Understanding color markings in zwiftpower...

(Joran Garden [V]) #1


I struggle to understand the parameters an the different colormarkings within zwiftpower.

I can among other things see that my weight is marked red in todays Team ITA ride - even if it comes from a connected Withings Scale…

Can someone please guide me to a manual to better understand what I can read in the “race” table on Zwiftpower?

(Kevin West) #2

Not sure about the other colours, but I’m pretty sure that if your weight is in red that just means that you were the lightest in that particular race - not that there was anything wrong with it.

Numbers also turn red if you have the highest power or w/kg in a particular race.


Edit: Just had a look at that particular race and you weren’t the lightest - so don’t know what was going on there.

(Peter van den Berg WBR(B)) #3

I was also wondering about this. I think for the 95% column, it turns red if you are at/near your FTP. I’m guessing the other w/kg columns are similarly related to FTP though not sure how you would calculate them for the shorter time periods.


What I also can’t figure out are the Avg columns. I thought the one beside 95% (ftp for race I’m guessing?) would be related to that but I see a 50w range over multiple races for the same w/kg.


The other Avg column I thought would be related to Normalized Power but it also doesn’t quit add up (at least for my stats).

(Gerrie Delport) #4

This is my take on the Red highlighted numbers: The highest numbers in each column is highlighted, except for weight there the highest and lowest are highlighted. that make it east to see who put out the most power or weigh the most or had the highest 1 minute power.

Variability Index. A calulation of how even your power was. A lower number is more of a TT effort, while higher suggests many sprints with plenty of rest. It is simply your Normalised power / Average power.
An estimate of the power you could achieve if your power had remained constant.
Avg 20m
If strava data is not available this is calculated from your average power using a modifier percentage based on time of effort


The best place to ask this questions is on the Zwift Power Facebook page. https://www.facebook.com/zwiftpower/


(Dave Whitehouse) #5

I think it’s when you hit a new high in that category 

ie: if your best w/kg is 3.2 and you achieve 3.3 in the event it will show in red as a new high, and I presume the same for the other data columns.

(Chris Tomasini) #6

Joran - I think you’re referring to the NP column of data, and how sometimes there is a red, orange, green, yellow bar going part-way across that rectangular bar containing your np number.

That coloured bit refers to the variability index… how much your power varied during the course of the race.  This page has some info about what a variability index is.

My pretty basic understanding is that you have red in that area when your power level fluctuated widely … so you had a very uneven ride that day. Then the green, yellow, green are various levels taking you down to no colour at all, which is indicating that your variability index is close to zero… so you were doing nearly the same power level for your entire ride.

that’s my understanding anyway!