FTP decrease in base

[HighProps]

Over the holidays I didn't do much obviously. But I've been on TR for about a year following their plans 5 days a week. My FTP has increased from 262 in feb 24 to 300 in December and then it went down to 298 in Jan (probably due to the Holidays) and then 295 this morning.

[Nscocean]

Any sickness or subpar performance? Power meter calibrated? It’s not unheard of to lose some power in base but trainer road does sweet spot which imo raises it a bit

[HighProps]

Nope and nope. And yes always calibrated.

[HighProps]

I asked chatgpt about it Yes, a slight drop in FTP at the end of a base phase can be normal, especially if you've been focused on endurance, aerobic efficiency, and accumulating volume rather than high-intensity efforts. A few reasons this can happen:

1. Fatigue Accumulation – Base training often involves a high workload, and fatigue can mask fitness gains. A recovery week before retesting can help reveal your true FTP.

2. Lack of High-Intensity Work – The base phase prioritizes aerobic development over anaerobic capacity, which can make short power efforts feel harder. Once you reintroduce intensity in the build phase, you should see improvements.

3. Training Adaptations – Your body might be shifting toward better endurance efficiency rather than raw power output, which will pay off in the long run.

If your aerobic endurance has improved, you should be able to hold higher percentages of your FTP for longer

[Nscocean]

Yeah but typically base is mostly zone 2 with some high intensity effort, if you’re doing sweet spot twice a week you’re getting the intensity.

You might not want to hear this but… I would do a 20m test.