I’ve noticed a few things about estimating TSS for rides without power data that I think could be handled better.
The first is an issue with the terminology used: When I want to have TR estimate TSS on these rides, I’m asked to ‘Choose Intensity’ and then see a list of 10 intensities to choose from (Recovery, Easy, Smooth, Moderate, Tempo, Uncomfortable, Hard, Very Hard, Race, and All Out.) IMHO, this should be similar to the way the TR workouts are categorized so that, once you have some experience, you would have a pretty good idea on comparing the feeling of the TR workouts and the outdoor rides, but they’re not - if you use the filters for the TR workouts, you choose from 7 ‘Zones’ - (Endurance, Tempo, Sweet Spot, Threshold, VO2 Max, Anaerobic, or Sprint.) Additionally, in the TR workouts, you can choose from a list of different ‘Intensities’ ( - note, same term with a different meaning) (Recovery, Moderate, Hard, Intense, Insane.)
It appears to me that the terms aren’t being used consistently and that there is some overlap in terminology that may or may not mean the same thing. I believe causes some of the confusion and frustration with this estimation.
But that’s not all; I think that most of this can and should be automated; there has been man mentions on this forum of TrainingPeaks and their method to estimate TSS based on heartrate. Additionally, Stravistix has the ability to estimate power based on GPS coordinates (forward speed, vertical speed, whether you’re on a road bike or MTB, etc.) as well as your weight, your bike’s weight, etc.
I really think that TR could (and should) come up with a system that automatically performs the estimation in a fashion similar to what these other systems do - between all of the data available, I don’t see that it makes sense for me to be choosing whether my Saturday group MTB ride was Smooth or Moderate or Tempo…