Trainer warmup and the 3 sets of 15’ of (30”on 1’ off) cadence > 90 rpm. Low set point z2 upper set point low z3. I will equate the workout to getting 3 cavities filled using laughing gas versus novocaine.
What I have found using the Tacx in ERG mode is that running the big ring and an 11 or 12t rear cog provides the best road feel. I try to keep the rear flywheel going fast. Also, right now my HR is very sensitive to cadence since the power is set by the trainer. Increasing the cadence during the low set point at times resulted in a higher HR than at a higher power setting during the “on” portion. And I know the power is correct.
Also, the trainer tends to impact my knees more. I get more under the knee cap pain on the trainer than on the road. I tried an experiment where I taped my left knee with KT tape when I started to get a little pain after the 2nd set. For the 3rd set, the pain went away. One data point so may be just coincidence.