Do you want fatigue detection turned off? Adaptive training wasn’t any less opaque and was driven for months by the same workout picker that is currently being used.
Didn’t feel like starting a new thread on the same topic, so wanted to piggyback here and see if support or others can help me out.
I really seem to be struggling with my threshold workouts and TTE. This didn’t seem to be a problem during the initial beta period and felt like that was the most productive period of TR I had been on. When the new aiFTP prediction came out I went from 265 to 289 and feel like threshold has been a constant struggle since then. FTP did calibrate back down to 281 and have been working up since then. VO2 are hard but seem reasonable. SS seems similar, but threshold is always a struggle. I am just starting my 8 week specialty phase for a race at the end of May.
Link to my calender:
Here is a screenshot of today’s workout:
Made it to 51:20 before I had to backpedal. First hard start workout. First set felt great/easy, second was reasonable. Heart rate didn’t really recover a ton before third set. Could feel my legs being heavy with lactate during the third set after the Hard 30 seconds, but could feel it clearing as I went minute by minute. Made it about 5 before legs started to give.
Two weeks ago:
Made it to about 55:30 before similar issues where I feel like I just cant turn the pedals with power.
3 Weeks Ago:
Same issues start around 55:00 into the workout.
5 weeks ago:
No issues, but this is the first non-hard start or over-under workout I have had. I feel like I am decent at putting out steady power.
Any help or guidance would be appreciated. Don’t know if I am just struggling with processing the lactate from the overs, not actually being “under” and an FTP issue. Reaching my TTE for the power I have or what.
Cooling could be an issue as the room I am in tends to be warm and room temp will rise usually 3 degrees F, some humid mornings its closer to 5 degrees F in change.
Maybe I need to do my endurance rides at a lower percentage of FTP/change the approach? I’m kind of at a loss for why threshold always is a struggle. I know I am getting faster, but get kind of demoralized not being able to complete the workout as prescribed and then the FTP goes down.
I did have 2 rough weeks where I was basically off in build from a snowstorm and work travel, but feel like that isn’t the driving issue.
Appreciate any guidance or help.
How long do you think you could hold 285w for if reasonably fresh?
If your ftp work is feeling unreasonably hard I would tend to lean towards having an inflated ftp.
I can’t help, but can commiserate. The end of TH workouts are always my demon. I’m currently working with a much lowered FTP from what the AI wants me to use in an attempt to focus on extending TiZ for my SS and TH workouts.
Is there a reason you are only rating your failed workouts as very hard?
To me it seems that you have been pushed a bit too far with regards to FTP, but since you keep telling the AI that everything is fine it will just keep pushing you. Which then gives you the result you see now, a bunch of workouts that you struggle to complete.
I’d be rating those Maximum Effort, reason Intensity.
Had one of these at the start of this years training. Threshold and O/U was my nemesis, after rating the ride Max effort, it then led me into some Very Hards and now most are Hard, they now feel productive and manageable sessions.
What riding did you do the two days before? How was your off-bike nutrition on those two days and day of? How was your on-bike fuelling on those two days and day of?
As you didn’t mention nutrition, it’s either perfect or bad. 
This. If you have to back pedal or pause, rate the effort All Out not very hard. The system will adjust prettt quickly. I have found that if I err on the side of a harder rating (ie choosing between hard/very hard, I’ll go with very hard) if I’m undecided keeps me more on track for better workouts. This will impact your AiFTP Prediction but I don’t focus or care about that. Trying to look at the long term goals, which at 59 is becoming more of a hold my FTP over time versus increase it! 28 day detections are about setting the right workouts. Sustainable gains are made over months (and years).
If you had to bail out then the workout was by definition a Max Effort. There is no sense in marking it anything else unless you wish to guarantee a miserable experience on your next hard workout.
I dare say TR could perhaps program the system so that when a workout gets cut short it automatically gets rated Max Effort and you have to manually override it and provide another explanation for the failure (mechanical, cramps, or whatever).
Yeah, I guess I should go back and revise it. I think I’ve had a hard time marking it max effort as the overall workload hasn’t felt that way. I’m not struggling to get through every interval and some feel easier than threshold, it just feels like a wall comes on in that last set and I can still perform work, just not at the level prescribed.
Probably need to take the ego hit and accept the reduced FTP that will come with the max efforts. Likely will lead to more productive training though
How is your fueling before and during workouts? Even threshold shouldn’t go from almost too easy to impossible during a 75 minute workout.
I’m certain I read somewhere here that you’re meant to rate the workout based on how you feel in the final set of hard work.
Had 30/20s two days before, rated hard felt hard.
Day before was a 30 minute high Z2
Nutrition was fine. 60g carbs day one, just water for Z2. 90g for the threshold workout. Had a decent mix of carbs and protein both days. May have been lighter on hydration than optimal, had a lot of coffee Monday and Tuesday.
Working out first thing so no fueling before aside from a shot of espresso. Start drinking appropriate carb mix as soon as I get on the bike. Follow up after ride with an adequate breakfast and hydration.
I’m not going to bed starving so I think I should be able to complete the work. It’s not a bonk, just feels overwhelming to spin the pedals. I may try my next threshold workout in TR instead of Zwift as the ERG modes feel different and think that may be playing into this a bit.
Was also my first set of hard starts I’ve done with TR so don’t know if that is just an adjustment for me or what.
I’m not getting fail prompts on these. It will reduce the completed work level from a 4.1 to a 3.7 or whatever.
Awesome! Thank you 
I would look at Fatigue Detection as an added layer to prevent long term fatigue. It recommends to lower intensity or take a rest day to recommended workouts depending on what you are completing so you can keep your training on track. You could well complete the workout prescribed, but just like a credit card, you have to pay back the loan eventually. Fatigue Detection does this by small increments, most often you don’t know you’re fatigued until you get there, so the idea here is to pay that loan in small bits so you don’t have to all at once.
That said, lets dive into your training
It looks like your plan started Start Date: October 2, 2025, but you technically only really started training in December, with not that much consistency, then got sick late January for about 3 weeks. Up till then, I would not consider this consistent training, so backtracking, this creates about 6 months of little to no training data for the Fatigue Detection feature to really assess what type of training load you can consistently maintain:
Mid February is when you started training more and upping up your volume, but still plan adhesion was still a bit all over. We can also see that up till today, you’ve been rating your interval workouts as Hard, Very Hard, and even Intensity. I feel like maybe coming off your sickness and all of a sudden upping up your volume like this definitely triggered a lot of Yellow/Red Days + the post workout surveys confirmed that it was probably best to build volume slowly over time.
You also added weekly 4-5 hour rides to your plan, so these are definitely also causing a snowball effect with Red>>Yellow Days. Here is a great example:
However, I see Fatigue Detection quickly adapting to the volume it thinks you can handle, even without much consistency on training days. As you give it more data, the better it will respond. Here is a great example of how it has adjusted where that weekend long ride did not trigger a Red Day the following day:
Moving forward, your Masters plan is composed of 2 interval days and 2 endurance days, however, we have to be considerate of your 5 hour weekend effort + Strength Training. It seems like weekly, you’ve only been able to consistently hit 3 workouts per week, so I would recommend changing your plan to be 3 workouts a week: 2 interval days + 1 endurance workout which you can swap to be your 5 hour Group/Solo Ride. Quality over quantity is what we want
I propose this schedule:
MON- Off
TUES- Strength Training
WED- Interval Training
THURS- Strength
FRI- Interval Training
SAT- Off
SUN- Group Ride
Note: if you can couple strength training after your interval workouts this can also allow to have additional full recovery days!
I also wanted to mention to look at Fatigue Detection as a tool to better manage training vs. recovery. For example, if you have an interval day and the day after is being flagged as a yellow day, then this is a sign that you may want to schedule the following day as an endurance or off day to properly recover for the next interval session.
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Hey @joxer72
Of course! At the end of the day you know yourself best.
Like I mentioned to @Overratedcarbon, Fatigue Detection is aimed at preventing long term fatigue and it tells you when you might be overdoing it with Red and Yellow days on your Calendar.
It doesn’t tell you if you can do today’s workout or not, in fact, you could complete a workout perfectly, but if you push past the boundary of productive fatigue, it will recommend adjustments to keep your training high-quality and consistent.
Think of it like spending on your credit card when you’re close to your limit. Every workout has a cost. Yellow and Red days are warning signs you are spending too much. If you are spending too much, you have to adjust your spending habits to get back on track.
Now I want to clarify that Fatigue Detection is the same as to when we had Adaptive Training, this feature has stayed the same. What is new is the AI Training window, which has replaced Adaptive Training.
As far as going back to Adaptive Training, this is not possible as the entire system has been revamped with the AI Training window; which is short is a window where you can see all workouts in the AI Window being adjusting live for the entire 4 weeks ahead based on what you are completing or changing within the window. This allows you to see how your training or changes to the calendar affect your future training, not just workouts within the zone completed. That said, if you would like to point me to specific examples of things you’re having confusion on, I am happy to help!
Note: these live changes to workouts are updated only within the AI Window as you progress through the plan. Adaptive Training did something similar, as the adjustments only happened within the current training phase you were on, not based on the long term plan. The way we build plans has not changed either, so the structure is the same, Base>>Build>>Specialty. However, how we recommend workouts has, which is based on your power data instead of Progression Levels, so you get better workout recommendations for your current fitness with lower failure rates or workouts that may be too easy. You no longer have to way to complete workouts within each training zone for the system to “catch up.”
More info here:
We also have great podcasts with out CEO Nate going into details:
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I will circle back to this one Monday !
How many fans do you have?
What fuel and water are you taking during your workouts?