A couple of bones to pick w. estimating TSS on outdoor rides without power



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…


+1 I like the Training Peaks heart rate TSS. I know HR is sort of old school, but given that many great champion trained with HR for a couple decades before power, surely it’s a reasonable alternative when power data isn’t available, and I’d say more accurate than PE.


I just get the value from Stravistix and enter it into the Custom RPE field in TR, it takes all of 2 seconds to do… :+1:t3:


Again, another +1 for giving us a hrTSS option. I know you guys don’t rate it, all of us that listen to the podcast know that, but as I’ve said before, I just use the RPE options to get nearest to the hrTSS that Training Peaks gives me anyway!


Which value do you take? The “stress score” from the fitness trend graph?


HR TSS way over estimates for me. I did a 6 hr MTB race where training peaks gave me a TSS of over 600 from HR. Even if my threshold HR should be 5-10bpm higher on MTB vs trainer, my TSS would still be over 500 which isn’t right.

I like the TR approach, which takes ride length into account also. So if I do a 3 HR race, and indicate race, TR estimates what my IF was and uses that to calculate TSS. The alternative of course would be for me to enter my IF myself, but I figure TR has a big enough database where they will come up with a better estimate than me.

If I get to the point where I want a more accurate measure of outside TSS, I’ll get power meters for my bikes, but for now I’m OK using the TR approach.


Automated HR TSS suggestion would be sweet. Or at least an indication of how to translate from HR manually… how many % of HRmax equals “hard”? I have no clue…


I think that whatever system can be created to automate TSS estimation has to include both heartrate and a power estimate.
RPE is just as bogus as HR alone and for exactly the same reason; suppose you have a regular loop - one you’ve ridden a hundred times. If you ride it feeling very fresh, your heartrate stays a little lower, your RPE stays a little lower; both indicators that would add up to a relatively lower TSS. Now suppose you ride the same loop at the end of a nasty week of training and it’s your second ride of the day; high heartrate, high RPE, high TSS. Except that the amount of work required to get around that loop IS EXACTLY THE SAME. If you’re knackered and you can only manage 150 watts and it takes you 2 hours to get it done vs. feeling fresh and you can put out 300 watts and it takes an hour - same TSS…