Incorrect fitness signature


I would like to understand if there are any inconsistencies with my fitness signature and if so how to resolve them.
Since I stopped for two months (August / September) I gradually started training again to get back in shape.
I have never touched the decay method of the fitness signature, but I think at the moment my TP is underestimated, every time I go out, quite easily I get a BT, also my LTP is very low while the HIE is perhaps too high.
Can you help me to correct and give me some advice on what to do next time I go to the off-season?
thanks a lot

Correcting is easy - just do a hard breakthrough effort. HIE decays faster than TP so the fact that you’ve allowed the decay shouldn’t cause an overstatement of HIE / understated TP, or other issues

Re: next time, wouldn’t say you did anything wrong but an alternative is to set your decay method to ‘no decay - training load matched’ when you are in an off season or base phase. Then your signature only goes down due too falling training load (and up when you restart), with no additional ‘decay’

Hi Wes,

thanks for the advice.
I made an effort to get a BT successfully, the TP increased so did the hie while there was no change in the PP.
I am attaching two images, the first summary of last year variations in fitness signature, the second relating to the XPMC of the last 3 months, just to give an idea of why I asked this question and still continue to be a bit confused

From that section it doesn’t look unreasonable as threshold and HIE increased along with training load in that period. Maybe show the full 12 months to see if anything odd happened with the decay…?

It’s normal for LTP to go down a bit when HIE increases, which can be driven by the type of training you do

What kind of training and focus have you had / is it aimed at high intensity? You can add focus to the progression chart, and also add lines for the different training loads (low, high, peak) to the signatures chart to see whether they track signature development as well

This article has a table where you can check normal ranges for HIE vs Peak power

Assuming peak power is correct, your HIE could be a bit high after the last BT, in which case you could manually adjust it. Again depends whether your recent training has been targeting HIE. Or if you think peak power is too low (eg it’s from a sprint on the trainer, which are typically lower) then it may still be ok

Thanks for the replies,
during off season every parameter went obviously down, when i started to train again HIE is pointing up very high above last year’s starting point and is still going up.
I’m doing outdoor BTs while on the trainer i just make suggested workouts according to time i can spend on the trainer that day. Bbut i never tried to make a BT on trainer, while when i go outdoor i aim for BTs and can reach the point “almost” easily. That’s why i assume there is something wrong and maybe indoor workout intensities are too “low”.

If each BT is almost easy, you should try for a big BT… I mean breaking through by a lot… don’t stop till you really can’t put out any power above TP… even get out of the saddle and sprint all out at the end… sounds like so far you’ve not pushed yourself fully, hence the signature would be low. By definition the next BT should then be very tough to achieve.

As an aside, apparently if you stop your BT effort suddenly (eg at the top of a hill, or just because you’ve reached BT and feel like easing up) rather than going through failure, the signature can be out… it looks at the shape of the power drop off… my rationalization (they may correct me!) is that it thinks if you stop suddenly it’s from suddenly running out of power, and doing so quickly is more typical of someone relying on anaerobic capacity and fading quickly (HIE) than endurance fading slowly (TP).

If you’re worried about the shape / relativity between parameters, you can also send an email to the support team and they’ll take a look - usually fairly quickly.

It may help to review this article as BTs can occur anytime even during indoor workouts that are not necessarily designed to generate one. :slight_smile:
Breaking Through the Xert Way! – Xert (

XATA won’t recommend a BT workout specifically but warns you when your signature is stale (no changes in X weeks). You’ll want to manually select an indoor BT workout when this happens if you don’t have any high intensity rides/workouts planned.
As @wescaine mentions once your signature is dialed in subsequent BT’s are harder to obtain.

Technically you can throw a BT-style effort into any indoor workout by switching to slope mode, ignore target watts, hammer until you’re ready to drop (draw MPA down watching the rainbow gauge), then add a 5-7sec out-of-the-saddle sprint at highest spin you can maintain.

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