Automatic FTP after manually changing it

(Jason Chu chu) #1

Hi team, I have never taken either of the FTP tests and I also don’t know what my FTP really is… but a few weeks ago I decided to increase the difficulty of my workouts by dragging that line up so that it makes all the wattage requirements higher. I now understand that what I was actually doing was increasing my FTP number (currently at 255).

This is fine. The difficulty is moderate. But I want to know whether Zwift will go back to automatically changing my FTP if I reach an improvement? Or am I stuck now with manually changing my own FTP?

I’ve also started the Zwift Academy, and I’ve been nailing the workouts so far … I would have thought I’d be due for an increase, which is my next question, how often does Zwift change your FTP?


(Joe Daknis) #2

Zwift doesn’t change your FTP unless you either a) take one of the two FTP tests (standard or ‘shorter’) in the workout menu or b) have a 20 min effort with average power that is significantly better than your current FTP setting.*

*it’s not quite that simple, really.  Your FTP in Zwift is 0.95 x your average power over the 20 min test interval.  So, if your FTP is currently set at 255W? That won’t change unless you put out something > 270W (average) for at least 20 minutes.

That said, if the difficulty is ‘moderate’ with your FTP arbitrarily set at 255W? Take a test. 

 If you’re on a smart trainer and doing workouts in ERG mode, you’ll never get the most from your workouts if your FTP is set too low - and the easiest way to know for sure is to test yourself. 

Or, try something like this:

If get through all 6 @ 120% of FTP and the difficulty is just ‘meh’? Your FTP is definitely set too low.  

(Jason Chu chu) #3

Sorry, by automatic I mean give me the pop-up to tell me “we’ve detected an FTP increase from X to Y”.

Ok perfect, that formula is what I really needed to know. I am not sure that I can output 255w for 20mins straight so it’s probably set ok. I can do the workouts (don’t get me wrong, a few are hard) but none of them need me to hold 255w for 20 mins so that explains why.

I don’t have ERG mode.

I’ll take a test after the Academy is over.

Cheers mate.

(. #darth.rider..) #4

Hey Jason - I’ve pretty much only done workplans since getting onto Zwift 3 months ago with probably no more than 3-4 non plan rides.

Not knowing how to use Zwift properly, after a couple of weeks, I had a “your FTP has changed” messages.  Think that was my first race.

Then it happened again after another race about a month later.

Last week, after almost 3 months of being on a plan, I thought it was time to see if my fitness was improving by doing a casual ride up one of the bigger climbs - to see how much power I could consistently push out up the climb (it was about 35min climb for memory).  At the end of the ride when saving to Strava, my FTP increased again. I have no doubts that if I were to take an FTP test at that time, I would have got the same result.


I havent done an FTP test yet.