My weekly schedule gives me 3 chances to ride each week. I commute to work twice a week which takes 3-3.5 hours. I do threshold or sweet spot intervals for the first half of the ride usually, depending on the phase of the plan. And I do one 45-60min lunch ride with VO2 or anaerobic intervals. That’s my week. I can really only do intervals for the first half of the commute because the second half is on city bike paths. I’m trying to follow my plan in terms of the interval workouts, but I feel like I need to maximize each day with only 3 days per week so I’m consistently adding extra endurance miles and sometimes an extra interval or skipping rest, especially for sweet spot. I’ve only seen a decrease in my FTP since the launch of TrainerRoad AI. Right now it’s 270W and my threshold intervals feel like sweet spot. In an act of stubbornness and defiance, I did a 20min test after my threshold 5.1 workout this morning and did 305W. That would traditionally put my FTP at at least 290W. I’m conflicted because TrainerRoad’s FTP number is bumming me out, but I think I’m getting faster. So is TrainerRoad AI accounting for the extra work I’ve been doing and giving me easier intervals knowing that I’m consistently piling on extra and don’t need as intense of intervals during the structured portion of my workouts? Or is it just wrong and I could be doing harder intervals?
Are you following structured workouts? (E.g. TR outside)
In my experience the AI FTP is less accurate if you’re relying on unstructured rides. Although I’ve never had it be miles off.
Honestly it is probably the extra work confusing the model a bit. Those systems expect a certain structure, so when you start stacking extra endurance miles or sneaking in more intervals the data gets messy. I had the same thing happen when I kept adding bonus riding after workouts, the AI thought my threshold work was easier than it should be and nudged FTP down. Your 305W for 20 minutes tells a clearer story anyway. If threshold feels like sweet spot, your FTP is probably set too low and the algorithm just has not caught up yet.
Yes, following structured TR workouts before adding extra miles.
I should try separating my long ride into two structured workouts. The hard intervals and an endurance ride. Maybe it would interpret it differently.
You say you did a test: why not just manually update the FTP and see what happens? (Account > FTP is right at the top)
My guess is that the AI is making predictions based on where it thinks you are, but it’s out by 20W for some reason. It might come back into the right ballpark, but it might take a few iterations.
The other option is to force it to gove you a much harder workout than thr AI wants to for a little bit. I saw somewhere in the forum that if you’re being given threshold < 3 it thinks your FTP is too high.
From what I can see on the back end, your FTP prediction for today is actually a handful of watts higher than what we predicted on March 6th.
The 20 and 60 minute power estimates are pretty close as well..
I looked at that data for the day after your 20-minute test, and your 20 and 60-minute estimated power was pretty much spot on as well.
I think where your FTP falls between those two figures can be tricky to determine, especially for athletes who are completing workouts in the way you are.
Since you’re often doing the work that’s prescribed in your workouts, but not in a truly 1:1 fashion in comparison to the TR workout, it can be harder to make assumptions about FTP. We’re looking at the watts, and if there is a ton more time between intervals in your ride data than the workout (as in your February 21st workout), it’s not exactly comparing apples to apples (this is just one example).
Nailing Outside Workouts with precision can be really tough, and sometimes you need to modify the workout, as you’ve been doing, in order to get the work in, which I do think makes it a little harder to decipher, and when we do look at the data, it’s not likely as strong as if it were to match the profile of the workout perfectly.
I think this, alongside the irregularities in your training schedule, probably leaves us a bit more conservative with your FTP detections.
I will say that what we’re recommending for today is about halfway between what we recommended on Friday and what you manually entered on Sunday, so we’re not too far off. The cool thing about how TR works now is that regardless of what you have your FTP set to, we’ll still get you workouts that should be appropriate for you. A higher FTP will generally get you lower-level workouts, and vice versa.
Let me know if this helps and if you have any other questions. 
I would say the February 21 ride was an anomaly. I was riding with my wife and tried to find a TR workout after our ride that roughly matched the intervals I did ad hoc during the ride. In general I try to follow the structure in such a way that I do not extend recovery intervals. Recently I have been reducing or eliminating recovery intervals to fit a TR workout in less time than prescribed since my bike commute really only allows for 1:15 of intervals. Do you recommend my approach of splitting the structured interval workout portion of my commute into a separate workout from the endurance miles portion that is usually the second half of my commute?
As a separate question, does it matter to your system if you hit the lap button and get the workout completed alert on the garmin, then continue riding, or continue riding while still in the cool down interval without ever hitting lap to complete the workout?
I’d love it if you could address my follow up questions. Thanks.
If you don’t have enough time to fit in a specific workout, I’d recommend using Workout Alternates to find one that you do have time for.
If this is a common situation that you run into, you could always change your schedule to fit your needs, too.
In terms of riding after your workout is complete. Feel free to end the workout on your Garmin when it’s finished and then continue riding.