Specifically take a look under “power testing”. In short, to use the 8020 structured workouts the recommendation is to do a 20 or 30 minute “all out” run test, and apply the average power for the run as your Lactate Threshold Power, rather than use CP.
Okay thanks that’s interesting. I’m curious how CP will compare to FTP but I was planning on doing an LTHR test tomorrow morning anyway so I’ll look at where Power is while in my LTHR zone and get an idea.
I share your curiosity! A week ago my CP was almost identical to my Threshold power. However, given that CP changes frequently (goes up and down), I am guessing that it will make entries into Training Peaks and updating 8020 zones very frequent. I have found that sticking with a consistent Threshold Power for a period of time and training on those zones helps me build fitness. I re-test the zones every 3 weeks or so, depending on the periodisation in my training plan.
Unfortunately my experiment with the Garmin auto-detect of doing a Lactate Threshold HR test failed to detect LTHR, not sure what I did wrong. Will have to wait a bit and try one of the other tests. Not relishing the idea of the 20min all-out test so maybe I’ll try the Talk Test instead.
FWIW where I *think* my LTHR is (about 164-166bpm), my pace was also about where I think it is (Half marathon pace), but my power watts at 289w were well under Stryd’s CP (autodetected at 301 currently). I recall reading somewhere on here that CP is more inline with a 30min max whereas rFTP is for a longer duration (1 hour), so in that case the number make sense.