Good day everyone. I having issues with my trainer power compared to outdoor power. Here is a description of the issue:
I have a tacx flux 2 trainer. multiple ftp tests put my ftp on the indoor trainer at ±200w. On my mtb which I only use outdoor, my last ftp test put my ftp at 265w. I train every week both inside and outside. I currently use training peaks to schedule my training. on training peaks, i’ve set my ftp to the outside value (265w) and build my workouts using percentage of ftp rather than a fixed power number. On zwift (app I ccurrently use for indoor training) i’ve set my ftp to the 200w value. The percentages automatically set my power to the correct values for indoor training. when I sync my indoor workout back to training peaks after I completed it, I just manually change the TSS on training peaks to what zwift showed I have done. This will keep my CTL, ATL and TSB correct and accurate. Time in zones however aren’t accurate. Now I was wondering, is there a way to manually calibrate my trainer to read roughly the same power as on my outdoor rides? even though it will mean I artificially inflate the power numbers on the trainer, at least my power numbers will be similar and I can use the same ftp on both. I mean, for example if I do a set of tempo intervals outdoors, it will be at around 225-230w but indoors it will be at 160-170w. The power differs but the adaptations should be the same, so if I can get the trainer to read higher, match the power on the trainer to what I do outdoor and use the same ftp value, in theory I should be able to use training peaks’ time in zone feature and have it more accurately? I can also then use trainer road for the ai machine learning to build programs for me but only if I can change my trainer’s output readings. Otherwise the data on trainer road will be so different from outdoor rides to indoor rides that the ai features will be useless. Or is there a way to use two separate ftp’s on TrainerRoad for indoor work and outdoor work?
There are differences is my two setups which could be the reason for the different power readings.
My indoor setup: Road bike that is a size too big for me. Round chainrings and trainer measures power after all the drivetrain losses. I don’t have a power meter on the road bike. I only use my road bike on the trainer since I got the trainer.
My outdoor setup: MTB that is more my size. Oval chainring. Spider based power meter that measures before all drivetrain losses. The power meter is a Xcadey.
Note: I have optimized my cooling for indoor training, I focus a lot on hydration and fueling both for indoor and outdoor work. Heart rate during indoor and outdoor work suggests the effort level is very similar even though the power is so much lower.
Any suggestions?
Thanks