The Calculators and Algorithms are Wrong
I hope you update your training zones regularly (8-12 weeks with regular training). But how you determine your zones matter too.
Recently, I had an athlete that was able to do a Lactate Test (LT), followed by an FTP test 2 weeks later. If you plugged in his FTP number (298W) into the calculators, it would say his top of Z2 power (76% of FTP) is 226W, while his LT results had top of Z2 at 200W. As you know, 25W can be a big difference in effort.
What is worse, the calculators said 130bpm would be the top of his HR Z2, where the Lactate Test had it at 101bpm!!! You can imagine how much harder you are working when HR is 30bpm higher on the bike.
If he had been working out at the calculated Z2, his easy days would be entirely too hard, leaving him unrecovered for his hard days. And likely detraining his FTP/Threshold power most days - just the opposite of what we want to do.
While each athlete is unique, I've seen this play out for nearly every Lactate Test vs. Calculated comparison I have ever done.
If you aren't updating your training zones regularly, start there. But if you want to take your training to the next level, set them with your biomarkers rather than some generic calculation. Book a test Today.