Wahoo kickr user here: just did my second training (started easy) but I had trouble doing the 90Watts during the relaxing phase of the training, the resistance was very light and my cadence was about 80 - 90. I had trouble doing 360 with the pedals and keeping a good troke.
I would expect to cycle at cadence 50, some more resistance and give the legs some rest?
At a certain point, I was doing 60km/h downhill… when I never went beyond 50 irl (I live in the Netherlands = flat as a pancake). In zwift i was on a on 6-7% downhill cycling very lightly?
Perhaps I am doing something wrong?