[00:00:00] Speaker A: Welcome to the Heart Rate Variability Podcast. Each week we talk about heart rate variability and how it can be used to improve your overall health and wellness.
Please consider the information in this podcast for your informational use and not medical advice. Please see your medical provider to apply any of the strategies outlined in this episode. Heart Rate Variability Podcast is a production of Optimal LLC and Optimal HRV. Check us out at optimalhrv.com Please enjoy the show.
Welcome, friends, to the Heart Rate Variability Podcast. I am so excited for today's episode that there was a little bit of buzz at the APB conference about this young man who had done this study. And I remember Josh, like, Ina bringing you up to me and say, this is the guy. And I knew exactly what she was talking about because the world has kind of been waiting for this study, or at least my world has. So I'm so excited to talk to you today about your work and interest in heart rate variability. So my guest today is Josh Marchin, and really just excited to explore your study, your interest in this. But, Josh, just. Just for our audience, give us a little bit of introduction about yourself.
[00:01:20] Speaker B: Yeah, yeah. Thanks, Matt. Well, I'm Josh Marchant. I'm a clinical psychology doctoral student.
I'm at Brigham Young University in Utah. So I'm working with Dr. Patrick Steffen, who's an expert in a lot of this stuff.
[00:01:33] Speaker A: And friend is the show.
[00:01:36] Speaker B: Yes, yes. And, yeah, this is my first year in the program and really, really fascinated by heart rate variability research. I feel like there's a lot of avenues we can take with this kind of research for helping people's mental health as well as performance. You know, I'm more interested in the mental health side, but I think that there's just so much utility for this, and often it's an area that gets overlooked when we're treating people is the physiology. So I just think it's a really cool area of study.
[00:02:04] Speaker A: Awesome. And I'm kind of wondering, did you just kind of, as you're wondering, BYU, you run into. Dr. Stefan is like this. This is the coolest guy I've met. I want to. I want to follow whatever his research is. Like, how does a student get into nowadays heart rate variability?
What was sort of your path to this science?
[00:02:26] Speaker B: Yeah. Well, I have to give a lot of credit to Dr. Liz Conrad and Sheila Crowell at the University of Utah. I was working on their baby study, and we were looking at heart rate variability in mothers and in new infants and how, like, emotion dysregulation got passed from one Generation to the next and super fascinating research.
And then as. Yeah, Dr. Stefan, he's studying all this great stuff related to integrating psychophysiology and biofeedback into psychotherapy, which is just.
It perfectly fit in, I feel like with what I wanted to do in my prior knowledge and integrating into that, like with mental health work. So I think it was just a. It was a great match. And I love working with him. He's a great guy.
[00:03:11] Speaker A: Yeah, he's one of the great people in the field with a field full of a lot of them. He's. He's stuck out me for sure. So you're interested in this and then you come up with this study. And it's a study that I know Ayena was so excited because we throw out. There's a lot of breathing techniques out there. And I think a lot of people just assume that there's good research behind each and every one of these techniques. One of the ones you study. And I know I started nerding out the 4, 7, 8, like, oh, it helps you sleep or this, that the other. And I was almost ventilating at night trying to utilize this method.
But I would love to just what brought you to this study? And let's dive into your work a little bit.
[00:04:04] Speaker B: Yeah, for sure, for sure. And I have to give a lot of credit to Ina and Patrick. They came up with a lot of the initial conceptualization of this study. Study.
A lot of people in Ena's practice ask her about these techniques, find out if they actually work or not. And it's crazy. Like, you know, square breathing, box breathing. Some people call it tactical breathing. It's been mentioned in time magazine, the com, WebMD, like everywhere 478. Breathing is a little bit less popular, but a lot of people are familiar with that one too. And it's surprising the lack of evidence supporting these techniques. There's like maybe three or four studies with kind of inconclusive findings. And yeah, it's. Yeah, it's crazy how much people use these techniques and how little research there is about them. So we were like, let's put them to the test, see if they actually work.
[00:04:55] Speaker A: Yeah, I think like box breathing. For me, working in schools and even maybe in a book that I wrote with my wife, who's a second grade teacher, we talked about box breathing because, you know, it's just so. Especially in education, it's a really kind of cool visual that that young, like second graders can even follow.
And just assuming that there's a whole bunch of research behind this. So I, I'm interested, as you dove in to, to this, what was kind of some of your surprises that you, in the research that you were seeing?
[00:05:34] Speaker B: Yeah, well, I'll talk a little about kind of a study design first and. Yeah.
[00:05:38] Speaker A: Awesome.
[00:05:39] Speaker B: We had 84 students come in at BYU and we had them do a baseline measurement of physiology and of mood and blood pressure and all these different things.
And then we had them each do each of the techniques so we could look at how when one person was doing each of these four breathing techniques, how it affected their physiology. Because everyone's baseline is a little bit different.
[00:06:03] Speaker A: Yeah.
[00:06:04] Speaker B: We switched up the order people did these in. So it wasn't like everyone got square breathing first. People got them in different orders.
We had him do each of these techniques for 10 minutes each. So we compared square breathing, which is you breathe in for four seconds, hold for four, breathe out for four, hold for four to four, seven, eight breathing. You breathe in for four, you hold for seven and you breathe out for eight.
And then we compare those to six breaths per minute breathing, which is pretty simple. You just breathe in for five seconds, breathe out for five seconds, you know, six breast a minute. That actually has a ton of research behind it.
[00:06:41] Speaker A: Yeah.
[00:06:42] Speaker B: And then we also looked at the, the ratio. If you breathe in for four seconds and breathe out for six.
[00:06:47] Speaker A: Yeah.
[00:06:47] Speaker B: That change things up a little bit, a little longer breathing out. Um, so we had these four different techniques that they did.
And I think, well, maybe not this is what we hypothesize, but I think it'd be surprising for a lot of people, is that heart rate variability, which was our primary measure, increased a ton during six breaths per minute breathing.
But it really didn't change much during square and 4, 7, 8 breathing, which I think is just surprising for a lot of people, that the six breaths per minute breathing, which is a lot simpler, a lot easier to do, is doing a lot more for people physiologically like self regulation and stress wise than is square breathing or 478 breathing.
[00:07:34] Speaker A: Did you have any sort of insight, thinking deeply about this, let's start initially with square breathing of why we may not be seeing some of the benefits I would assume we would have seen with this well integrated breathing methodology.
[00:07:54] Speaker B: Yeah, well, that's a great question. I think it really comes down to the idea of like resonance frequency.
We can think when we're breathing around six breaths per minute. You're matching up your breathing rate and your changes in your heart rate and you're matching those to your changes in blood pressure and you just get this like kind of this perfect storm where your body is regulating itself so well. And for most people, that's around six breaths per minute.
With square breathing, you have these pauses in there where you're holding your breath. Same with 4, 7, 8 breathing.
And you just don't have time for your, your breathing and your changes in heart rate to match up so, so in sync as you would with six breaths per minute breathing. So I think that's part of the reason. I'm sure there's lots of other reasons physiologically, but I think that's the main reason is you're just not hitting that resonance with your body's internal signals. Things aren't syncing up as well.
[00:08:52] Speaker A: Yeah, that's what I think is really fascinating and in some ways logical when you say that like, you know, being so in residence frequency breathing and like having integrated into my, my mindfulness practice for ever since I pretty much met Ina, like I, I feel the power that, that it has. But you know, the, you know, when I start to think about like the square breathing, you're really not breathing, you know, anywhere kind of close to your heart rate in those pauses. What are we doing during those? I mean, are we. Is it parasympathetic? Is it sympathetic? Like there's, you know, it just, it just started as I was thinking about your study after I heard about it does kind of make sense that we're not seeing that, that same impact on heart rate variability.
[00:09:43] Speaker B: Yeah, for sure, for sure. And I think just like, just thinking how people feel when they're doing the techniques. It's often, I mean, the square breathing and the 4, 7, 8 breathing, some people really like them, but for a lot of people, it feels kind of unnatural. Like I'm stopping.
When people get into that six breaths per minute breathing and they're close to their resonance, like people are like, this feels so good. It like feels natural. You know, when people meditate, they naturally get down to that breathing rate just on their own. It's just kind of what feels relaxing and good. And you know, it's kind of that case of simple seems to be better. We, we try to match our body's rhythms. Right.
[00:10:21] Speaker A: So awesome. So any other kind of insights that you have had through this? I mean, do, do you, are you in a place to kind of share the data and the results of this? So, so what when we talk about some of the results?
Share, share those with us?
[00:10:39] Speaker B: Sure, sure. Yeah. I can walk you through some of the results. So the first Thing we looked at was just adherence. Like we wanted to make sure people were actually doing the breathing to regularly. Right. Or else we don't have a very valid study. Right. So within plus or minus one second for both of those six breaths per minute breathing conditions, people were 90% following it. So really excellent adherence. For square breathing, only 60% of people were following that within plus or minus one second.
Look at plus or minus two seconds, you get 94%. So people were close, but it was a little harder for them to be right on with the score square. And then 478 breathing was similar. About 70 to 80% of people were able to follow that one correctly. So that does impact the validity a little bit of the study and that less people were able to do it, but it was still pretty high percentage. We're in that plus or minus 2 seconds range. I think that also shows that the square and 478 are just way harder to do.
Lots of people just had a struggle following those techniques.
[00:11:43] Speaker A: I do try and for seven and eight, for a few weeks I couldn't remember, am I on the seven? Am I on the eight? Like, I found that one like, especially like the suggestion I read in some book somewhere along the way or so, like, oh, this is helpful for sleeping or a podcast. And so I was testing it out. I had the same. I probably would have been, maybe I got it close to 80% because I was trying to be tired too. So I'd lose count. And it was like, it was a train wreck for me to try that one.
[00:12:14] Speaker B: Oh yeah, it's hard. Yeah, I've tried it too, and it's difficult. And we even had people wear a respiration belt and follow a pacer and instructions and we would remind them, like, make sure to follow the pacer. And those are just.
[00:12:27] Speaker A: I was going to ask that. So. So with the other, the, the square and the four, seven, eight, you. You did have a pacer for people to follow and they still struggled to get into the right rhythm.
[00:12:38] Speaker B: Right, right, right. And you know, most people were able to do it and be close enough, you know, but yeah, it took longer for them to get into that technique and, you know, just harder and it felt less natural for most people.
[00:12:50] Speaker A: So, yeah, and probably a lot closer than I was without a pacer, just trying to count my breath. So, you know, it's. It's probably. You probably got, in many ways, at least this is my humble outside, like, you probably got pretty good compliance versus somebody who's counting or drawing or what, whatever. Method they were using. You probably, you know, you probably got some really interesting information there about what square breathing is, is, is close. But you know, it's not, you know, just kind of nobody's doing it probably perfectly if they, they don't have a pacer. And even if they have a pacer, it's a little sketchy on the edges.
[00:13:29] Speaker B: Oh for sure. And these are very highly perfectionistic BYU students too. And even they were having a hard time, you know, so yeah, that was interesting. And then with heart rate variability, so we looked at RMSSD and then we looked at the low frequency and we look at the low frequency because people are breathing slowly. So the high frequency heart rate variability is not going to be as accurate.
And we see really significant increases in those.
For example, in RMSSD you see like a 20 unit increase when people are doing the, the 4, 6 breathing. Breathing in for 4 and out for 6. And for people not as familiar with the units, that's, that's a pretty significant increase, clinically significant.
And people, their heart rate variability is increasing a ton on those.
For the square and 4, 7, 8 breathing, we see a little bit of an increase, like a seven unit increase.
But when we adjusted for multiple comparisons because we were doing 10 different comparisons. Yeah, those aren't statistically significant. So maybe like a small increase but not, not really much of an increase in comparatively to the six breaths. They're really not doing much the square and 4, 7, 8 at least for heart rate variability. And I think that has a lot of implications for people's stress physiology and their parasympathetic activation that that's just not happening. Is happening as much in the square breathing.
[00:14:54] Speaker A: Fascinating. Yeah, yeah. I mean it just like totally with that I think like throws into question just so much of, you know, especially in the wellness world, assumptions that we've, we've had for, I mean I think square breathing, I, I heard of maybe like 20 years ago. Like that thing's been around, you know, forever.
When you look at this like, you know, is there, is there any argument for the square breathing or the 4, 7, 8. Could, could you like and I'm just asking speculation right now to be very, very clear. So not, not holding you to this. Are we, are we. Should everybody just be breathing at the six breaths per minute during mindfulness? Is there any argument, I guess, I guess against resonance frequency breathing?
[00:15:45] Speaker B: No. Yeah, there is that. I'm so glad you asked that. So we looked at carbon dioxide levels.
[00:15:50] Speaker A: Yeah.
[00:15:51] Speaker B: Make sure people aren't over breathing. If you're Expelling too much carbon dioxide out of your lungs, you're going to be hyperventilating and you feel a little dizzier and uncomfortable. And if you're really hyperventilating, that can be dangerous. So we wanted to make sure, you know, let's see if people are over under breathing. We hypothesize that people would be under breathing a little bit on the 478 because, you know, they're holding their breaths. But we actually found no change in CO2 levels during square and 478 breathing.
We did find a significant drop in the six breaths per minute breathing. So people would drop about four units, which, you know, typically you want between units of 35 to 45. So if you're in the normal range, you're barely dropping below the normal range. Okay, so people aren't insanely hyperventilating during six breaths per minute, but they were hyperventilating a little bit, which is fascinating because physiologically there is lots of good stuff happening in their body when they're doing these techniques at six breaths per minute.
But people still had a tendency to sometimes over breathe. And during square and 4, 7, 8, they weren't over breathing. And part of that could be the breath hold that they aren't releasing as much CO2 so quickly.
That's my, you know, hypothesis about that. But I think it highlights the need to. Even while the six breaths per minute, it's doing so much good for your body. You gotta make sure that people aren't over breathing, they're breathing out slowly. You're asking them how they feel, if they're feeling dizzy, you're helping them, Even possibly monitoring CO2 if you're doing this clinically. But if people are getting lightheaded to instruct them to breathe a little more shallowly. And I think that's an important takeaway from the study, is someone can be breathing at resonance and still have a tendency to hyperventilate a little bit. So that was one area where square and 4, 7, 8 had the advantage.
[00:17:43] Speaker A: Interesting. Did you find. I know you looked at the extended exhale, like, did. What did you find with. With that?
[00:17:51] Speaker B: Yeah, the extended exhale didn't change anything, uh, part of it. So we had a sample size of 84. So maybe we just weren't powered enough to find smaller differences. But statistically there were no differences between 5, 5 and 4, 6 breathing that longer exhale, um, and even, even inhale and exhale in any of the measures. So it seems like the amount of exhale doesn't matter. And I know that really matches up with Fred Schaefer's recent studies as well, where there's really not much of a difference with the longer exhales.
[00:18:23] Speaker A: Yeah, I know we've really looked at, you know, and I've. I've been nerding out about the CO2 oxygen balance. Healthy, like, fascinating science be behind that. It's where CO2 is. You know, it's not bad. Yeah. We actually need it in that processing. And, you know.
You know, looking at that extended.
The exhale of more parasympathetic activation was. I think a lot of the thinking as well is the exhale, that extended exhale. But it seems like your findings and others are just like, if you get to the 50, 50, that that's okay as well. It does seem like there may be detriments to going 40, 60, but 50, 50, if it's more comfortable for you, you're still getting the. The good HRV impact.
[00:19:17] Speaker B: Yeah. And I think that's key. Just whatever is comfortable for people, Right?
[00:19:22] Speaker A: Absolutely. So any other insights that came out of this for you?
[00:19:28] Speaker B: Yeah, yeah, for sure. There's a few more things. So mood. We measured mood afterwards, after each breathing technique.
We hypothesized people would have a more positive mood in that six breaths per minute.
But we actually didn't see any change in mood for the six breaths per minute. So people. They didn't feel worse, but they just kind of felt about the same subjectively, actually, in us, the square, and 4, 7, 8 breathing people felt worse, so their mood decreased, which is kind of funny. I don't know. Maybe it was just more effortful, or they're like, dang it, that was so hard for 10 minutes. I had to do that.
But their mood decreased a little bit. So I think maybe we only had people do this for one session. Right. So maybe I was gonna ask that.
[00:20:11] Speaker A: How. How many sessions do.
[00:20:14] Speaker B: Yeah, yeah, we just measured it during the one session. People might just not be consciously aware of what's going on physiologically inside of them, at least during that first session. So they might say, I feel about the same. But over time, I would hypothesize you'd see a. A bigger increase in positive mood. I think that's important too. Just that we only measured this during one time period in one study. So I think to really put the nail in the coffin on this, you'd have to measure over time. So, like, over a month. Have people practice these at home.
[00:20:44] Speaker A: Yeah.
[00:20:44] Speaker B: And then what happens to their baseline physiology from you know, pre to post measurement and kind of replicate this study to really definitively say, but as of right now, it seems like six breaths per minute has the edge. And yeah, we also asked people just what they liked and this is a little bit, there's some error in this data because we asked people after they finish the study, so they might not be recalling it perfectly, but about the same number of people said they like square and each of the six breaths per minute techniques. So those are even people liked the square. A decent amount of people.
Everyone hated 4, 7, 8. That was by consensus. Everyone just hated that one. I got emails back, they're like, oh my goodness, that one is terrible. But yeah, some people like the square. And you know, if, if you like it, maybe it could have some benefit. Maybe people like it because they've heard of it before and it has so much publicity too.
That was kind of an interesting thing as well.
[00:21:46] Speaker A: Well, I mean, again, speculation only on my part here too. But you know, working with, you know, I know before we do resonance frequency breathing assessments with, you know, the app, one of the things we want people to practice first. So, so I think your insight on, I wonder what would happen, you know, for, you know, if, if they, if they did this for a week or two, is there some adjustment? You know, do you get comfortable with the breathing and then if you get more practice at it, what, what's going on with the, the, I would assume high or low frequency.
You would see maybe in all of them, but it would be, it would be interesting to see that piece. I don't know what you're doing next semester, but I think that's a good call.
[00:22:37] Speaker B: Yeah, well, and it would be so cool to see over time because, you know, when we measure heart rate variability during slow breathing, that's really giving us evidence that it's working for their practice because that's why we do slow breathing, is we're, we're teaching our body to regulate itself. We're kind of fine tuning all those inner systems of our body and a higher heart rate variability, especially that low frequency is showing us during slow breathing that we're, the breathing's working. It's an effective practice. Right. But over time we'd need to look at changes in like high frequency heart rate variability, normal breathing to see like, is this really impacting people's physiology physiologically long time? And I think six breaths per minute would beat out square because, you know, it seems like during practice it's more effective, but we'd need to study it of course, to find out.
[00:23:28] Speaker A: Awesome. Any other insights coming out of this that you had?
[00:23:33] Speaker B: Yeah, I think, well, a couple just takeaways from this that I think are important is when you're doing clinical work with people like biofeedback, it can be super useful to monitor CO2 because you can be having such a great physiological response and yet still be like hyperventilating. And I think that's an important takeaway from this, and I know that Ina has mentioned a lot as well, is to possibly monitor CO2.
I think if people are using these, I would just suggest going with the six breaths per minute. I think it's going to be more effective for. For most people.
We measured blood pressure too, because sometimes slow breathing can decrease blood pressure. We didn't see any changes in blood pressure for any of the techniques, but studies that have found changes in blood pressure, it's been over time. So that's one of those other things that we'd have to look at over time.
We also had a pretty, you know, our average blood pressure for a student here was 107 over 62. So there's not a ton of room for it to drop either. Yeah, that could be another area of future study. And I hope that people take up some of these studies too and start examining these more and more. I think the more research we get on these techniques, the more informed people will be, you know.
[00:24:50] Speaker A: Absolutely, absolutely. So I would love to kind of see where do you think, you know, you mentioned we've been talking about anywhere else you're hoping to see some of this research go? You know, you really, you filled in a really big gap here, which is, like I said, it got all us really excited about your findings. But what else do you think we need to be doing in this area? What would you like or what would you like to see see done in the area?
[00:25:21] Speaker B: Yeah, I would love to see this applied just to lots of different people.
I know there's tons of groups that use these breathing techniques and there's lots of other techniques we've heard of like the WIM HOF method and things like that that also have very limited research. And I think it would be so cool to see these in different populations. I know the Navy likes square breathing. So being like a Navy seals, if there's similar results, looking at how it affects concentration and ability to stay calm in really tense situations, things like that.
Looking at like older individuals or just, you know, non college students, people that from all walks of life or even kids, just seeing how these techniques affect Lots of different groups and looking over time how effective these techniques are.
And I think that's all really, really important research that could be done or in performance too, with sports, with athletes seeing, you know, what kind of techniques help them calm down and, you know, potentially prepare for things.
[00:26:22] Speaker A: So, yeah, awesome. So I, I love that I get to ask you this question as somebody who's sort of starting out in, obviously with a background, and I know by the time you're getting your PhD, you've been through a lot in life, but, you know, somebody who's excited about this science, you know, at your stage in your career, where do you think?
As somebody who grew up with the technology, way more than I remember when I didn't always have a phone in my pocket. If, you know, you know, you grew up with this in a different way, I. I did. Where do you see sort of the future or maybe hope the future can go? We got AI coming on. We got all this, all this new stuff. Well, when you look at the future of heart rate variability, as somebody who's putting their mark on the field already, where do you think we're going with all of this?
[00:27:16] Speaker B: I just think accessibility. I just want this to be accessible to more people. You know, it's a treatment that can be time intensive. If you're coming in and doing bad feedback at a clinic, the equipment can be expensive. And I would love to just see more accessibility for lots of different people from lots of different walks of life across the world. And I think that AI could help with that, could train people on some of these techniques. I think that that is a cool future area that could be explored more.
Even with psychotherapy, AI is starting to be integrated more into things.
So I think with biofeedback, it could be similar and have more opportunity for people to do things like this at home and not necessarily have to come into a clinic and do televisits. You know, we have different ear clips and things people can use at home. And I. That's where I see it going. I really want to see all of this stuff. It's so helpful for so many people. Just become even more and more accessible to people that people can use.
[00:28:20] Speaker A: I love it. Well, Josh, I really appreciate your work, appreciate you coming on the show to share it. I'm excited for your next paper and to get you back on here, so I appreciate you. We'll put a little bit of information about Josh in the show notes, a link to information on the style study. But, Josh, I just want to thank you for your work. It was great meeting you at apb. And yeah, at your age, I wasn't stirring up any kind of excitement. So the fact, like, the fact that Ina lets me hang around her is just a huge honor. And the fact that, you know, she was so excited about your work is like, I, you know, this, I got to pay attention to this Josh guy here. So I just appreciate you, your work and coming on the show.
[00:29:07] Speaker B: Oh, thanks so much, Matt. Thanks for having me. It was great to talk with you about the work.
[00:29:11] Speaker A: Thanks so much. And as always, you can find show notes and other
[email protected] thanks, everybody, for joining us. Josh, thank you. And we'll see everybody next week.
