I tried doing the guided FTP-test on my watch, using a Tacx Neo as the power source. I Neatly followed the ramp-up (4 steps of 4 minutes, one of 3, and 2 minutes all out). The 3 minute step was the first one above the FTP-value I use in regular interval training, so I thought everything was going well. I hit all the targets nicely, got my heart rate above what I believe is my threshold, and kept my cadence pretty even throughout. However, at the end of the protocol, the watch said: "No FTP detected"
I noticed that halfway through the 3rd step (where the target range was 325-345W) my 'performance condition' suddenly fell to zero, after steadily climbing from 4 to 9 throughout the session. It stayed at zero through the remainder of the training, which I can't help but find very odd. I repeated the test later on, and pretty much the same thing happened - no FTP detected, and dropout of performancew condition halfway through. Could the two be related, since both are calculated with firstbeat's analytics and rely on the VO2max-setting in my watch (as far as I can understand)?