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 >>/69776/
I think HR trace is so wildly individual it's not worth it to try and game it in some way. For me, easy endurance (bottom of z2, 190-200w) is usually 105-115, then mid-z2 (220-240W) is somewhere around 120-135, and high Z2 / LT1 (260-280W) is 135-150. But it varies so much depending on my training load and how fresh I am (the fresher, the higher the HR) that it's quite meaningless unless I look at longer term trends. The easy z2 is from today, felt quite fresh after a rest day yesterday. The mid-z2 is from a couple weeks back, quite fresh then as well. And then the LT1 one is from a couple days back after a harder threshold ride the day before. Power/HR varied between 1.71 (today) and 1.99 (LT1).