Thoughts on intervals.icu data breakdown

@davidtinker Is there a way to filter the Totals page to be for each different sport.
Say I want to look at my zones just for running vs biking?

Yes you can. I added that recently:

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Quick question @davidtinker, avg power for intervals in rides, is that true average power or normalised (basically does it include the zeros). Cause I’m seeing some intervals that just seem like the number I see for avg power looks a bit high.

The default “Avg power” field for intervals excludes zeros. However you can click “Fields” at the bottom of the ride timeline chart and add “Real avg power” if you prefer that:

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Thanks. Thought I was going a little mad!

What makes you think normalized power doesn’t include zeros??

Because it’s based around multiplying numbers to the power of 4, and then taking the root…

0^4 is still 0, so 0’s then have a lot less effect on the averaged power.

Zeros are still being included, though?

ETA: I can see how ICU’s “average power” versus “true average power” could confuse people, though. I don’t know why the first is even offered, much less why it is the default. Flattery will get you users, I guess?

:slight_smile: When you are doing an actual work interval you aren’t likely to have any zeros unless your PM is acting up. When you are between intervals and riding in Z2 then its annoying to have it come up as a Z1 interval because you had to stop at traffic lights and so on. I was riding in Z2 dammit!

Thats why I excluded zeros by default. The power duration curve and so on is always “real average power”, this is just for interval stats.

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If you stopped, you weren’t riding at any level.

How does intervals.icu calculate %s for each of the training methods - polarized, pyramidal, threshold etc? Is there a prescribed % allocation that they give to each training method based on how long you are spending in each zone per week?

It’s based on the ratios between the different time in zones numbers. I got the classifications from FastFitness.tips (Alex) and adapted them a little. Here is a previous post on the topic:

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David, is your figure of “training load” for each activity the same as TSS? The About page mentions using the standard Coggan formula. I’ve some activities where I don’t have a power meter (MTB rides) but the figure is derived from HR data. Just wondering how closely the two were aligned.

Edit. I’ve also got an activity https://intervals.icu/activities/4063918989 that appears in red. What are the triggers for this? I suspect it’s because it’s an endurance ride, 32hrs, and the resulting figures are somewhat off the chart!

If your ride has power and there are no stops and your FTP is the same then training load in Intervals.icu should match TSS elsewhere. There are differences if your ride has stops. Intervals.icu only counts moving time (if available) towards TSS which is different to TP (I have been told anyway). Otherwise sitting around having coffee can make your TSS go up!

For HR only activities Intervals.icu has several models. The default is HRSS (normalised TRIMP) from Elevate. I am not sure how comparable this is whatever TP uses. You can look at rides with power and HR to see what the HR only number would have been.

That activity is tagged as a race so its in red. Rather you than me riding for 32 hrs! :muscle:

This is exactly the max power correction answer I came searching for today.

Still loving the site! eFTP has been very consistent to my real-world FTP testing and I love watching my Fitness score climb higher. That one little wiggly line is more motivating to me than almost anything else in cycling. :smiley:

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That is just wrong. Normalized power is estimating the physiological cost.

Instead of a coffee what about going downhill without pedaling? Or any other break for that matter (e.g. stop lights) - you are recovering and that reduces the physiological cost of the effort. Again normalized power and TSS you are estimating the physiological cost and if power drops to zero then you are reducing the physiological cost and that needs to be accounted in NP and TSS.

This is just wrong :man_shrugging:

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The number I am talking about is average power for an interval, not normalised power.

Thats the point. The way TSS is worked out it goes up if you include coffee stops which doesn’t make sense.

intensity = NP / FTP
TSS = intensity * intensity * hours * 100

So for a ride of 1 hour at 70% of FTP (say 300w): NP = 210w, intensity = 0.7, TSS = 49

Then add on an hour having coffee (and cake!) with your Garmin running:

  • NP = 177w
  • Intensity = 0.59
  • TSS = 70!

Thats the problem with including stops. Intervals.icu does include coasting time but cuts out stops.

This example in the Intervals.icu workout builder:

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Then suggest to the user that the workout gets split into two workouts.

And re: average power, if you take a short break during a work interval then your average power is going to decrease. Changing the average power to exclude short breaks (for any reason) is nothing short of lying to yourself. :man_shrugging:

I get your point but your solution is wrong. Fix your interval detection to deal with the reality of short breaks? It already knows the endpoints with breaks removed. Redefining standard metrics is not the solution IMHO.

I’ve finally got on board the intervals.icu train and wow, what a train! :smiley: Great job @davidtinker !!! :+1:

I’ve been going through and setting up my yearly “seasons” (October 1 - Sept 30th) and marking my races over the years. I noticed that Strava breaks going back about 5 years with my multisport activities all clumped together as a Bike workout so not much use going back into the data beyond that, but I’ve scanned through a couple hundred posts in this thread and I don’t think I saw if there was a solution to this question–is there a way to change the FTP (and maybe HR too) for a given period of time rather than my current FTP staying steady all the way back through the years? I have a record of all my FTP settings through TrainerRoad so it would be easy enough for me to change the dates and have the workouts reflect that FTP setting.

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Tx. You can use the “Edit” option on the calendar page to edit FTP (and W’, weight etc.) for activities for a date range to fix up your history.

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