Polarization Index added

Thx, David,
That explains my commutes without data info.
But what about the race in the clips below? There is a fair distribution across the power zones but no PI-score.
Morten


Thanks David. The rides with 0.00 against PI are either recovery or Zone 2 rides, so that’s fine. What was confusing me, having thought about it further, was that I was l looking for a PI heading in the summary of all rides but then realised that while the number always reflects the PI rating, the name/ heading could be Threshold, Pyramidal, etc.
Is there a way to get a PI figure for a week, or a month? Thanks, again, for all you put into this great resource.

You can in the charts, but it all depends what you want the data to show. This is just an example of PI vs RPE per week and per month, as well as PI per week/month with the moving average. This is a test only, and no significant meaning to want to use it. It all depends what you want to get out of the data.


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Gerald - that’s really helpful, thank you. I’m also using bar charts of weekly time in Zones 1&2, 3, and 4>, which gives me a good sense of the overall percentage split of my riding time. Thanks again for being so responsive.

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I just had a look at the formula and it will return “null” (cannot be calculated) if there is no time in S3 or time in S3 > time in S1. This is using the 3 zone model (S1 = Z1+Z2, S2 = Z3+Z4, S3 = Z5+). As you can see that is why your 17th September race has no PI:

Screenshot 2023-09-29 at 17.41.32

As to why it is like this you need to have a look at the paper:

The PI for your training zone distribution for each week is shown on the calendar and in the popup when you click that:

Screenshot 2023-09-29 at 17.45.12

You can see PI for any time period on the /totals page.

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Very helpful David, thank you. I also use the 3 Zone/ Seiler model, though I find it helpful to group zones 1&2 as Z1, 3 as Z2, and 4&5 as Z3. For each workout I can look - thanks to what you’ve built - at how much time I’ve spent above various heart rates; having weekly totals on time in (my) 3 zones on the Fitness page gives me a good overview of how my training breaks down. Thanks again for providing us with such a great tool.

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Adrian,
Could you kindly post a screen shot of how this looks in your setup of intervals.icu? I am looking to do exactly that, ascribing to the 80/20-training philosophy. So I would like to monitor that I am not drifting into too much sweet spot training.
Morten

Thanks for this. I’ve been using clunky charts to track this. But a few things stand out:

  1. I really think S3 should include Zone 4, or any threshold / FTP work, because those workouts occur at or above LT2, which the paper notes is the line between S2 and 3. Because these things are spectrums, the line has to be somewhere, and because workouts at FTP/threshold will always cross and remain above that line, then they should be listed as S3 in a polarised model. I read the paper for its physiology content, and I noted that they presume this everywhere, but yet in the second paragraph of the introduction casually toss “threshold” into S2, which is not reflective of Seiler’s et al. who place FTP/threshold work at LT2 and above because these workouts do indeed aim at or above the LT2 line (unless I and many others are missing something important, which is entirely possible).

  2. It may be misleading to mark a given workout as polarised or not. No single workout can be polarised, the workout trend can be polarised, and single workouts (low, med, high intensity) contribute to the nature of that trend. Each workout will regularly touch on all zones, but for polarisation purposes, the workout is defined by the main goal/dominant performance. An example is 5 X FTP-VO2 hill repeats followed by a long slow ride home, will still only be an S3 workout, even though there may be an hour or more of S1. In that case, it will look polarised as a single workout, but that info has no value at all in following a polarised training model.

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Morten - sure. Please see the attached. Essentially I created a Custom Chart with 3 plots on the Y axis for time in Z1&Z2, Z3 and Z4+. I use weekly totals and bars for these. I’ve added an overlay plot of my fitness, with a line. When you create the custom chart all of these variables appear in a drop down list when you click on “Add Plot”. Let me know if any of this doesn’t make sense. Adrian

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I should have added that how you set your HR zones in Settings is important. I have my Zone 4 starting at approx 90% of max HR and am happy to consider any minutes spent in Zones 4 or 5 as ‘hard’ (aka 20% in Seiler terms) in comparison to rides and workouts in Zone 2 (his 80%). I decide what kind of workout to do to achieve time spent working ‘hard’, differentiating between VO2 (Z5>) and Threshold (Z4) workouts according to time of year, how I feel, etc. Hope this helps.

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Please stop telling things that have never been said by Seiler as if it were the absolute truth.
Check this video at exactly 39min in.

It might even be surprising for a lot of people that already know some of Seiler’s work. Z2 is no longer the NOGO zone and you are left with only 2 session types: EASY or HARD. That’s it. Perfect system for any beginner, easy to follow and almost no risk of burning out, yet efficient.

I don’t care where this ‘Polarized Index’ thing is going but don’t make it look like it comes from Seiler because it absolutely isn’t what he’s saying.
All he ever mentioned regarding TIZ was when he was asked how it related to TIZ during an interview. The answer was: I don’t know exactly because I never looked at the statistics that way, but it’s probably more going to be like 90-10% or even lower HIT.

I don’t have any problem with the fact that you want to do things like you are doing them now. If it works for you, fine. But then just call it your own system and don’t make it look like it comes from a renowned researcher.
You are giving wrong information to people looking for a way to workout with an efficient system. Lots of them are beginners and they have no idea yet where to get correct information.

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Thanks for sharing that video, which I’ve watched several times but many may not have. I was responding to a request from Morten and I think I made it pretty clear (repeated use of ‘I’) that it’s a system which works for me, based on my understanding of multiple articles/ podcasts/ videos by Seiler and others. No claims to absolute truth by me.

Fair enough. It was only the part that I quoted that was upsetting me.

I don’t see any polarised index in my activity summery?

I had a look at your Thursday ride and it is there:

Screenshot 2023-10-20 at 06.55.10

Is there a way to graph the PI for the whole week? Not the total PI of the activities for the week. I would think it is a better guide to know how close I was to “2” for the whole week, than have “18, 20 or 21” PI as a total for the week.

As the week summary in the activities page shows.

Thanks in advance
Screenshot 2024-01-22 11.06.11 AM

Unfortunately you can’t do that at the moment.

I’ve gotten a negative value for the weekly polarization index twice the last month. I thought 0 was the lowest value one gould get. Is this a bug?

It can be negative. The calculation includes Math.log10(t) where t is a number derived from the relative time in the 3 zones. If t is less than 1 then the result will be negative.

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Ok, thank you. I actually looked at the cited article to check how the value is calculated but since my math skills are rather poor (log10(t) :crazy_face:) I couldn’t understand if a negative value is possible.