FTP decreased



i have been using Zwift for 4 weeks now, regularly participating in group events - initially I did an ftp test which came out at 114 (returning cycling after a long time off), I did another one a few days ago to see how I had improved and it had decreased to 111! 

The group event I did today was far to easy and I’m wondering what’s gone wrong? 


Any pointers or suggestion would be good.



Hi Kellie,

It looks like you are using a Tacx Flux. Is your trainer up to date with the latest firmware, and have you done a calibration? It’s generally a good idea to keep the firmware updated, and do a calibration time to time. 


Hi Josie

Yes it is all up to date - maybe I’ll do another FTP test after a few days of rest ? Only thing I can think of doing!

Hi Kellie,

Just to reinforce what Josie L. suggested, if you’ve been on Zwift for a month your trainer really needs to be calibrated.

Many people think of calibration with regard to devices as a one-time thing or at least once in a great while.  With trainers it’s not.  Depending on how often you ride and some other variables you may need to do it more often, but I never suggest going longer than a month without calibrating.

I Zwift usually every day and the best way I’ve found personally to calibrate is to perform it AFTER I ride.  I calibrate every week on Wednesday so even if it gets slightly out of calibration it’s not enough to throw off any test, workout or race I’m doing.

I perform the calibration after the ride because the trainer is good and “warmed up” to my usual intensity level and it’s much more convenient for me than warming it up for 20 minutes before my ride.

Best of luck!


I’ll try calibrating after my next ride then :) 

I manually increased the ftp today by 5 and the ride was better - a lot of people saying oowwwiie, but I found it ok hehe