Single endurance workout execution drops AI FTP prediction by 8W

Training
1

Hi,
I have been reading various post about the sensitivity of the AI FTP prediction.

Just sharing my experience which is a little puzzling.

TR until this morning was giving me an FTP prediction of 252W based on my current plan.

Next prediction is due in 12 days (7 planned workouts).

Today I had scheduled an easy endurance workout. 1h and 15min which was very easy as expected.

After I was done with the workout AI updated the expected FTP to be 244W. So a 8W drop after an absolutely normal endurance ride.

The only few things “out of the ordinary” I can think of:

-I disabled ERG because it was giving me trouble and used resistance mode. so my power maybe was more fluctuating than normal. But still never missed the target as interval average.

-I stopped 30 seconds for biological needs

-I did the workout in the morning which usually produces a slightly higher heart rate

Any clue why this happened?

Side note: in the previous days the predicted FTP was always ranging in the 250-255 range. Variability depending on me changing to slightly different workouts few times.

2

Click on the ride, hit edit and uncheck the TrainerRoad AI box (temporarily!)

At least that way you can establish whether it’s definitely this ride and only this ride that has caused the change in the prediction.

You may need to make another change (eg move an upcoming workout forward a day and back again) in order to prompt the recalculation.

1 Like
3

Thank you for this suggestion.

I have tried and I did not see any change.

Then I did the same for the workout I did last Thursday (threshold over/unders) and the estimate went back to 251W.

So i guess that is the guilty workout. Not sure why the FTP prediction was update only after the last workout from this morning.

That being said, it was a workout I completed without failing and reported as HARD, which was the expected outcome from AI.

I wonder why it costed 8W to the FTP prediction…