Did the Rouvy FTP test this past weekend and I am confused about it.
Did an FTP test last year on a dumb trainer with Garmin Vector 2- got 280
Did Rouvy test and got 278- no big change which isn’t my question-
During the Rouvy test as it progressed my cadence kept dropping and I continued to shift gears
and got down to the point I was at 40 cadence- This did not happen when I did the test
on the dumb trainer- Just confused about what the heck is going on?
This low cadence makes me question the validity of the test-although it came in
about the same. (Lets not dwell on no gain- 48 years old/off-season in WI right now- did it just to test)
Lets assume I have no idea what the Rouvy FTP test is…well, because I don’t.
Maybe this is a stupid question that would be answered by a definition of the rouvy FTP test. But, are you not in control of your own cadence? Why would you let your cadence drop? Why didn’t you downshift to a lower gear to keep your cadence up?
We’ll see what Dr. C says, but you did a test on a dumb trainer and then a smart trainer, correct?
Different set of conditions and protocols. I use Rouvy and when I do the ramp test I stop when my cadence drops more than 10% from my normal and I can’t pull it back up. 40 rpm sounds like you were well into a “smart trainer death spiral.”
FTP is one hour max power.
Optimal cadence for 1 hour is between 90 and 105 RPM. You can check on all HR attempts 
If testing over 20mn (and removing 5% to get FTP) optimal cadence is slightly higher.
My normal cadence is between 85-90
So as I did the FTP on the Rouvy program it had an estimated FTP from previous workouts
and did its Smart trainer “magic” with that number.
I continued to downshift gears trying to maintain my 20min power as prescribed.
290 watts is 290 watts but when the cadence drops that low
it would seem to me to destroy the validity of the test.
Just wondering if anyone else has run into this with a smart trainer and any ideas about
how to fix. Want to plan another test in a few weeks but should I move my bike
to the dumby and go from there or is there something I am doing “wrong?”
Thanks for any and all insight
IM-MOO 2019- fourth times the charm
I guess I don’t understand. A smart trainer will pull the same watts out of your leg regardless of the gear you are in. Shifting won’t change that. If it is set to hold 250 watts, that is what it will hold. The speed of the back wheel will have no effect
Doing a 20 minute FTP test on a smart trainer doesn’t seem viable to me. What do you set the power at? A guess at what you can do? If you guess wrong and can’t finish how do you calculate FTP? If you guess too low and blow through it do you have to do it again at a higher power? Those problems are why most people either take the trainer out of smart mode and use the bike’s power meter, or do a RAMP test. Rouvy has several RAMP tests that seem to do a pretty good job of “guesstimating” your FTP.
Thanks AutoJack
That is exactly what I was looking for in the sense of
what to use. The ramp tests are what I will check out.
New to the Smart trainer world and missed some info along the way
Much appreciated
t
Hmmm…I thought what you were describing was “erg mode” of a smart trainer. But, don’t smart trainers have a normal free-ride mode?
Optimal cadence for 1 hour is between 90 and 105 RPM. You can check on all HR attempts
What’s the crank torque from all the HR attempts? Is that the optimal crank torque?
my understanding of the rouvy ftp test is it uses erg mode during the 20 min portion rather than a resistance mode like Zwift/TR etc. https://support.rouvy.com/hc/en-us/articles/115004249965-What-is-FTP-
You don’t need to shift, you just need to bring your cadence back up, but it is a death spiral if you let your cadence drop because if you slow your cadence the trainer resistance increases to keep power the same. They want you to manual decrease the power output in the app if you can’t sustain it. I don’t recommend using ERG mode for an FTP test
If you’re doing a 20 minute test you shouldn’t be in ERG mode, not sure about Rouvy but last Zwift one I did it switched the trainer from ERG to resistance mode when the 20 minutes began.
The ramp test’s are ERG.
With any ERG workout the trick is to keep your cadence up, with a set power the only way to reduce the force is to increase your cadence.
Let’s say you’re riding along at 200W / 90rpm & the next interval (250W) starts, to achieve this the trainer will increase the resistance by 25%. At this point your cadence might start to drop, but if it does the resistance will have to increase to keep you at 250W.
At this point to reduce the resistance you could increase your cadence by 10% to 99rpm, initially this will mean that you’re putting out 275W, however the trainer will recognize that you’re over target and reduce the resistance to bring you back to 250W.
Best plan is to increase your cadence & get it set >10 seconds before the start of an interval then when it starts don’t let it drop 
Hmmm…I thought what you were describing was “erg mode” of a smart trainer. But, don’t smart trainers have a normal free-ride mode?
Oops. Incomplete thoughts and sentences.
Rouvy runs in resistance mode in VR and course mode, and ERG in training mode. That is not software switchable. All of the FTP tests that I’m aware of are in training mode, hence ERG. I assumed the OP was running one of the canned FTP tests in Rouvy and that was my entire mode of thought answering this thread.
I’ve only had one smart trainer, never even played with others, but my Magnus will go into manual resistance mode if I pull the plug out of the wall. It feels like a dumb trainer with a small flywheel. That also disconnects it from Rouvy. When I first got the smart trainer I had been using Rouvy since it was called Virtual Training. My first FTP test was a 20 minute run with the trainer unplugged. I had my Quarq connected to Rouvy so I could see my progress, just like I did before the Magnus. I didn’t really know any better until later when I made the OP’s mistake.
Hope that clears things up. BTW. I now do an FTP test using a RAMP test where power goes up 30 watts every 60 seconds. I calculate FTP using the last completed ramp power plus 30 times the number of seconds I held the last ramp divided by 60. That appears to be very close to a 20 minute run times .95 on a dumb trainer, and much easier to do.
I’m interested to ear from you about optimal crank torque, and how it impact optimal cadence, for FTP or for my HIM race pace.
Nailed it- the trainer went to erg mode and the Death Spiral began
My question then becomes will a Cycleops Hammer work well enough in free ride
mode to do an accurate FTP test? Will it provide the needed resistance to get an accurate FTP?
Otherwise the ramp test is my next best bet I am guessing using Rouvy
I’m interested to ear from you about optimal crank torque, and how it impact optimal cadence, for FTP or for my HIM race pace.
Yeah, right.
Basing optimal cadence on the cadence of HR attempts makes just as much sense as basing optimal crank torque on the crank torque of HR attempt. Basing the cadence of a HIM on the cadence of a HR attempt makes just as much sense as basing the power of a HIM on the power of a HR attempt.
My question then becomes will a Cycleops Hammer work well enough in free ride mode to do an accurate FTP test? Will it provide the needed resistance to get an accurate FTP?
I’m almost positive the Hammer and the Magnus use the same resistance unit. I know in Rouvy under trainers they are grouped as one selection.
My Magnus will provide about 400 watts of resistance unplugged. I never tried it plugged in with Rouvy shut down to see if powering the unit would make a difference, but it shouldn’t make it any weaker. I would say you have a pretty good chance that it will work.
FTP is one hour max power.
Optimal cadence for 1 hour is between 90 and 105 RPM. You can check on all HR attempts
If testing over 20mn (and removing 5% to get FTP) optimal cadence is slightly higher.
Optimal cadence for 1 hour depends on how fast/how much power the person is putting out.
Someone going 20 miles in an hour would probably be at a lower cadence than a person going 28 miles.
I’m interested to ear from you about optimal crank torque, and how it impact optimal cadence, for FTP or for my HIM race pace.
Yeah, right.
Basing optimal cadence on the cadence of HR attempts makes just as much sense as basing optimal crank torque on the crank torque of HR attempt. Basing the cadence of a HIM on the cadence of a HR attempt makes just as much sense as basing the power of a HIM on the power of a HR attempt.
???
Not sure what you are talking about.
My question then becomes will a Cycleops Hammer work well enough in free ride mode to do an accurate FTP test? Will it provide the needed resistance to get an accurate FTP?
I’m almost positive the Hammer and the Magnus use the same resistance unit. I know in Rouvy under trainers they are grouped as one selection.
My Magnus will provide about 400 watts of resistance unplugged. I never tried it plugged in with Rouvy shut down to see if powering the unit would make a difference, but it shouldn’t make it any weaker. I would say you have a pretty good chance that it will work.
I assume it’s progressive, like a dumb trainer? Hard to imagine its a flat 400 watts of resistance, regardless of wheel speed, without any electronic gymcrackery reducing the brake torque as wheel speed increases.
Rouvy runs in resistance mode in VR and course mode, and ERG in training mode. That is not software switchable. All of the FTP tests that I’m aware of are in training mode, hence ERG. I assumed the OP was running one of the canned FTP tests in Rouvy and that was my entire mode of thought answering this thread.
That must be a Rouvy specific thing. On The Sufferfest they specifically instruct you to make sure your trainer is in ‘slope’ mode (equivalent to VR) and not ERG mode, when doing their FTP or 4D power test. On Zwift, the FTP test is also done in slope mode. You ride as hard as you can sustain for the required duration and try to hold a steady output, without the trainer regulating the power level.