I am on my second time through the Phil’s Fondo basic plan (first time with a power meter though). It would be safe to say that I am deep in the “Untrained” Category but the structure has been helpful in keeping me motivated and on track.
That all being said, after yesterday’s Saturday Ride, Training Peaks informed me that I had a new Threshold Power Value. This was 15% higher than the FTP I calculated from the field test at the start of the plan. Which brings me to the question:
Do I FtFP and only modify my FTP and power zones when the plan is over OR do I modify with the new values?
It would be important to look at that training file to see why it is giving you a new FTP. Was it a peak 20 minute power? This is the most likely reason why.
I few reason I can think of: One is that you rode outdoors Saturday and indoors for your field test? That can yield a much higher 20 minute number. Second maybe you did a Zwift race or group ride? The extra motivation you may have pushed it more. A third reason is a different powermeter (trainer, bike or etc) used to measure the ride? And lastly you just are in fact getting better.
Depending on exactly what the reason was I would most likely up your FTP. I would go up by half at least. So instead of the full 15% increase do 7% and see how the first week of training with the new FTP goes. Again you want to make sure your perceived exertion, heart rate and power all falls in line with the effort you are trying to do.
+1 to what Coach @Jake said ^^^^ and also
what was your highest 60 minute normalized power from this ride? Is it greater than FTP? If so then that is at least your new FTP per this training tip:
I think @Jake is on the right path, my FTP field test was under not so great motivational conditions (alone, at night) while I treated my ride on Saturday as a Strava PR hunting ride over segments I know well. I felt strong and very positive throughout the ride, but especially so during the hour which I set this new peak power. Apart from motivation, course, and time of day, most other variables were kept the same.
Following the training tip that @FRANK posted, my peak 60 min average was 168w with a NP of 190w. Both of these numbers are significantly higher than the 145w that I calculated from the 20 min field test. From this I guess my new FTP would be 190w.
Are such gains early on in training unheard of, or is it more likely that the noise in the data is smoothing out?
Your data is telling you, your FTP is at least 190w. I’d raise it to 190 in TP and then the next thing to sleuth out is how hard were you riding during the 60 minutes @ 190w?
If a 6-7 out of 10 , then your FTP is even higher. You don’t know exactly by how much but hat’s the fun part with using your data to keep an eye on your fitness and FTP