How to determine TSS when riding outside

I’m going to try to address this in the nicest way.

If you can swing it, get yourself a power meter for outside and to use with powermatch. Many trainers are known to not quite be as precise as they should be.

Once you start collecting data and learn how the different zones and tss levels feel, it becomes much easier to “estimate” your tss from rides where you may not have a pm. HRtss is nice, but nothing trumps feel and RPE. If I go for a ride on my mtb or cx bike I do not have a power meter and will only sometimes wear a hrm. I can usually estimate my TSS within 5-10 of the hrTSS value given by training peaks because I just have this experience built up.

Get the power meter. It’s literally the best tool you can use to start accumulating the knowledge you need to train your body in the proper way.

@kjtrailrunner thanks for the input. Great to hear from a fellow Snake devotee. I have 2 belt buckles also but the event always seems to beat me up no matter my fitness. I guess that’s part of what makes it so popular.

The calculator at SpinLoose seems to give a reasonable estimate.

Intervals.icu will estimate TSS from HR data. If you have previous rides with power and HR it uses a model specific to you, otherwise it uses a general model either based on “time in HR zones” or average HR. All your rides need to be on Strava.