Giro got me thinking…

Watching the Giro I am curious how much XSS would a stage actually be and roughly speaking what is the maximum XSS you can accrue in a single ride (aware technically unlimited if you keep going so more realistically in the context of extreme events like a classics race or ultra endurance event)

Related to that, does Xert ‘pick-up’ your genetic limit?
Using the goal mode I’ve often found that even giving 28 hours a week (I.e. well into territory of a pro who’d have good recovery too to fit it in) for a year has some goals as unattainable.
Does it just need more than a year (it seems to bug out for anything around or beyond the year mark at the moment) or does the curve the model produces estimate your ceiling?

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I did an ultra a couple of weeks ago. It was 837km with ~13,000m climbing.


1415XSS says Xert!

I’m sure it’s possible to go for longer, so then the question is what’s the end of a ride? Sleep perhaps?

Worth noting that I needed a few days off after this, so once you start averging out, an ultra isn’t that great for fitness building!


Yeah, I’d agree that sleep or a significant break is the cut-off. Completely arbitrary but the defining feature for me would be “If I had normal shoes/clothes available would I change into them and bike into riding gear for the next part”

If yes, its a new activity.

Here’s analysis of MVPD 1st place finish at the 2019 Amstel Gold Race. It was rated as Tough Mixed Rouleur Ride with a total XSS of 485 XSS.

  • Notice that overall difficulty score is quite low for the first 5 1/2 hours (about ~75)
  • Carb burn estimate was ~1026 carbs in 6 hrs (~171 g/hr, which is reasonable assuming that most pro’s are replacing about ~120-130g/hr)

Somewhat, yes. We know what your historical training load(s) are & what your signature was at those times. From that, we can calculate your training responsiveness

Xert assumes that your fitness (TP, HIE, PP) will increase linearly with each respective training load (Low, High, & Peak, respectively). Ultimately time is the limiter for every athlete… there simply isn’t enough time to ride (and recover) to build your training load high enough to achieve certain signatures (unless your untrained/base signature is sufficiently high, e.g. you are genetically gifted :slight_smile: )

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1 Kg carbs, crazy!

How did you estimate his signature?
Did he publish his TP/PP and you assumed HIE from PP?

With the power data from that single activity! It was a breakthrough effort :slight_smile:

For a high untrained base/genetic background piece I’m guessing the time also works if you have an exceptional training responsiveness where you basically just have to look at a bike and your fitness improves.

Always good seeing these things and understanding how it works, and that your 600 xss ride was ‘equivalent’ to a pro race (for your limited fitness)

Also helps me work out where my data may be wrong. I’ve generally always been on a zone 2 program for most my historical data with very rare true “failure” efforts so I’d take it that means be responsiveness may be a touch off but will correct with more BTs

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I think this is really important and something that makes MPA analysis really interesting/unique!

“Zone 2” isn’t bad, but it’s important to combine it with high intensity efforts as well! But you’re exactly right… as Xert has more ‘true’ maximal efforts to analyze, the Training Responsiveness estimations will likely improve & the need for all-out efforts will decrease, since your parameters will track with their training loads more accurately.

I’ve been on ‘Slow’ Decay for some time now and my last BT was ~11 months ago :sweat_smile: Maybe it’s time to try for one? Regardless, I’ve seen a significant improvement in my estimated TP this winter just from the training responsiveness accounting for my increase in TL over the last few months.