Hi everyone.

**EDIT: view this before you read anything else** CE101.pdf - Google Drive

I have been in dialogue with @xflintx. We have both acknowledged there have been some communication issues, but by opening a conversation hopefully we have been able to bridge the gap a bit, and for that I am thankful that he indulged me as I dug for more specifics. I will try to put this across in terms that are understandable, with the goal being that the parameters are clear, and we can more accurately feedback, and thus improve.

**What are the parameters used to determine my category?**

**Parameter 1 : Critical Power (CP)**

ZwiftPower calculates FTP from a fixed metric - 95% of your best 20 minute power expressed in W/KG, plus a raw power number to account for lighter riders. Zwift are replacing FTP with Critical Power. Critical Power is a better calculation that takes in to account all of your best efforts from 2 minutes all the way up to 50 minutes. To find out your Critical Power, you could use a tool such as intervals.icu (free) to upload your ride data. Hopefully in the future, your calculated CP will be shown on Zwift so that you can see it and improve it. Note that often this is a lower value than FTP.

This is better than FTP because the ZP FTP calculation relies on a 20 minute full gas effort within a Zwift race, which is generally rare. It also helps to solve the ‘cruiser’ problem because short duration efforts can alter the curve and ultimately your CP.

The Critical Power number will determine your category in exactly the same way as FTP does today. The boundaries are identical, for both W/KG and pure watts. **Note that this is a change from what was communicated yesterday based on feedback**, where it did not account for both w/kg and pure watts. This caused issues for heavier or lighter riders. If this affected you, please leave the race and rejoin. **This change is now live.**

**Parameter 2 – MAP/VO2**

The second parameter that is used aims to account for specific strengths over and above your Critical Power due to how much this matters in your typical Zwift race. It is calculated by looking at your modelled power between 5 minute and 8 minute durations. It takes the Mean Maximal Power (the average max power between these durations) to calculate your MAP (Maximal Aerobic Power). From this an estimate is made of your VO2 max. Note that the thresholds for MAP are currently set at VO2 Max round numbers, but they are designed to be tweaked / altered / experimented with.

**CP Category Boundaries**

A: 4w/kg and 250w CP

B: 3.2w/kg and 200w CP

C: 2.5w/kg and 150w CP

**MAP/VO2 Category Boundaries**

A: 5.4w/kg MAP (60 VO2 Max)

B: 4.1w/kg MAP (50 VO2 Max)

C: 3.9 w/kg MAP (45 VO2 Max)

**Your category is the higher of either the CP cat or the MAP/VO2 cat**

Please ask any questions related directly to this model here, but leave all wider feedback and discussion in the original thread.