Working Out Cadence/Wattage issue


(Jack) #1

Hello everyone,

In the past couple days I’ve set up my first trainer (Tacx Vortex) and have dived straight into the ftp test and working out, I’ve started on the train me up workout schedule as I’m doing cycling for badminton fitness, The first workout had me going at 90 rpm and 130 Watts which worked fine and was great but then it had a 60 rpm with the same output. Here’s the issue

I was on my highest gear going at 60 rpm fine but I couldnt reach the watt goal. Is is there an issue with my wattage calculation or is erg mode not working, half way through the exercise I changed it to incline and decided to just use my gears for the workout and I was reaching wattage goals within cadence goals

TLDR: erg mode not applying enough resistance to reach both wattage and cadence goals in a workout

Thanks, Jack


(Robert) #2

About the same problem here.
Tacx Genius (aligned and calibrated) for control
Rotor Inpower (calibrated) for wattage input.
Garmin Express not running.
Workout from trainingpeaks, ERG-mode on, but an average a deviation of 8% from set value. Set 190W ERG steering on 170W. Only a lower cadence decreases the deviation.
Sometimes the workout asks me to put in more power, but if i do the ERG wil ease the control to go back to the off-set.

Very frustrating, because my training is too light now. Help!


(Gerrie Delport TeamODZ) #3

I think this is your problem, you use two different sources, and you create a pretty big loop for the data to control your Power.

ERG is something programmed ito the trainer so the trainer does all the math, so if you use the trainer for power and ERG then all should be good. But you introduce another source, so now the trainer has to wait for the power meter to send the data and then adjust and this all take time.


(Robert) #4

OK, so all Zwifters with a powermeter have this issue?


(Gerrie Delport TeamODZ) #5

I would assume that this would be common for people that use a Power meter and a smart trainer in ERG mode. for some trainers it will be less significant and for others more. Depending on the accuracy of the two units.

I would suggest doing workouts with ERG off, and adjusting the resistance with your gears and the incline buttons in the companion app, you can also use the ± keys on your keyboard