[Released December 2022] Critical Power Information in Zwift Profile

Hey folks,

This post is give you more detail on an imminent feature we mentioned in our Competitive November recap post: your power and recommended category information on your Zwift profile.

In about 2 weeks - provided all goes well - we’ll have the first step to more visibility on how your minimum recommended category is being determined. Read on for more detail.

Where can I see my info?

Once released, you’ll find your power information on Zwift web, on both your activity feed and your specific Zwifter profile. This means you can see your information at either The at Home Cycling & Running Virtual Training App or The at Home Cycling & Running Virtual Training App, where “ZWIFTID” is your ID. The second is accessible via the “My Profile” button on the top right of your information in the activity feed, as shown below.

This will be in English first, with localization to follow shortly after.

Neither the activity feed nor your profile are publicly visible to anyone. You are the only one that can see your power information.

Initially, this information will exist only on Zwift Web. We will then have the information available on Zwift Companion in the future.

We will not be integrating this information into ZwiftPower due to technical considerations, so there will be still be some discrepancy between your Zwift category and your ZwiftPower category as there is today.

What will I see?

You will now be able to see the following information on your Zwift profile, in order from top to bottom:

  • Suggested minimum category - the lowest minimum category you can join for a Zwift race with Category Enforcement enabled
  • zFTP - our best estimation of your FTP based on your data
  • zMAP - our best estimation of your MAP based on your data
  • VO2max - our best estimation of your VO2 max based on your data
  • Critical Power - your best recorded critical power values for a given interval of time in Zwift, starting at 5 sec and extending to 30 min. Keep in mind these are not the sole values we use, merely what we found most relevant to display to Zwifters in the first iteration.

Here is an example screenshot:


All numbers in this screenshot are not from a real profile, and are made up solely to provide a visual example.

When you click on “More Info” you will see a more detailed explanation of the information on your profile, as shown in the below screenshot. You will also see what date and time your critical power values were registered, helping you pinpoint the activity should you need or want to.


All numbers in this screenshot are not from a real profile, and are made up solely to provide a visual example.

If your chosen gender in Zwift is female, you will also see the information specific to the women’s categories in addition the non-women’s categories.


All numbers in this screenshot are not from a real profile, and are made up solely to provide a visual example.

What is used to determine the numbers I see?

We record every activity you do on Zwift on a 60 day rolling window, even if you don’t save the activity or the activity is deleted. That means that every time you ride on Zwift, whether it’s a workout, race, group ride, free ride, or anything else, we record your power to get the most accurate profile of you as a rider. This is then used to determine the above points (minimum category, FTP, VO2, MAP, and critical power). We do not use ZwiftPower calculations, though they are close to one another.

For a more detailed breakdown, check out this article on our support site.

If you have an activity that you feel is causing your power information and category to skew too high, please contact our support staff.

The Release Plan

We will be releasing this information according to the following plan:

  • Step 1: On Zwift web in about 2 weeks - as mentioned above - on both your activity feed and your specific Zwifter profile. This means you can see your information at either The at Home Cycling & Running Virtual Training App or The at Home Cycling & Running Virtual Training App, where “ZWIFTID” is your ID. The second is accessible via the “My Profile” button on the top right of your information in the activity feed, as shown below. This will be in English first, with localization to follow shortly after.

  • Step 2: Following the web release, Zwift Companion will also have your power information, located on your Zwift profile page. We will have more information on this in the coming weeks, as we’re currently working through the designs.

  • We will not be updating ZwiftPower with the same information due to technical considerations.

If you have questions or feedback, let us know in the comments below.

We’ll be locking this thread in 14 days to keep feedback pertinent to this update.

33 Likes

Looks really good Flint - thanks.

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Nice one. What is used to determine your category, CP or FTP?

If CP, is it CP20 from that list?

Also how is zFTP calculated if it is higher than CP20? Or are they just dummy numbers?

Critical power and MAP/VO2. The FTP acts in the same way it does on ZwiftPower: as an additional threshold to meet to account for weight etc.

The FTP is calculated based on the CP/W` formula, which uses a few different values plus a linear regression to find the line of best fit. We don’t use one single time interval to determine the FTP.

The Critical Power values we show are to help you understand the curve, and not explicitly linked to the FTP we give.

What we use to determine category are the FTP, MAP and VO2 values.

1 Like

OK, but CP isn’t shown? Or is it the CP20 value?

I may have missed the memo but CE measures from 2min-50min so why not show numbers for that range instead 5sec - 30mins?

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This is cool. Really wish the CE category info also showed up in ZP because there will still be confusion when people conflate the ZP and CE categories if they mainly look in ZP. I imagine the technical issues relate to not wanting to risk breaking something in ZP therefore there’s a desire to not muck with that code too much, but hopefully eventually some updates can be made to ZP if Zwift plans to continue supporting it.

That looks good but CE use CP and MAP/VO2 values as Category boundaries. I would expect to see a single CP value that is used in the category boundary limits.

Looking at that data there is still no way of knowing in what category the rider should be.

image

Not that it makes any difference because the Suggested category is shown, but I thought the point of showing the data is so that people can see where in the spectrum they lie.

Is this the FTP of the last 60 days?

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Edited my response above. Realized I misunderstood when attempting to answer originally.

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Everything is in the last 60 days and from all activities.

Great callout Gerrie. We’re getting the information, which is a great step, but now we need to marry it up with the boundaries. Represent them visually and boom, it’s clear why you’re recommended an “A” instead of “B”.

Something like this (apologies for the quick and dirty mockup):

Get us that and you’ll never get a “why am I in X Category” ever again :slight_smile:

26 Likes

sweet. thanks

OK got ya. It’s going to be important to get this clear on the tables that show where you fit (or a graphic like shown above). I’m not sure I’ve ever seen FTP calculated from CP before. Seems a bit counter-intuitive but will go with it for now.

BTW if us few are feeling confused, I’d be a little worried…

2 Likes

i wouldn’t mind knowing how vo2 is derived. but as long as i have something i can point people towards and say “these are my actual numbers” i guess i dont really care.

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Maybe this is a better way of asking the question.

Is zFTP actually your calculated CP?

Using the CP/W` formula, yes.

That’s not quite what I asked.

Is zFTP your calculated CP?

CP is a singular output.

In the support article you linked above it shows CP as the delimiter. Is zFTP the new terminology for CP?

I’m not trying to catch you out by the way, but it’s probably important you at least know the answer even if I don’t!

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This would be so much less convoluted using Compound Score (5mins pure Watts x W/Kg), ageeing score pen boundaries, agreeing rolling evaluation period, no minimum Watts so all five pens used by all ages and genders according to ability.

One figure, clear boundaries, everyone knows where they stand.

4 Likes

Hi @Steve_Clowes www.zwiftracing.app :wink:

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seems like they just consider FTP and long duration CP the same thing if i had to guess. they are certainly using coggan’s definition of “roughly an hour” which is 40mins+, a factoid i discovered from an obscure forum post he made on a forum nobody reads.

2 Likes