MPA etc doesn’t help here.
Laps will also be very helpful for pacing for long rides, where MPA doesn’t drop at all.

There’s still an issue with the iOS average power display, that has nothing to do with stopped time.

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