Fitness Signature & Peak power

My peak power was set to ~1600w in Xert, and an tp of 230 - but I don’t have the ability to go that high. I have looked at my Garmin 5s, 10s and 20s best ever values and used that to fix my fitness signature.

Now my peak power is around ~830 with an tp of 266. Does that makes sense ? is this the proper way to fix the fitness signature?
I don’t really understand why the peak power was set that high. I have no ride with errors that would have produced this.


Hi Tarek,

You don’t want to use your best every power values to set your fitness signature. Instead, you should use current MMP data (within the past 1 month or so), since your fitness signature is meant to tell you what you can do right now, not your best ever. Also, remember that Xert is telling you what the highest possible power duration that we expect you to be able to generate, not the highest power that you have generated over a given amount of time (that is easy and can be done by most software platforms). Hope this helps!

Hi Scott,

Well, so looking at my current MMP data in most rides, the near peak power is quite low simply because I have never tried to do few seconds sprints. what could be a good way for me to set the signature to something closer to reality with the data I have (simple rides, but with some hills intensity up to 10/20mn) ?
Maybe using 5mn/10mn/20mn powers from the MMP ? My 20mn best effort is around 4.3w/kg, I am not sure how that translates…

Also, when you say “Xert is telling you what the highest possible power duration that we expect you to be able to generate, not the highest power that you have generated over a given amount of time” - I am still confused at how it would possibly predict 1600w as peak power, that’s why I tried to correct it. Now maybe I should just leave it alone at 1600w ? Could it be possible that imported runs affected the algorithm ?

Thank you!

I have removed all my runs manually and I have 39 rides in the system now. I was not sure how to reset the fitness signature values to let xert find it by itself, but by leaving all field blanks and hitting “recalculate progression” seems to work (if there’s a specific way to reset the fitness values, let me know please). It looks like I have something closer to reality now - it finds 793w as peak power, and a TP of 262w, which is what strava and garmin gives me for my FTP. I guess I’ll watch and see how things evolve from there. thanks

Yes, at this time you should only sync rides to your account, since the PD curves for running and cycling are different. Be sure to set up activity filters with Strava or Garmin Connect to only sync in your rides. HTH

Not to dig up an old thread, but having the same issue so figured I’d post here for others searching. I had a bad / miscalibrated power meter and was obliviously syncing these rides. Now looking to use Xert again for some focused training and the peak power numbers are way off (too high). I went back and flagged a bunch of rides that seemed to have been the culprits, but it’s still too high (I’m not sure flagging caused it to even recalculate?). What’s the easiest way to just recalibrate? Is there an easy way to just clean the slate and start syncing fresh?

Edit: ok, I answered half my question – select all and delete seems to work well from the “Table” view. I guess my other half of the question is whether flagging a ride should fix the calculations? And how you can tell which rides were really throwing it off?

Edit 2: Ok, despite deleting everything, Xert still thinks my peak power is 1670w, which is … just a tad … higher … than it should be :slight_smile:

See: Is PP a theoretical number? - General - Xert Community Forum (

You can recalculate your entire activity history (Account Settings, Profile, Recalculate Progression), but that isn’t normally recommended if your signature is close already and you’ve been flagging suspect records. Flagging excludes activities from signature calculation but retains the overall XSS values to determine training load and focus.

Thanks; this is very helpful!