I have only recently started cycling and am using Rouvy with a Derito X smart trainer. What I am confused about is : If I do the approx 7 mile rides round London, Paris or other relatively flat rides I average about 13-14 mph and about 83-87 watts. The max power registered is always in the 100s - up over 200 at times. However. if I do a 'Workout'r and set the paoer bit to 90 watts I find myself almost falling off the bike after about 15 minutes. The full ride is 60 minutes . I have reached 20 minutes once but generally surrender after 15 minutes. Why the difference between the 'Workout' ribe and the 'General' ride. Allen

I'll take the 83w. 90w minus 83w is 7w. 7w is nearly 8% of 90w, if we take 90w at 20min to be your max.

Therefore, it's entirely possible you could do an hour ride at 83w instead of the 15min at 90w.

92% of what you can do for 20-ish minutes is what many folks can do for an hour. Yes, that 7w could make that difference in time duration you can do something.

In the meantime, take 92% of your 90w figure and put it into the workout settings "ftp" since that's the best you got for roughly 20min. Try again, and see how workouts go.

Welcome to BikeForums

Humans have a Lactic Threshold (LT threshold).
At a power level / Heart Rate below this threshold, the heart and lungs provide the oxygen required to power the muscles.
You will find you have good endurance below this LT Threshold.

Once you go above your LT Threshold, the Heart and Lungs can no longer provide all the Oxygen required, then you burn glycogen in the muscles.
There is a limited supply of stored glycogen and you can run out quickly.

I personally found at 80W I had good endurance. But at 100W I could totally kill my legs in just 10mins.
FTP Ramp tests indicated I should be able to go for an hour at 140-150W.... No chance!
It worked like this for months of self training. In the end I hired a cycling coach.
Coach found the issue... my diabetic wonder drug was the cause.
It was suppressing all the glycogen storage in the muscles.

YMMV

Barry

BTW - not knowing further details, it's possible for your age and weight 80W is a respectable output.
In my case 56yrs & 200lb this was not the case.
There are FTP calculations, than given your personal info will provide you an estimate of expected output.

Welcome to BF.

How about a few words regarding your opinion of Rouvy. Please.
Understanding you said you are just starting with it. I would be, too.

This is really a training to power question. As you are new and have a lot of headroom to improve, I would suggest not getting so hung up on hitting a power target for hour-long efforts. Just enjoy riding, ride as much as you can, mix up the intensity so your body continues adapting, and take regular rest days. Consider joining races or group rides if those types of activities would motivate you.

Rouvy automatically estimates a value for your functional threshold power (FTP) as you ride more. This value is crucial to performing the right kind of training with power in the right zones and for the proper duration. But just starting out you will be getting fitter and the numbers won't be all that helpful.

Rouvy is fantastic and I found it much more enjoyable than Zwift. I don't race, just ride for the enjoyment and I appreciate the Rouvy apps showing you real world roads and scenery. I use the training side of Rouvy here and there, but typically just use the routes and on occasion will join a group ride.

What I find is that holding a constant and relentless power output is harder than averaging the same power while free-riding where you naturally get little micro-breaks every time you lift off the gas. I also agree with the other posters that going from an 83W average to 90W is quite a significant jump if close to your threshold.

The Direto X is a great trainer too, with very accurate power measurement.

Burnthesheep does a good job explaining the reason.

There is a core concept in training to power called Functional Threshold Power: this is notionally the average power you could sustain in an all-out hourlong effort. People often test their FTP by doing an all-out 20-minute effort at 5% above their expected FTP. You're finding that a 20-minute effort at 8% above your usual ride is really hard, which seems to tally. I think you'll find that if you stick with it and train regularly, you'll make rapid gains before you start to plateau.

You can do an endless amount of study on structured training and training to power.