# Yet another baffling data discrepancy (Bolt / TrainingPeaks)

**URL:** <https://www.trainerroad.com/forum/t/yet-another-baffling-data-discrepancy-bolt-trainingpeaks/15267>\
**Category:** Equipment\
**Created:** [April 29, 2019, 4:53pm UTC](https://www.trainerroad.com/forum/t/yet-another-baffling-data-discrepancy-bolt-trainingpeaks/15267 "2019-04-29T16:53:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![martinheadon](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/martinheadon/32/7705_2.png) [@martinheadon](https://www.trainerroad.com/forum/u/martinheadon)\
**Post date:** [April 29, 2019, 4:53pm UTC](https://www.trainerroad.com/forum/t/yet-another-baffling-data-discrepancy-bolt-trainingpeaks/15267/1 "2019-04-29T16:53:00Z")

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To add to a couple of similarly-themed but different threads, I thought I’d add my recent odd experience.

I went on a 4 hour ride on Sunday. Afterwards, when uploading to TrainingPeaks, it said that average watts were 174 and Kj were 2682. Which can’t be right, as 174 x 4 x 3.6 (the standard watts to kj calculation) is 2505.

Then it gets weird. I deleted the first 5 seconds, and only the first 5 seconds, of the workout data. The Kj stayed the same at 2682, NP the same, but the average watts suddenly changed to 185. Which x 4 x 3.6 = 2664; so basically matching. See screenshots below.

God knows what’s going on. I’ve submitted a help ticket to Wahoo, because it seems that there’s a possibility it could be regularly giving me understated average watts.

 ![09](https://global.discourse-cdn.com/trainerroad/original/2X/2/2dd10a00940740aad6fb394ce380e661382b867b.png) ![14](https://global.discourse-cdn.com/trainerroad/original/2X/6/63133212a5379fa1d4fed3e2725b9a5812f6ffed.png)

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**Author:** ![mcalista](https://sea2.discourse-cdn.com/trainerroad/forum/user_avatar/www.trainerroad.com/mcalista/32/92377_2.png) [@mcalista](https://www.trainerroad.com/forum/u/mcalista)\
**Post date:** [April 29, 2019, 11:16pm UTC](https://www.trainerroad.com/forum/t/yet-another-baffling-data-discrepancy-bolt-trainingpeaks/15267/2 "2019-04-29T23:16:24Z")

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I’m seeing a big change in elevation as well from cutting those 5 seconds. Which suggests to me that there may be something going on as the device calibrates the altimeter as you start. (I’m a Garmin rather than a Bolt user, so I’m not sure what method Wahoo use to do this).