He defined it as 2mmol of lactate for those technically inclined. My understanding is that is going to be tempo to sweetspot for most. Probably the more well trained one is, the higher the intensity to achieve 2mmol.
(edit: was responding to Twowkg’s deleted post.)
I blame ISM for all this “zone 2” confusion plus he’s been vague and all over the map on what exactly his zone 2 was over the years. I mean, when he first started talking about it and calling it zone 2, everybody naturally assumed it was zone 2 based on the Coggan classic chart.
I first recall him saying it was point where you can still pass the talk test. To me that is edge of VT1/aerobic threshold.
Then on Peter Attia he said it was precisely 2mmol of lactate.
Anyway, there is nothing magical about his zone 2 and it was “invented” by others who probably got it somewhere else. I seem to recall Coggan called it TAN - tough as nails rides. Tim Cusick has used the same language probably crediting Coggan.
Haha I didn’t delete anything. I think the forum was cleaned up a bit.
Currently riding but in a Peter attia interview he said it was Fatmax iirc. So below lt1. But just barely so.
Yeah, he’s said so many things over the years. His 2mmol on Peter Attia seems to be the most precise. In the end it’s tempo to low sweet spot.
My understanding is that the way the pros use this ISM zone is while out on their 5 hour 250 watt coggan zone 1 endurance rides, they toss in some spicy tempo to sweet spot intervals.
Pros don’t do it Peter Attia style - a monotone, single intensity 2mmol session.
Why would someone clean up your post? It wasn’t controversial? I see that the other guy’s post that you responded to is gone. They are now all gone.
No clue 
. I just saw your response and then noticed nothing from the last day or so was left.
I am seeing a lot of runners doing the mixed zone training too. One of my friends who coaches a very elite cross country runner had them do a tempo, some fast sprints, more tempo, some hills and VO2 all in the same session. It would make the stick to the zone people crazy.
Kinda wacky to look at the workout but it works.
I think with the pro cyclists, at least, it’s just spicy endurance intervals on an endurance ride. Nothing one doesn’t come by naturally living in a hilly area.
Yesterday I shared Photo and link from YouTube and it was removed. so I will not share again.
However I want to share about Z2, now if you ask ChatGPT what is Dr.Inigo Z2 it will tell you that it is around LT1 (up to 2.2 mmol Lactate Level)
And if you let ChatGPT construct training for you with your lab data. It will help you understand Z2training a lot easier by real experience. 
I’m fairly certain that lactate levels vary from one athlete to another, similar to HR zones, so using that to determine “Z2” might not work across the board.
I think, generally speaking, he’s referring to fatmax, which, for most athletes, is somewhere between high Z2 (endurance) and low Z3 (tempo).
Everyone is allowed to share links, photos, videos, etc. as long as they follow the forum guidelines.
We do have some tools that automatically flag spam (and there has been a lot of it lately), so it’s possible that what you shared was flagged @Worawut.
We try to do our best to stay on top of things by flagging and removing spam, approving and rejecting flags, etc., but sometimes things might be misinterpreted or misjudged.
If anyone ever has any issues with this type of thing, please don’t hesitate to reach out! 
Maybe you need to check in on this spam tool? It seemed to delete all of Worawut’s posts yesterday including some replies.
I thought it was overaggressive moderation with a subtext I didn’t understand.
The spam tools doesn’t have control over anything on the forum. It just flags things for us to review.
I just did some digging and it looks like that post from @Worawut was flagged by another forum user and I approved it. I think that was my fault for not looking closer. Again, we review quite a few flags each ay.
My apologies! I’ll be more diligent moving forward. 
There are still quite a few missing posts from this thread. I don’t see the original post from Worawut or any of the responses to it?
When I deleted the post, it likely took direct responses with it. I was able to restore all of those posts. Take a look.
I see them now! Ty.
ChatGPT is a probabilistic language generator. It is not a reliable source of truth.
I mean it always tells me my training is revolutionary and amazing so it must be correct.
It is very good at reflecting bsck at you, whatever you ask.
My Hospital test from last year and this year.
There are 2 Fatmax points, Higher is Z1, a little lower one is Z2.
I was not improving as much as I expected. I think I was training too much or not optimal fueling. I just started training and learning from ChatGPT. Next year I will do the test again and I will see how it goes.
Absolutely. Same with me
