I just switched from Fluid2 to Kickr Core, but months of experience with the Fluid trainer (using a powermeter) on TR:
“It depends”. For small changes in power (i.e. ramp test steps), I preferred changing cadence until I got up to about 105rpm or so. I’m pretty comfortable from 90-105rpm, so I’d use that range as much as possible. If I needed to go too far outside of 90-100rpm, I’d shift.
I’d prefer to spin faster in a smaller gear, but I did some work at cadences in the 80s as well, especially when called for. That’s how I prefer to ride - speed endurance > muscle endurance.
It depends on the goals of the workout. Some of the workouts want you to work in a climbing gear with lower cadence, others emphasize a higher spin. Sometimes, I’d just kind of have to ignore the recommendations to hit target power… always target power first, then worry about choosing cadence on the dumb trainer.
No. The difference between operating at 90% of FTP at 95rpm and 90% of FTP at 80rpm should only be a few bpm, certainly not going from endurance/tempo HR to VO2 HR.
Having now switched to erg mode (using powermatch), I like being able to set and hold cadence through intervals. Many times, I’m not even really looking at power… I haven’t had the same “learning curve” to adapt to erg that others have noted, in large part due to discussions I’ve read on this forum, now having done threshold, sweet spot and VO2 work. I just set the cadence I want and hold it. So far, I prefer erg even with some of its limitations (e.g. living with power that’s not exactly on target, adjusting workout intensity to make power come up) because I can focus on one thing and not get all jumbled worrying about cadence, gearing, shifting to the next power requirement, etc.