A new study challenges the hype around Zone 2 training, but Trevor and Chris explain why the real answer is more nuanced: intensity matters, Zone 2 still has value, and coaches and researchers need to work together to understand both.
Video Transcript
[00:00:00] Chris Case: Hey everyone. Welcome to Fast Talk YouTube edition. I’m Chris Case, Trevor Connor is sitting beside me here. We just exited the podcast studio. We wanted to give you a recap of what we at length in that studio. Today we’re talking about. A study and a, and a complimentary you will, on zone two.
Trevor, you were so giddy in the podcast studio that your shirt came unbuttoned and you were, you were overheating a little bit. You’ve buttoned up now. Um, this particular study, much ado about zone two is the brief title of it. It has been everywhere. Zone two is mentioned in so many um, not just in training science, but podcasts about and general health.
Tell us a little bit more about why this study makes a good point and then maybe gets a little off
[00:00:57] Trevor Connor: Yeah. It’s a study that’s been getting a lot of traction. particularly on social media because it is a study that is challenging, what’s really popular right now. Uh, and so you’re getting people on both camps really getting into this conversation, which makes it important. was really excited to read it and, and hear what it has to say. And it’s primary message is that we’ve gone overboard with you are seeing a lot of influencers, a lot of people saying, for our health, for our fitness, we should be doing all zone two training. Forget and zone two.
For anybody who’s hearing this for the first time, it’s lower intensity. It’s that. if you were a runner, you know, be kind of that fast walking pace, slow jog killing yourself. And I think. It’s main argument that unfit or just not elite we have gone too far, um, with zone two and that intensity is important.
And then there’s a lot of evidence showing that essential for both improving our health and actually for improving uh, aerobic fitness. And I think they make a good point there.
[00:02:24] Chris Case: Where do they go wrong,
[00:02:29] Trevor Connor: I think they take that argument and then take it to such an extreme on the other side. That they start making the same mistake that they’re arguing
[00:02:44] Chris Case: Mm.
[00:02:45] Trevor Connor: Um, they’re making the point that there’s this belief that zone two is great for us, but there just isn’t a, a ton of science to back they do very legitimately make the point. There’s a lot of evidence intensity but there is a giant difference between saying there is no research on And saying the evidence there is no research, you don’t That’s all you can say. And as you go through the paper, they go from something that I really agreed with going to that other extreme of saying, you know what? We really see all the adaptations and high intensity and the evidence is against, and they literally state this, that the, the bulk of the evidence is against any benefits of zone two training.
And start to make the argument that the gains are in high intensity, why would you bother doing zone And I think they’re making the same mistake that they’re arguing against just on the other Um, and even in their conclusions, they start by making that statement the bulk of the evidence is against any benefits to zone two.
And then actually, I, I don’t know if, if they’re aware of this counter, there are an argument where they start saying, yeah, but there’s no research on These studies haven’t been done on on zone two, so all they can say is we don’t have the evidence for zone but we also don’t have the evidence
[00:04:20] Chris Case: I think one of the other issues with the article is that. Uh, while they start out. And in the title of the article, it talks about the general They drift a little bit within the article and start talking about zone two in various ways, which don’t necessarily agree with what define zone two, if you are in more of a exercise physiology context. And that leads issues. The conclusions they draw from maybe not uh, beneficial as you otherwise would be.
Is that correct
[00:05:05] Trevor Connor: Yeah. my old advisor used to like to say the devil’s in this review you really have to look at the details and when you get there, there are some major And with zone two, you know, again, they’re talking about general population, but as you get into the study, they’re really just talking about zone two in general. And, and don’t differentiate that much between general population, but they start at the beginning and have a correct definition of zone two, which is just below, uh, LT one. is fairly low But then they get very inconsistent about their definition of zone two, I had to kind of go through it twice to find how, what, what sort of intensity they’re defining as zone And I don’t think anybody would agree with, with where they put it.
So at one point, at the very end, and it’s, it’s easy to miss, they define zone two as as less than 45% of VO two And I, if I went out for a walk, I think I’d be over of VO two max.
[00:06:11] Chris Case: the typical, what’s the typical in, in the literature?
what is more
[00:06:15] Trevor Connor: there’s huge individual variation.
You’re gonna have a lot of people define it very differently. But I’m gonna say if you wanted somewhere in a broad consensus, when you’re talking about an unfit population, zone two is somewhere around 60, 65%. When you’re talking about elite, it can be as high as So we’re talking much higher.
And there, this is important because many times through the review, when they are making the they talk about studies where people were exercising at 60% of VO two and they say that’s above I would actually say that’s either below zone two or at the low end. And then more importantly, they cite some other studies when they’re talking about high intensity exercise.
They cite some other studies where people are exercising at 65, 70, 70 5% of T seeing benefits, and they’re citing those as examples of why high intensity exercise is better. And I look at that and go, no, that’s So, and you can have some debate on that, but I think when you are defining zone two as less than 45%, you’re not gonna get any physiologist back you on that?
Just as importantly, you have to look duration. How long is the Um, physiologists resolved this a long time ago. That benefits of zone two takes time. Um, particularly, particularly when you’re talking about the sports population, like you have to be going out for a four or five hour ride or a two three hour run.
Um, and a lot of this research that they’re citing that shows no benefit to zone two. Several of ’em, literally, they and doing 30 minutes below 60%, which is a recovery I saw almost nothing that was over 90 to me, again, that is a mistake make a
[00:08:26] Chris Case: It seems like particular article has some significant flaws in terms of the methodology here, but some conclusions we can draw that are helpful
[00:08:40] Trevor Connor: Yeah. I think where they start is a really good message, which is we have to be careful about just accepting dogma and going with it, and we have to be really careful about taking anything to agree. If there are people out there that are saying, zone two is miraculous, don’t do zone two all the time, and you’re gonna have huge gains in your fitness. You’re gonna have the best health. I think they’re misleading you, and I’m glad this paper came out to challenge ’em and say, look, you’ve gone too Um, and certainly A CSM, their recommendations for general population, stay healthy and has a lot of And I don’t disagree with that at all. We need intensity. There’s proven benefits Um, but I think it, it is a balance And you can’t go the other way as well. And this is a, a mistake that we saw 15, 20 years ago in the science.
Where again, devil is in the details. Most of our research is on high intensity very hard to study zone two training, particularly when you’re getting into longer workouts. So there has been a bias in the lab to studying high intensity. So yes, absolutely there is a ton of research showing the benefits of high intensity.
There’s very little research showing pros or cons of zone two
[00:10:09] Chris Case: Mm-hmm.
[00:10:10] Trevor Connor: All that tells you is yes, we know there’s benefits to high intensity. We don’t know about zone but from experience, we are seeing people get a lot of gains from until that research is done, experience shows us it’s probably something that’s worth doing, but we should be doing
[00:10:29] Chris Case: And that speaks to an episode that you did recently about the dialogue between coaches and researchers sometimes doesn’t. Uh, it’s not a fruitful conversation because, uh, researchers might dismiss versa, but the two of them benefit each other.
Is that, is that, do I have that right?
[00:10:55] Trevor Connor: We’re gonna get a lot further if coaches and researchers are working together. And certainly 20 years ago you really saw ’em in different camps. And I can tell you reading the you saw the complete lack of experience of some doing tests on athletes information about most effective training where you just look at and nobody would ever do useless research, even though you found some because you just fundamentally don’t so there needs to be that conversation between coach and coaches also need to respect the I think any coach who just goes, I’m doing this all by experience.
I don’t care what the science I think they’re making just as big a But, and sorry. again, I support what they are trying to do with I did see an interview with the lead author. Where when experience was brought up, her response was, show me the research. was kind of dismissive and going, basically saying if there isn’t research, it isn’t real. So there, why would you do zone two? We don’t have research And when you are talking with a coach who has worked with Olympic athletes who has worked with Tour de France cyclists and seen huge value in zone two, and you’re dismissing them ’cause you’re saying, show me the research, which.
The research hasn’t been done. That’s a flaw in the research, not a flaw in the coach. That’s where I, I get on board with the coach saying, you know what? You’re not listening and I don’t know how, how many more conversations I want to have with So I think coaches need to be humble and say, let’s listen to the researchers, despite my But researchers need to be humble, and this is where I’m gonna quote Dr. is a lot more. don’t know about physiology than we do know about physiology, and researchers have to, to accept the fact that coaches have experience that hasn’t been improved they have to trust
[00:12:59] Chris Case: Hmm. Well.That’s just really the tip of the iceberg of what we talked about in the podcast, which we dove into much more of the biochemistry, a much deeper these topics. another paper, which ironically was much more nuanced, so check that out on our podcast channel.
