Xert calculations are incorrect

intervals.icu showed eFTP 249

Workouts I couldn’t complete were these three:

  1. Cheung CX - Ronnestad
  2. SMART - Highway Star
  3. SMART - Uprising+

Athlete type I experimented with few ones. WKO put me as TT, I am stronger on 10m, 20m, 60m power than on 5s 1m power.

HIE/PP fall into upper light yellow line.

My star status fell from 3+ stars to 2+ stars.

My recent Breakthroughs

So it seems Xert is inflating your TP then. If it were me, I’d just reset from the beginning, see what happens.

Makes sense. Nothing to lose really. Will give it one more try. Thanks.

Just refreshed and surprisingly got different numbers (would assume same workouts would be interpreted the same), still too high though 269W, that’s 20W higher than tested FTP.

Your BTs are in short intense efforts, where errors are most likely. I would suggest yo to flag these activities and see what are your new signatures. If you are satisfied try in the future more prolonged intervals if ouwant to test your TP

Which will be based on your latest FTP test.

I do think that Xert finds it hard to reduce TP significantly. It relies on decay methods which can take a long time. If you are then getting new BT’s based on short sharp efforts that is causing the decay not to kick in.
Once your TP is dialled in I am pretty sure it will match your FTP. In fact if I do an FTP test now I use the TP to tell me what to aim for. No massive movements that way but I am sure I can hit that FTP.

Do a full reset or adjust your TP manually and see how you go.

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Are you combining cycling and running power by chance?

I am tinkering now with what to flag so Xert TP matches real FTP. Feels like Xert should be able to interpret that automatically using appropriate model for “high intensity breakthroughs in frequent succession” as that is the whole point of Xert, to be able to determine TP/HIE/PP. Thank you all for suggestions!. Also this doesn’t look correct either.

I did few easy runs a while back which are on Strava, but not sure if Xert picks them up or how it interprets that data

Same thing happened to me. I refreshed more than once and got some wacky numbers each time, all different. The last time I refreshed I got what I think was a close TP estimate, so now I just keep my fingers crossed and leave well enough alone.

Recalculation takes the currently entered (or calculated) values as the value before your first activity, so hitting recalculate over and over will get you more or less useless results.
It should in theory work when you set values that you think might be right at the start of your Xert data, or maybe something below that to give Xert more room to find breakthroughs.

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Actually, what I think I did was completely reset the account, coming in fresh with my Strava activities.

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Xert uses a feedback process - your XSS calculates Training Loads → your Training Loads (using Signature Decay Method and Breakthroughs) calculate your Fitness Signature → your Fitness Signature calculates XSS.

Hence if you start the process off with the wrong values and there aren’t a lot of breakthroughs to bring it back on track, you won’t get great results. Ideally, you should set both your signature and your starting Training Load accurately before doing a recalc. Repeating the exact same thing helps in honing in on the relationship between Training Loads and your Fitness Signature.

Having all this set up properly is a beautiful thing. You can train and track day-to-day progress with great precision. Read our last blog post for additional help.

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In my case there were many breakthroughs from which TP was calculated higher than it should be. I validated that by taking an FTP test after I couldn’t complete prescribed by Xert workouts at TP it calculated.

Which workouts did you try? (edit … up in another post)

Ronnestad is crazy hard. Few can complete that. Highway Star is a bear too. Uprising+ is the easiest of the three but takes a bit of concentration and trusting the dynamic power recovery intervals. If your TP is overestimated by 2%, these workouts can be a lot harder.

Look for workout difficulty to best match your training status. So if you’re at 2 star status, look for 2 diamond difficulty workouts.

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So even switching power sources isn’t recommended.

Spider Chart issue has been reported under this thread (being worked on) –
Ranking Chart Broken - Support - Xert Community Forum (xertonline.com)

Keep in mind TP isn’t the same thing as FTP and while they are close for many cyclists the tests to determine them are different and so are the results.
I don’t think people should try to equate them or more so treat either as a discrete number. :thinking: They are both mathematical constructs and estimates. I consider them as -ish figures. If I get a small bump one way or the other it means my signature is valid (close enough).
Granted TP/FTP values are used for workout goals but Xert’s approach isn’t based on FTP block intervals and that makes a difference. As does their hybrid polarized approach versus SS. As does their strain approach versus TiZ.

So don’t worry about the numbers matching. :slight_smile: A difference from Refresh/Recalculate is normal too. Once your starting signature gets dialed in move forward from there.
Unlike other systems that rely on periodic FTP tests Xert constantly recalculates your fitness signature with every activity and every passing day. The numbers are meant to fluctuate as you reach new fitness levels or decay occurs over time.
In your case the jumps were generated from outdoor rides consisting of shorter intense efforts as @Jomavami points out. Compare that to what happens during a workout designed to generate a BT (search the workout library for “breakthrough”). They are very different than a traditional 20 min test.
Also review the BT best practices article (“the Xert Way”) linked below.

As @xertedbrain notes your star status corresponds to current training load which in turn can determine which workout range is best for you at this time. For example, if you start a progression on Xert at 2 stars then recommended workouts will be in 2 to 2-1/2 diamond range. That is why you couldn’t finish Cheung CX Ronnestad (4-1/2 diamonds) at 100%. The others were 3 diamonds which should have been tough but doable. 95% is pretty darn close in my book. :smiley: All were challenging high intensity workouts best approached when feeling fresh.

If you aren’t preparing for a specific event consider GC Specialist instead of TT as a good starting point. Athlete types (focus duration recommendations) fall into quadrants as shown in this chart –
Athlete type progression - General - Xert Community Forum (xertonline.com)

Training Status and Form – Xert (baronbiosys.com)
Breaking Through the Xert Way! – Xert (baronbiosys.com)
Fitness Improvement and Day-to-day Variation – Xert (baronbiosys.com)
Cheung’s Ronnestad: Fitness – Power versus Repeatability – Xert (baronbiosys.com)

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Appreciate detailed explanation and I have 2 scheduled events so far, gravel grinder in Oct and GFNY 100mile race next May in addition to weekly group rides. I wasn’t sure I could use Xert so I set up ATP plan in TP using traditional plans. I subscribed for a year with Xert and I do want to try more Xert workouts. What would be a good way to know which Xert workout I can substitute for traditional workout? Should I for example search for TT workouts to substitute threshold intervals? Set an event date and just use recommended workout of that day? Is there a podcast or blog about mixing and matching Xert with traditional workouts/plans?