Eat Train Prosper

Dr. Mike T. Nelson | ETP#147

Aaron Straker | Bryan Boorstein

Mike T. Nelson, PhD, MSME, CSCS, CISSN, is a research fanatic who specializes in metabolic flexibility and heart rate variability, as well as an online trainer, adjunct professor, Associate Professor at the Carrick Institute, presenter, creator of the Flex Diet Cert, kiteboarder, and (somewhat incongruously) heavy-metal enthusiast.  He has a PhD in Exercise Physiology, and a MS in Mechanical Engineering (biomechanics). The techniques he's developed, and the results Mike gets for his clients have been featured in international magazines, in scientific publications, and on websites across the globe.  In his free time, he enjoys spending time with his wife, lifting odd objects, reading research, and kiteboarding as much as possible.

You can find more from Mike at his website: https://miketnelson.com/

Or his Instagram: https://www.instagram.com/drmiketnelson

Episode Research References:

American College of Cardiology: 
Different types of physical activity offer varying protection against heart disease
https://www.sciencedaily.com/releases/2018/11/181116135957.htm

Adaptations to aerobic interval training: interactive effects of exercise intensity and total work duration
https://pubmed.ncbi.nlm.nih.gov/21812820/

TIMESTAMPS
0:00 - Getting to know Dr. Mike T. Nelson
6:16 -  How did Mike become so “well versed” in different modalities that he can
successfully coach athletes spanning physique to powerlifting/strength sport, to CrossFit and everything in between?
10:45 - Dr. Mike has been an early adopter of the “cardio for health” movement, in a sense. Has he always prioritized “cardio” or has it been a product of working with performance athletes?
17:17 - Concurrent training, General views on the interference effect and how to most productively manage? How better cardio can actually HELP lifting goals? 
23:45 - The benefits of adding cardio to strength training routines
32:59 - Programming for VO2 Max
43:28 - Mjolnir Intervals (a perfect blend of various time domains for VO2?)
51:00 - Breathing mechanics
1:00:09 - Using different breath tests (nasal exhale in my program versus the BOLT test?)
1:01:40 - How HRV plays into this mix of breathing and recovery
1:04:10 - Thoughts on some of the longevity experts’ (Attia, Inigo San Milan) views on using VO2 max and Zone 2 as a reference for CV health and mitochondrial function?

Work 1:1 with Aaron ⬇️
https://strakernutritionco.com/nutrition-coaching-apply-now/

Done For You Client Check-In System for Coaches ⬇️
https://strakernutritionco.com/macronutrient-reporting-check-in-template/

Paragon Training Methods Programming ⬇️
https://paragontrainingmethods.com

Follow Bryan's Evolved Training Systems Programming ⬇️
https://evolvedtrainingsystems.com

Find Us on Social Media ⬇️
IG | @Eat.Train.Prosper
IG | @bryanboorstein
IG | @aaron_straker
YT | EAT TRAIN PROSPER PODCAST

What's up guys, happy Tuesday. Welcome back to another episode of Eat, Train, Prosper. Today is Brian, myself, and we have Dr. Mike T. Nelson on the podcast with us for the first time. Mike, can you please give the episode, or can you please give the podcast listeners a brief introduction to yourself, please? Yeah, no problem. I consider myself probably a human performance specialist. I did an undergrad and a bachelor of arts in natural science, master's in mechanical engineering. PhD was in exercise physiology, looking at heart rate variability and metabolic flexibility. And then right now I still coach clients online. I think I started that in 2012, 13, somewhere in there. I did the coach people in person. for a while at a gym till they filed bankruptcy and thought maybe I should do something different. And then right now I have the FlexDiet certification, Physiologic Flexibility Certification. And I teach for Rocky Mountain University, Associate Professor at the Kerrig Institute. And then I also help out the guys at Rapid Health. And I'm a scientific advisor to Tecton. It creates a ketone ester. a lot going on there. So before we dive in, yeah, and this is something you reminded me when, cause I've been fortunate to meet Mike in person. And I remember this is a question I wanted to ask you then. Yeah. What, as each of your, I can't remember what you said your undergrad was in, but then your master's was in, I believe you said mechanical engineering, and then your PhD is in like exercise phase, exercise science. How, like, take us back just a little bit to your thought process or maybe it was just how you were kind of evolving as a human and your interest shifting to where your different degrees are in kind of what we might consider like pretty different modalities. Yeah, very different. I didn't really have a big plan at that point. I was like, well, I like physiology. This is cool. So my undergrad at St. Scholastica in Duluth, Minnesota, they actually allowed anyone to sign up for anatomy and physiology. And you got to use actual human cadavers. And they got new human cadavers like every quarter. So that was pretty rare. So when I signed up there, I initially was just doing a dual degree program, Bachelor of Arts in Natural Science and a Bachelor of Science in Mechanical Engineering. And as I started doing it, I'm like, well, I don't know. I just take some physiology classes for fun. Got to Michigan Tech and they said, Hey, if you can do two years of postgraduate work, then you can just go in and do a master's. So I was at Michigan Tech for four and a half years. You got done with that almost eight years of school. And I'm like, I'm never going back to school again. That was extremely difficult. Screw that. I'm going to go make money and work in the industry for a while. So I worked in the biomed industry. And then they're like, Hey, you can take classes and we'll pay for them. I'm like, Oh, really? So I started taking more classes at the university of Minnesota. And then I did five, it was probably like five years in a PhD program in biomedical engineering. Although I never did my dissertation or anything in that. And I remember sitting in a class on MRIs and I had completed almost all my classwork, but I hadn't done any research yet. It was hard to find funding. And I'm sitting in there with PhDs in math and physics. And the guy walks in, he's like, Hey, we're going to learn all about MRIs. And we're going to derive all the equations that are used in MRIs from scratch. I'm like, you got to be kidding me. I looked at all these kids are just sitting there frantically scribbling stuff down and my elbow, the guy next to me was a PhD in mathematics. I'm like, do you even know what he's writing on the board? He's like, no. And he's just like, I know this stuff down. And it was kind of at that point where I'm like, OK, I'm either going to somehow finish this or I'm going to jump ship and go to exercise physiology, which I have been thinking about for a long time. But, you know, probably similar to what you guys have done to you put so much time and effort into something and you get so far into it. You're like, oh, man, like this to start over is to be so horrible. I don't know if I want to do that. But I realize at that point, it's either go forward or, you know, switch and burn the ships and do something else entirely. Ironically, I went over to exercise physiology that fall, literally walk in the first meeting and my advisor is like, Hey, we got two new projects, but they both involve math. One's on heart rate variability and one's on metabolic flexibility. And I went over there because I did not want to do any more math. I mean, I could do it, but it was not very fun for me at all. And he looks around the table, there's only five people there. He points at me and he was like, Hey you, math boy, these are your projects now. I'm like, Oh my God, you gotta be kidding me. Dropout's other program has been five years in to come here to avoid math and what do I get is math. But the math wasn't nearly as difficult as what I had been doing before. And it actually worked out really well. Very cool. perfect sense when you put it that way. Yeah, that's awesome. Well, definitely heart rate variability is one of the things that I want to touch on throughout this conversation as well. But before we get in there, just a quick brief background. Most of the listeners will be pretty familiar with your name, as I've discussed throughout the last few months, some of our work that we've done together. I call you my cardio. Yeah, it was great. I call you my cardio coach on the podcast. So that's how people know you. Yeah, yeah, yeah. Um, so one of the things we were working on really closely was, it was VO two max. And, um, it all kind of started just to give everyone a brief background before, you know, if they're, if they're new to the podcast, whatever, uh, we started working together in October after I was on your podcast and we kind of went down the rabbit hole of cardio and discovered that all the zone to work that I was doing wasn't really going to be super effective to increase my VO two max. And then we kind of. paired up, started working on some of these rowing workouts and specifically focusing on the rower and specifically even to narrow that down, the 2K row test, which is a seven to eight minute kind of brutal all out VO2 max effort. And so my first question for you is, you know, we exist in this world of very specialized exercise coaches. It's very siloed into different expertise. Like you have your, physique coaches and you have your strong man and you have your powerlifting and you have your crossfit and you have your endurance. And so we don't often see somebody that's kind of a jack of all trades coach. And so how did you find yourself in a position where you're coaching all of these different types of specialized athletes? Yeah, just kind of give us that background there, because I'm very curious about that. Yeah, I just sort of like a lot of things. You just ran into it because the newsletter I write, which I write for daily, I still write to mostly, you know, Jim bros in their thirties, forties, fifties. But even now it's a little bit less. But even now, 70 % of my online clients are women, even though I write to dudes, which is weird, right? So all the marketing people would be like, what? That's stupid. You should try to write more specifically to women. But I just found that the women I worked with, the female clients liked a different approach and were looking for something different. And with the wide variety of clients I got into, it was just, I realized solving problems and the clients I've always had, there's always something weird. It was like something missing, but no one's been able to figure it out. Whether it's a mechanics thing, whether it's a biochemical thing or who knows. So fast forward over a long period of time. And extremely to you guys, you get a client and you're like, Oh, that sounds good. And then you get into it. You're like, Oh crap. I didn't realize this was the issue. And the nice part about being me is I can literally call experts on the phone and be like, Hey man, I got this client, like what's going on? Uh, or, you know, go back, read all the primary research. And so it just sort of evolved with that. And from a marketing standpoint, it makes like I've hired a high level marketing consultant before, and he just kind of shook his head at me most of the time. He's like, I don't know what you're doing makes no sense. Like you need a niche, like you need to work with only these people and market this way. And I'm like, yeah, but I get kind of bored with that after a while too. And it's hard to quantify in your advertisement of, you know, this person had, so a natural bodybuilder guy worked with years ago, had a right shoulder pain, had MRIs, had everything completely clear, passed every physical. And I sent him a note just half joking one day that I got tired of him bitching on all these different boards back in the day about his right shoulder. And I said, ah, just let me try some stuff. And long story short, he couldn't do left internal rotation with his left lower leg. The second we put his left lower leg in internal rotation, he could press with his right arm with no pain. He's like, what the hell is that? That's so weird. So he obviously signed up as a quiet. And so you just accumulate this sort of weird. weird things, metabolic issues, all that stuff over time. And so for me, what I realized, it probably took me a long time to figure this out is I just like high level problem solving, you know? And I also realized that if I'm only doing nutrition or I'm only doing exercise, unless it's a very high level athlete where I can literally call their coach on a first name basis and be like, Hey, you know, here's what I'm thinking on this or that. Generally don't work with them because it's a pain in the butt. Like, cause it's always the thing you're not in control of that becomes your rate limiter. You know, someone's like, Oh, I hired you for training for body comp. And then you realize their nutrition is a trash bin fire or the reverse. They hire you just for nutrition and their training is just a complete poo show. You know, and I realized over time that I just, I don't, I don't want those headaches. So I'm probably one of the weird people that does all their warmups, all their cool downs, all their, you know, somewhat basic neurology stuff and mechanics stuff, the nutrition, the sleep, the recovery. And doing it long enough, you'll kind of realize where your borders are and where you definitely need to refer out. You know, so I have certain neurologic tests where I'm like, Hey man, like you definitely need to go see this guy because you've been concussed four times and your nervous system is just really, really goofy. And I'm not the best person for that, but you know, go see this person or that person. Yeah, no, that's really interesting. Your breadth of expertise is very impressive for sure. Yeah, yeah, you accumulated much wisdom over the years. So in the most endearing way possible, I'm gonna call the three of us meatheads. And yeah, totally. I agree. And so as a meathead, I was a, call it a late adopter to cardio. Maybe it was because I was younger, maybe it was because I just had a bias and didn't really want to believe in cardio. But one thing that really influenced me into that belief system was a article from the American College of Cardiology that came out in about 2017. And so I have a quote from here that says, While it is well known that physical activity is important for heart health, neither research nor recommendation consistently differentiate between the benefits of different types of physical activity. New research presented at the ACC Latin American Conference in 2018 found that while all physical activity is beneficial, static activities such as strength training were more strongly associated with reducing heart disease risks than dynamic activities like walking and cycling. And so I think I used that quote. I remember reading that back in, I guess it must've been 2018, because that's what it said. And being like, this is the reason why strength training is more important and I don't need to cardio. And I literally started programming strength training plus steps. That was always my prescription. Just get your eight to 10 ,000 steps, do strength training. Whereas it seems like you kind of had your finger on the pulse of this cardio for health movement a little bit earlier. And - we're more on board with that. And so what are your thoughts on the idea of strength training plus walking for general health versus the need to include zone two, zone five, and kind of some of these more specific cardiovascular modalities? Yeah, I mean, I started it probably more seriously, I'd say almost eight years ago. And the thing that kind of put me over the edge was at the time I read similar stuff. I'm like, I hate doing cardio. And I read some studies about, you know, from Vernon coffee about concurrent interference, which I'm sure we'll talk about. And, and at the time I was training for strong man and I was like, ah, screw it. I'm not doing cardio, but you know, maybe 60 seconds of work at some point I'll do medleys if I want to do cardio. And I remember at the time before I was like, man, probably five months out from the meat, just the local meat, walking up the stairs and made it two flights. And I was just severely out of breath because I hadn't done any cardio for like a year. And I remember thinking, wait a minute, am I gotten a lot stronger? Like, are my strength gains like significantly better? And I went back and looked at all my notes, like, am I really that much bigger? And I realized, no, how do I feel? I feel like dog shit lately. Like I'm sleeping all the time and recovery sucks. Like this is horrible. I just got winded off of two flights of stairs. Hmm. Maybe this isn't a good idea. Maybe I was wrong. And then found a bunch of other people. Um, like my friend, Dr. Kenneth J who's done a lot of stuff with the Kerrig Institute for rowing. And to get back to your question, I, if most people in general population just lifted and got him a step count, would they be better? Yeah, no question. Now you will find some genetic freaks that VO2 max stays fine just doing that. Like I've tested a couple of people and I expected their, you know, VO2 max would be dog shit and it was not bad really. But their training was pretty intense. You know, they may have won probably the genetic lottery, et cetera. But I think if you are stuck and your VO2 max is still low or moderate or below where you need, you know, just like anything else, you're going to need specific work in order to bring it up. You know, if you're talking about bodybuilding, if your biceps are small shocker, you're going to need bicep work. Um, so I don't think it's any different than that. And I, I do think it's changed over time with health and with, uh, with lifters, but it's not really that new. If you go back and look like I would do a lot of work with Cal Deeds, like, you know, a lot of high level. So anything conditioning coaches have kind of known this for a long time. Um, and have always kind of, you know, programmed it that way. I think the health. Benefits of it have been highlighted a lot more lately, which is also a really good thing. Aaron, anything to jump in on on there? My only thing that I was gonna add in there is it's the one, as you were saying that my kind of thought process in, as it was explained, is it's like at like your gen pop person, you know, probably, but for someone who's even going to entertain the idea of like actually doing like cardio as well, you feel like you're actually. you're shifting your the tides of the of who the population actually is, right? Because if someone's like, if you're like, hey, for health, you should probably like, you know, lift and do cardio, if they're like, oh, okay, I'm going to be receptive to that. They're already like, you know, an above average gen pop sort of person, most people are going to be like, got it. And then it's like, you out of their mind sort of thing. Yeah, there's a lot of lifters like that too. And you know, one of things I do is I used to argue with people about stuff and over time I finally got wiser and now I just show them data. And I used to argue with people about cardio because I went through the whole thing. I'm like, man, I know this is your rate limiter. Like, is it going to be amazing? And they're like, ah, I just don't like doing it sucks. Like I made it this far. I'm fine, bro. And I just, I would spend weeks and months arguing with people. Eventually one day I'm like, What's the stupid? I should just do an assessment and see where they're at. So I would do their assessment. I would give it to them either like in a population that's athletic or just against general population numbers. I'm like, Hey, you know, here's your VO2 max. You are at the bottom 20 % for a general population. The general population is pretty damn unfit. And that's all I would do. And I'd send them the graph or I talked to them in person. That was it. I just shut up. And 99 % of the time they're like, Oh, I didn't realize I sucked that bad. Oh, well, how do I make it better? Oh, cool. I'm so glad you asked. You know, instead of trying to argue with people all the time, it doesn't always work, but more often than not, if they're somewhat like you said, competitive or they want to get better, then they realize, oh, okay. Yeah, okay. I'm on board now. Yep, that makes total sense. So similar to kind of the bias that I had around strength training and walking and kind of the avoidance of cardio, I think part of that was supported by the literature at the time on concurrent training. And so it seemed like right around that time in the mid 2000 teens, there was a lot of research talking about the interference effect and how that can be problematic if you have, you know, specific goals in one or the other. And so can you just briefly kind of take us through anything that you can reference from the literature or your own experience regarding concurrent training and how that has kind of progressed through over the last five to 10 years? Yeah, so concurrent training is basically, can you do two modalities at the same time and get the highest level results? At the high level, concurrent training, there is an interference effect, right? You don't see pro bodybuilders winning marathons, right? You just don't see the classic endurance athlete competing in strength and power sports and doing really well. Vice versa, you don't see the reverse. So on some level, it is a true thing. And for the listeners, the reason that is, is if we take a simplistic view, which this is a little bit overly simplistic, but you have generally two types of fibers. You have your fast -touch fibers and your slow -touch fibers. And there's all subsets and hybrids in between and everything else, depending on what classification you use. These slow -touch fibers generally are more aerobic. My little air quotes here, meaning they have to use oxygen in order to create energy. These are the ones you would more preferentially use if you're doing a lot of aerobic training and you're going to go run a marathon, et cetera. And the reason they're smaller is that they're wired differently. But one of the main reasons is that you have to have oxygen diffuse into the fiber, something called the Krogh cylinder model. If the fiber gets literally too big because diffusion is this passive process, the inside part of the fiber will literally die. So there's a hard -coded limit based on the diffusion of oxygen of how big that fiber can actually get. But because it's using oxygen, it has the ability to produce force over a slow rate for long, long, long periods of time. If you go to your fast -switch fibers, those are your classic, my little air quotes here, anaerobic fibers. They don't necessarily need oxygen to, quote, survive. Yes, oxygen is a sort of backup. It does work. You do need it. those fibers can get a lot bigger because there's no rate limiter of diffusion of oxygen into the fibers. So knowing that, I probably over extrapolated that early on to be like, yeah, that's why aerobic training kills all your gaits, man. Like it's just gonna make all your fibers weak and small and then you don't want that. But if you look at the literature, the amount of work you would need to do to see an effect is... astronomical like you read some of the studies where there was a true interference effect in people who were moderately trained they just literally beat the ever -living crap out of them with endurance stuff and they did lifting on top of it you could even argue maybe their sleep wasn't great maybe their collars weren't controlled all that kind of stuff so at some level there is a interference effect will most people probably run into that no the caveat with that is if your goal is maximal speed and power, would I necessarily have you do a 40 % of just moderate cardio after your speed and power days? No. But for most people, you don't really need to worry about it. Having said that, I do still tend to program aerobic stuff in the morning, starting training in the afternoon. I will try to separate them a little bit. The molecular underpinnings of aerobic stuff will last four to six hours in general. Strength training stuff, as we know, you guys have talked a lot about this, could be 24, 48, potentially 72 hours. You still see changes in muscle protein synthesis, other effects, depending on your training status, what you did. So my bias is I will program aerobic stuff usually earlier in the day, especially if it's moderate level stuff and strength training later. Having said that, if someone is even just moderately fit, they're super cramped for time, yeah, I have programmed them one session after the other. Is it? quote unquote, perfect or optimized? Probably not. But is it something they really need to worry about it? If the option was, hey, they're not going to do any cardio at all. Shit, like doing stuff after your main lifting is way better than not doing it at all. Right. And that's the part people forget. It's like, what are you comparing it to? What is the context? So we can, you know, debate stuff about moderate or rubby training directly after strength training. Yeah, maybe it's not best. Like you're pulling the organism a little bit too different directions. However, if that was your option versus, oh bro, I'm not doing any cardio at all. Like just do the cardio first. Like do the exercise first. You, you're still going to get a lot of benefit. Yeah. If you scale all that up super high, will you run into issues? Yes. However, I think usually that main issue is people just don't eat enough at that point. Um, but if you even, you know, cover all those recoveries, good, you max out all that. Yeah. At some point you are going to run into an interference effect. However, It's still a small percentage. It's not like you destroyed all of your gains and you're never gonna get bigger. Again, most people who, especially lifters, like if I run into a legit person who I think has an interference effect who's primarily lifting in like 15 years, no, I don't think so. Does it exist? I equate it to over training. Like is over training a thing? Yes. Is overtraining syndrome a thing? Yes. Will most people who lift ever have to worry about overtraining syndrome unless their lifestyle is a complete pooh show? Probably not. Doesn't mean it doesn't exist. It's just out of all the things you want to worry about, that's like super far down the list. Yeah. No, that's great. I think that what we're basically hearing is that as long as you're not taking it to the extremes and you don't have like really strong goals in one direction or the other, endurance or strength training, that you can get 95 % plus of the benefits of each by doing them together in kind of an intelligent manner. And so I also know that there are benefits of doing cardio that can actually enhance your strength training or your physique pursuit. So can you briefly touch on kind of some of those benefits as well that people may experience if they start adding cardio into their strength training routines? Yeah, and that's the main way I sell it to people because a lot of the people I work with come in and they're like, Hey, I, everything's going good, but I can only train like three days a week. I love training. I want to get better, you know? And at some point we could argue about hypertrophy mechanisms and everything else. My bias is you just need to do more high quality work up to a point. Like if you're only training two days a week or three days a week for 45 minutes and you're relatively in shape, you've been doing this for a while, you're not a newbie. I think if you could train four sessions, five sessions, as long as you can maintain that high quality work, you're going to get a better result. Is it going to be astronomically better? You're definitely on that flattening part of the curve. And most of the time, I think they're limited by their aerobic ability. So if you think about in the gym, You go in and do a session like you do a hard session of deadlifts and you're kind of a little bit out of breath. That recovery period is primarily an aerobic event. You're primarily using more fat for fuel. You're primarily trying to get oxygen into the fibers themselves. You're running your aerobic system to replenish the ATP, the energy that you spent doing that air quotes anaerobic event. There is no real true anaerobic or aerobic. It just makes for an easier explanation. And what I find with a lot of these people is if we have them rest just based on heart rate, which is an okay method, it may take them three to five minutes for their heart rate to get back down before they can do another set. So if we could reduce that to say two or three minutes or even a minute and a half, that's their aerobic system is primarily that limiter. So one, their density of what they can do for training usually goes up by quite a bit. So that also then saves them time. I got that clients where we equated out. the amount of time they were spending before and after doing cardio, like literally it came out to the same amount of time per week, because we could push the density of their training better and they still were doing some aerobic stuff on the other days. And then if you extend that out to day to day recovery, what is one of the limiters of day to day recovery? Again, shocker, it's your aerobic system. Like we're just sitting there hanging out having this discussion. It's primarily your aerobic system that's actually producing the ATP. The example I use for clients is that I sound old now because nobody remembers like the little three cylinder you go cars they had for a while. Maybe you guys do. Maybe not. So I equate to them like, hey, if you're trying to drive around a little three cylinder you go all the time. Yeah, you can redline it and get to the grocery store faster. But the cost to do that is going to be pretty high. If you've got a fancy Lamborghini, it's a V10, V12, whatever. You can get to the store really fast, but the cost that exerted upon that engine is very minimal. Why? Because you have a massive engine. So you are literally walking around like sub max of everything else. Another test is like the NFL combine test. So do 225 bench press as many reps as you can. If your max one RM for bench press is 245 versus Bob, who's like 405, I don't put my money on Bob like all day. Right? Because 225, if your max is 405 is way sub max than if your max is 245. So if your VO2 max you're walking around is 25, like everything you're doing is a much higher percentage of that. So your background stress that's taken away from your ability to recover is higher. If your VO2 max is 50, now that's way sub max, like doing everything else, it's much easier for your body to recover. Last part is most people generally report that their energy feels a lot better. And if we look at their heart rate variability, we look at other markers of stress, they can handle a lot more insults in different areas and get back to baseline faster or their recovery is a lot better. So usually when people talk about recovery, they talk about great things with nutrition and sleep and stress reduction and maybe cold baths and sauna and everything else, which is cool. But I think the big limiter they miss is, Again, if your VO2 max is 25, you know, like a field mouse, to me though, a lot of those things are just like icing on the cake. Like you just need to build a bigger engine first. Yeah, do all those other things. It's helpful, but that by far and away a lot of times is your rate limiter. Once you get that up, then everything else is more sub max, just like lifting. You know, at some point, even if hypertrophy is your only goal, like, you know, again, a lot of the natural guys I know, they're all pretty damn strong. Like are they as strong as, you know, power lifters? No. Like compared to most people, they're pretty strong. But at some point getting stronger will allow you to do more reps at a higher weight, which again will allow you to stay in more of that hypertrophy specific zone, which is a massive zone at this point. Yeah. So it sounds like with better cardiovascular conditioning or aerobic fitness, you're kind of walking around day to day with a more parasympathetic state, which allows your body to facilitate recovery and adaptation in a more streamlined manner than it would if you're not as aerobically fit. Yep. And the last part, which the literature goes back and forth on this, but I think it probably is a real event. There is some benefit to capitalization. So just, just changing the architecture of the muscle to get more blood flow to it. If you look at a lot of the old school, like Russian stuff on recovery, pretty much all of us blood flow based, like what are you doing? Contrast therapy, sauna, walking, moving, Normatec boots, whatever. Almost all of it is just based on getting more blood flow to the muscle. So if you can have more blood flow there, you can literally create more vessels and structure to the muscle. I think that's going to be a benefit. Like when does that happen? How often does it happen? I don't know. Literature is all up in the air, but I have seen when people start doing aerobic stuff, this big inflection point at about six to eight weeks. Like you won't see a lot of movement like, eh, eh, eh. And then like the run the week seven, they're like, man, I don't know. I just feel better. Like everything's moving better. Like there just seems to be this weird uptick. And I can't find the study, which I could have completely made it up that there was some old Russian research that showed that the blood vessels grow from opposite ends and that around the six to seven week mark, they sort of meet up. And then you have this increased exponential in blood flow. Again, I can't find that study. I could have completely made the entire thing up. It's been bugging the crap out of me. So if anyone finds that study, please send it to me. But it kind of makes sense, at least mechanistically, what we see at that point. It's sometimes hard to get people to that. So like, hey man, I'm doing all this work and I don't know, I just don't feel that much better. But it's like anything else, like hypertrophy. Like nobody even, you know, people have been training for a while, you don't go to the gym and start doing more bicep curls and go like, hey, week three, my biceps an inch up. It just, you know, physiology doesn't move that fast. Yeah, cool. Aaron, anything before I shift the conversation here to VO2 Mac stuff? No, I just, I think for the listener out there and for myself as well, that was a very, very profound kind of segment that I hope people don't kind of like skip over the fact that like as your VO2 max is higher, like everything else you do is then less taxing on your body. And what I think's really funny, Mike, is you use that example of like the three cylinder car, you know, going to the grocery store versus a Lamborghini back in like the, you know, literally dead smacking COVID where all the like rental cars were places were out of cars and stuff. I ended up with a literally a three cylinder. I don't even remember what it was. It was like a go -kart sized car and we were living in Salt Lake City at the time. Oh my God, it was so small. And we took it up into the mountains because we'd go up into the mountains hiking. And because the engine was like so small and we were like up in the mountains, I literally had to like redline it to just to get up the road. And I burned an entire tank of gas. just going from like literally 20 minutes to the top of the mountain. And then I was panicked because I thought I was gonna run out of gas because of the gas I was on, I had to coast all the way back down, but it was like, it was such a perfect example. Like because the car's capability was so low, I had to push it so hard. I literally smoked an entire tank of gas just driving up the mountain. Yeah, we had a similar situation going to my buddy, Dr. Ben House's place at Flow Retreat Center in Costa Rica, where we put five rather large mammals in this small vehicle. And this was before he had his place there. So it was a different place. Same thing all the way at the top of this, you know, big mountain. And so I'm driving and they're like, why are you going so slow? And we're doing like 25 miles an hour. I'm like, I have this thing floored. And it's like, it's like. That's awesome. Okay, cool. So jumping into quick section here on VO2Max and the training around VO2Max. So I assume you're familiar with Steven Seiler and some of his research. Do you know this guy out of Norway? Yeah. So Steven, I've followed a lot of his work. He's done a lot of... Yeah, he's done a lot of work comparing four minute intervals to eight minute intervals to 16 minute intervals. He has a few studies that actually do this. And so there was one here, adaptations to aerobic interval training, interactive effects of exercise intensity and total work duration. And we have a pub med link for that that we'll drop into the notes. The conclusion of the paper basically stated, that the four by eight intervals were more effective than the four by 16 or the four by fours, which I think is in contrast to what most people think of as the four by four as like the premier interval to be used for increasing VO2 max. And his hypothesis was that accumulating 32 minutes of work at 90 % of max heart rate induced greater at a. adaptive gains than accumulating 16 minutes of work at 95 % of heart rate despite lower RPE. And then the 16 minute intervals were at 85%. So it was 85 % for 16 minutes, 90 % for the eight minute intervals or 95 % for the four minute intervals. And of course the four minute intervals only allowed 16 minutes of time in zone, then 32 minutes of time in zone for the eight minute intervals and an hour and four minutes of time in zone for the 16 minute intervals. They were all effective at increasing VO2 max, but specifically the four by eights appeared to be the most effective. And so I found that interesting just because the four by four seems to be the most popular one that people like Peter Attia and others are promoting as, you know, do this for VO2 max. I think it was a Norwegian, they call them the Norwegian four by four or something like that. But then the other thing that I've noticed throughout reading research is that there's also a lot of studies showing that, things like Tabata's or 3030s or 6060s and these other like significantly shorter intervals are also very effective for VO2 max. So what are your thoughts on that? How do we make sense of all these different ways that you can go about kind of increasing your VO2 max? Yeah. So one of the misnomers of VO2 max is that people think you just do any cardio and your VO2 max goes up. Like, yeah, if you're untrained and your VO2 max is horrible, sure, anything will work. Right. So newbies can lift soup cans, probably get bigger, right. But at some point that's going to max out pretty fast. So once we get beyond that, you need to be, in my experience and looking at the literature, probably relatively intense, like what percentage of heart rate, there's other ways to market. 85, 90 -ish percent, you know, somewhere around there. So I equated to, if you want to get significantly stronger, you probably need to do a fair amount of lifting above 85%, right? You probably need to do those low rep stuff. You need to put some heavy weight on the bar in order to get stronger. So with VO2Max, I equated it to the same way. You think of VO2Max like the 1RM for your aerobic system. In shocker, the same principle holds pretty true. Now, how much time do you need to spend there? Oof, that's all across the board, right? So in that study, which is cool, I wonder if it is as much the effect of intensity versus the, like you said, the time in that area. And what I find is that it's generally the amount of time you can accumulate in that area. So just like lifting, like how much high quality work can you do? And the biggest mistake I see people make is, They just, you know, went out super hard. Ah, let my nuts suck on fire. I did these two intervals. Woohoo. Look at me. My VO2 max is going to be amazing. Maybe not like you need to accumulate more work. And then also if we look at the output of let's say interval one versus interval six, if interval six is like 30 % of your first interval, like you're not training the same thing, right? A lot of people want to do these repeats that are very, very difficult with incomplete rest. but they're not really recovered back to baseline again to start. And if you look at the quality of the output, it just tanks, right? So now you're not working that specific thing that you want. So when I start programming for people, depending on what their level is, a lot of times I do almost complete rest. Like let's hit two minutes or three minutes or four minutes or five minutes or six minutes. And we know what percentage you need to be. We need some output on a bike, maybe running, we can get GPS, the rower. And then you're going to rest almost completely. We're let your heart rate come down probably below a hundred. And then you're going to go again. Can you get back to almost, you 5 % of that output again? Cool. All right. Let's rest completely. Could you do a third round? And once your performance tails off in a perfect world, you'd actually be done right before that. So that allows someone to program without knowing your exact capacity. That still accumulate that high intensity time. So you could start with a two minute interval, right? So I, you know, whenever you publish any program you've ever done online, it's just a disaster. Cause no one wants to talk about the context. So I've published some programs in the past where I've had someone just do 120 seconds, two minutes at high output. They only did two intervals. And they're like, you're an idiot. What are you doing? Haven't you read any literature? Don't you know it's closer to four minutes and eight minutes and you need to accumulate 32 minutes and all this stuff. I'm like, yeah. Then we did the third interval, their work output was such dog shit, like there's no way they could do it again. And if we went to three minutes, their performance dropped off so hard at minute two and a half that it wasn't productive. So we had to scale them back to their current capacity. It doesn't mean that we'll never get to four minutes or six minutes or longer intervals. It's just they, they can't handle it yet. And if they do, sometimes we will do longer intervals and literally just do one. So you want to make sure the quality is there first. And then over time, you can progress. You can actually get to the point where you're doing incomplete rest. With the really short ones, yes, you can see some increase in VO2 max. Let's take the Tabata study. God knows I got to write this article because this question comes up all the time. You look at the actual Tabata study. So what did they actually do? So very, very high intensity, literally incomplete rest. Like they were resting less period of time than they were working. which for people to do high output stuff is incredibly difficult. I think they were doing 170 % of their VO2 max. So they are way above VO2 max. Did they see cool improvements? Yes. The study was set up so that they could not complete all the intervals though. If you look past about week three, I think, I'd have to look at the actual data again. Their VO2 max didn't increase any more after that. So there is, I think, some short -term benefits from that. However, that study has been completely bastardized to like Tabata 1RM pre -truck hurls and all this other stuff where swimming Tabata's, you know, like run, even running Tabata's, most people just don't have the sprint integrity to run that fast. Like I put people on a rover, we'll baseline their 2K. I'm like, okay, let's just do one interval at 170 % of that number, right? Cause you can figure out what that power is. Maybe they can crank out one interval, like even with complete rest, they can't even get a second one that's close to it. Well, it makes me think that you're gonna rest for 10 seconds and be good to go again. Again, you have to keep that level of output in order to get some of that benefit. And yes, I have done, I stole this from my buddy, Dr. Kenneth J. So if you wanna put like a high end spec, what I've done is back of the envelope is, if you can do a high output on the rower, which is based off of your VO2 max, and you can do 30 seconds on and 30 seconds off and you can hold that high output for 10 rounds with only maybe a 5 % drop, that is pretty damn badass. Now is that a elite level Olympic rower status? No, but for most people that is incredibly hard. Now could you suffer your way through 10 rounds and hate your life? Yes, most people have done that. Their output is literally half of what they started. Again, that's kind of what I've been as like the high end of the high end, like one -to -one work to rest ratio, but you can recover within that 30 second period to go again and do it again. Soccer, what do you need to do that? A high level of aerobic training. So you won't see people with a low VO2 max pulling that off. If they do, their output is like 85 watts or something. This is like, yeah, who cares, right? So again, I remember having this talk with Cal Dietz years ago. I was helping him write up the Triphasic 2 book, which we're still working on. Story for another day. In his office, he's writing all this stuff on the board for like 45 minutes. At the end of it, I'm like thinking, how the hell am I gonna write an article about this? Like, there's no one, you know, this is an article. I looked at him and I'm like, okay, so you're saying do the highest quality work first and then repeat that. He kind of looks at me and he's like, yeah, yeah, that sounds right. Oh man. You know, then you need to know, that's why I love using the rower. You automatically know your output of everything that you do. And some days, if it's not there, maybe you go another round and it's still not there. Cool. Just, I don't care what it's programmed. Just shut it down and go home. Like you're just digging a bigger hole for not a specific adaptation at that point. It'd just like training. Like how many people do junk reps in the gym? We could have an argument about what that is. At some point, the volume you're doing is just not. helping you reach your goal and you're just digging a bigger hole at that point. Yeah. It sounds like if you're doing like 30, 30s or 60, 60s or something like that, you really just need to pace them out so that your first interval is about the same output as your 10th or your 12th or your 20th or whatever it is. And so it might feel easier and you'll see that trend line kind of increase in RPE across the workout, but you're not necessarily having higher output as far as Watts go or like, yeah. So one of the cool things that you did with me, on the rower. And I assume this could be extrapolated out across different cardio modalities too, is the, and I'm going to say this wrong, mejolnir intervals. yeah, it's Thor's hammer. Okay, well those were incredibly awful and they played on this short rest, yeah, they played on this short rest sequence. So basically for the listeners we went 30 seconds hard, 30 seconds rest, 60 seconds less hard but still hard, 30 seconds rest, then it was like a minute or a minute and a half and then 30 seconds rest and then it was like two minutes and then 30 seconds rest and then maybe it was like two and a half or three minutes and. then you'd rest five minutes or something like that. But basically only 30 seconds rest between these intervals where the effort starts at 170 % of VO2 max. And by the end you're at 75 % of VO2 max for the two or three minutes or whatever it is. But because these rest periods are so short, even the 75 % max of VO2 max interval was still super challenging because you're already fatigued going into it. So I thought that that was just super cool. I mean, it was miserable by all accounts, like one of the worst things that I've done, especially when you increased it to four rounds. So it took me like just under an hour to do that. But yeah, where did those intervals come from and why are they so effective? Yeah, so that's all I blatantly stole that from my buddy, Dr. Kenneth J. He's got a great book called The Cardio Code. So look up his stuff. He's the one who got me into rowing via the Kerrig Institute. And I never used a rower much before I had played around with it. And I was like, but I realized with lifters, it's great because you get output and it's a full body. You can do everything from power to aerobic stuff on it. It's easy to get data and it's no impact. And. most people can figure out how to roll. Like, are they gonna be elite level rower in two sessions? No, but they'll be effective enough that they're not gonna really hurt themselves or damage themselves. So it's the curve to learn how to do it isn't super high. So I think that was adapted from some Scandinavian research that looked at, there's something called, you can do a bio-energetic profile. I'm blanking on who the researcher is, I'll think of it. And. You just have people do like a very short 100 meter the next day. You'll do we did this with you, right? So you're 30 second wind gate, 60 second wind gate, 180 second wind gate, which is a three minutes hard as hard as you can, which is miserable. A 2K and then a 20 minute. There's also the hour of power, which I don't do it to anyone to 60 minutes. And from that, you can then map out, are you really good at the strength and power you stuff or this aerobic capacity around 20 minutes to kind of cap out there? And what he's saying is that with that specific program, anywhere from a 500 meter to a 5K, like most people will improve. So what are you doing? You're stacking the high output, high intensity stuff first, but it's very short. You're dropping the intensity a little bit and you're going a little bit longer, dropping the intensity again, a little bit longer. So you're literally stacking fatigue on top of itself, which allows you to use these very short recovery periods. But then that's a block of five intervals. And then you have, like you said, three to five minutes off. So your goal is we know based on your 2K, which is 100%, we can then program these outputs that you should hit. So you get everything from high power output to moderate aerobic stuff too. But you're still doing it in a way that you know what your output is. And then once you've kind of completed those, you've got like a complete full rest period after that. And if you scale up to doing, I think I did the math one day, like five rounds on that, I want to say it's what 7 ,500 meters, I think. And if you just sat down on a rover and did 7 ,500 meters, like your overall quality will just drop off pretty hard. So it's kind of a cool way of, I would say, entertaining lifters also, because you always got that next thing you're looking at, the next thing, the next thing. But you end up getting them to do this high quality output over. the course of time. And like you said, for people who've ever done this, you set it up and you're like, ah, one round. Now that kind of sucked. That wasn't bad. Two rounds. Yeah, you know, it's okay. You know, it wasn't that bad. I think this is going to be all right. Like round three, you're like, fuck, I hate my life. You know, round four, you're like, oh, look, white buffaloes in the sky. I want to die. I hate you. Like the fifth round, you're like, oh my God, please make this thing. And this is the worst thing I've ever done in my life. Yep. That's literally how I felt. I mean, it was awful. But I do agree that having those kind of built -in rest periods and that kind of the next thing in sight, and then you know you have that like four, three to five minute rest at the end. I just love those. I mean, I hated them, but I thought them extremely effective. And so I appreciate you kind of introducing me to those. Yeah, they work great. And it's a thing where you also have to take the psychology of crazy lifters into mind. Because if I just programmed you to do 7,500 meters in a row where you're like, screw you, you're fired, this is dumb, I'm not doing this. Or if you did do it, your output would drop off like so hard. Yeah. right, cool. I wanna shift into some breathing and HRV stuff. Aaron, anything on VO2 max before I do? No, except for it. When, when, when conversations with, with this, I'm always like, ah, maybe I'll do some of that. And then after the end, I was like, no, I'm not doing that. I'm not adding that into my life right now. It's a hard pass. on the bike, bro. Do it on the bike. You got it. Um, yep. VO2 max was, your 2K and then post and then the fact that you did six weeks and then you said we need to take a break. Which is very typical. Yeah, I, it's mentally, man, it was psychologically more than anything. It's just, yeah, it's just so hard to go there, to get up and go there and do all the training that goes into going there. It's just, it's so daunting. Yeah, and that so for listeners, we said he wanted to increase his VO2 max. We primarily use the rower. He's like, yeah, I want to do this. So we blasted him for six weeks and I don't know. What do you cut? What's 15 seconds or something off your 2K? I think, is that right? Yeah, well, yeah, it was a 25 seconds from the very beginning to the, to the end, but from when we actually started, yeah, it was 11 seconds, but those were big 11 seconds. It went from seven 14 to seven Oh three. Yeah, and that's a huge difference from 714 to 703. And then also for the listeners, shocker that once we hit the goal, it's like, oh my God, I can't handle that anymore. Let's go do something else on my own. Right. Which same thing with lifting. Like if you've got a big goal you want to hit, like, you know, I'd much rather people take a six, eight week period and just do the best you can and see how close you can get. And cool. You got close to the goal. We made the goal. Great. You want to shift gears and do something else? Cool, like I think once you're at a moderately advanced level, that's kind of what you have to do because the days have gone by where you just go out and leisurely row 20 minutes and expect to shave 11 seconds off. Like that's not gonna happen. Right, no, 100%. Yeah, it's just, it's very all consuming. Cool, so breathing is something I've actually been really interested in recently. I've been listening to a lot of things from Brian McKenzie, Patrick McCown, among others. And they talk a lot about breath rate. How many breaths are we taking in a minute? And they specifically talk about breath rate during sleep. And so this is now something that I've been paying acute attention to on my own because my Apple watch actually tracks my breath rate while I'm sleeping. And I'm now keenly aware that I over breathe while I sleep, but I don't seem to breathe as fast during the day. Like just sitting there doing computer work, I'm usually in that 10 ish, 10 to 12 breaths per minute range. But when I'm sleeping, I tend to be between 14 and 18. And the numbers seem to show that when you're sleeping, you want to be in that 12 or less range for the most part, um, to kind of control CO2 and all these other parameters and stuff like that. And, uh, yeah, so I've just been a little, uh, I guess, unsure of why I'm breathing so much while I'm sleeping. I mean, I'm, I'm mouth taping, so I'm breathing through my nose. I'm not sitting there panting and, and mouth breathing. So it's just been really interesting and you know, what are your thoughts on the breath rate thing and how impactful is that for general human health and also for output of cardiovascular ability during, you know, aerobic exercise and stuff like that. Yeah. The short answer is I think it's super beneficial. So when I got into this, I read Patrick McEwen's book when it first came out. I read a lot of early Boutteco research, which is what his book is based on. And honestly, at that time, I just, I didn't get it. He's like, yeah, at least people are walking around over breathing. I'm like, what are you talking about? Like the breath rate's fine. You know, and then over time I started doing a lot of stuff. So I started using the bolt test from there with clients. And then I realized, I think higher level clients just cheat their ass off because one of the things you have to, the marker for the end of the test is when you first feel the sensation to breathe. And so I started doing it with the clients in person. I'd seen them like, you know, basically almost turned blue and passed out and they're like, no, bro, that was like my first time I felt the urge to breathe. I'm like looking at your face. I think it was like 20 or 30 seconds earlier, you know? And then Brian McKenzie has his exhale test, which I switched everyone over to just to take a nasal. Breath and then how long can you do that nasal exhale? I'm human Andy Galpin to publish some cool research on that So that's kind of a way to calculate your your baseline and when I started doing this clients Got with me five years ago when you first came out with it six years ago It was weird like some clients were really good and some were horrible and then with the advent of you know aura and a Garmin and the ability to look at respiratory rate at night. I then realized oh Now we have a window into what is your physiology doing when it's completely unloaded. And I started seeing these high breath rates, like mine for a while was 16, 17 breaths per minute. And if you look in physiology, they'd say, well, that's kind of normal. But what you realize is that if you're breathing really fast at night, the question is, why are you doing that? And your body is used to a certain level of CO2. and that CO2 level is plastic because it's regulated by certain parts of the brain stem, meaning that you can change it over time. And a lot of people don't realize that CO2 is a primarily driver of breathing. Oxygen is the backup system. So when you're holding your breath, your CO2 is accumulating because you're not breathing, shocker, and then that triggers your body in order to breathe. At night, you're breathing too fast, meaning your body is trying to regulate this level of CO2, but it's kind of at the wrong setting. It'd be like setting the thermostat in your house to the wrong setting. So you're optimizing, you're trying to move around this set point. And when I started looking at it closer, like people who had a lot of reported ADHD, like, oh, look, squirrel, like people who were just, you know, completely on the sympathetic side, we'd look at resting heart rate, we'd look at their HRV. Most of the time, but not all the time, the respiratory rate would be super high. Then we're talking to Andy about this too. And the thing that it finally made sense to me was the ability to look at it at night in a measurement where they're unloaded. And so they're not having any conscious control over it and they're not cheating. So we can look at this data and see where they're at. So if they are over -breathing, what you want to do then is you want to change that setting of their CO2. And what I've realized is the best for this, again, this is from Brian McKenzie's stuff, Emily Hightower, Andy Gilpin, all these guys. Some breath control on walking or moderate aerobic stuff will make a huge difference. So you'll have clients where you'll spec, okay, I want you to breathe in and out over two seconds, which is pretty easy. But you'll hit that point just doing zone two stuff where it's hard to stay at that area. Like you want to go below it or you want to go above it because it's uncomfortable. So you're building up more CO2, but you're not changing it. You're not trying to get rid of that CO2 right away. And over time, what this will do is change that setting of those chemoreceptors in the brain. And that'll then down regulate your breath rate. And when that happens, people then report, Oh yeah, my sleep is better. Like I don't feel as ADD, like I don't know squirrels, like, eh, whatever. It doesn't matter as much. Mm -hmm. I think those people were on that sympathetic side. The first thing I look at is what is your aerobic development, VO2 max? What's your resting heart rate? What's your HRV? And then I'll look at what is your respiratory rate at night? Because those things will tell me what areas we need to target. If your VO2 max is dog crap, any benefit in that is gonna be a huge improvement. If your resting heart rate is too high, yeah, VO2 max probably again. If your respiratory rate at night is just high, but your VO2 max is good and your HRV is okay, then I'm going to definitely target some type of breath control with walking or zone two stuff, trying to get you used to that next level of CO2. Sometimes an air quotes, it's called a CO2 tolerance so that we can down regulate that over time. Yeah, that's really interesting because I actually fall into that category of somebody that has an extremely low resting heart rate, like in the low 40s. My HRV, which I want to get into next, is quite good as well. And I've just recently switched to the chest strap with the Elite HRV app because what I realized was that my Apple Watch... was giving me these super high bloated readings. And I only just realized it's because it's calculating it based on SDNN. And we'll get into this. Whereas the chest strap is using RMSSD, which is pretty much what the Aura and every other device out there uses RMSSD. So I've had this history of people on the internet in DMs and stuff being like, dude, your HRV is in the 200s. How's that even possible? And I've realized it's because the Apple Watch uses SDNN to calculate it, which just... gives it a higher number. But regardless of that, my HRV on the one to a hundred scale is in the high seventies, which is an RMSSD of like 170, 165, something like that. And my resting heart rate is low. My VO2 max is, we don't exactly know. It's not awful if I'm rowing a 703 2K. And so yet I'm still breathing. I'm over breathing at night and I can't figure out how to stop that because I think it's also impacting my sleep. And so this was really insightful. And so I'm gonna actually talk to you off air at some point about the breath rate control during zone two and walking and stuff like that. So I can start trying to target that a little bit, but because we only, yeah, yeah, yeah, go for it. Make sure you go through a period. So watch your breath rate during your next deload or your taper because breath rate will go up based off of a stressor. And it's one of the first things to change. So some people may have a higher respiratory rate, but they just may be overreached. I'm not saying this is you, but I'm saying I've had that with a few clients where we just deloaded them for sometimes like 10 days, their respiratory rate completely normalized. So that tells me it was response to an acute stressor, not necessarily the chemo receptor stuff we talked about. Second thing, look at respiratory mechanics. So I use a lot of RPR, reflexive performance reset. Any pickup you can get in respiratory mechanics and rib cage expansion, most of the time respiratory rate will go down also. If that changes, then you're probably okay. So those are the two caveats to look at too. Okay, cool, noted. I also had a question on here to discuss the difference between why you use the exhale test and the versus the bolt test, but you addressed that. So the one thing I just find very interesting on this is so I've been using both since you introduced me to the exhale test, I feel like you can cheat both of them. Like, yeah. So the exhale test is interesting because you can exhale really, really, really slowly. And eventually you can get to a point where you're almost doing a bolt test, but you still can convince yourself that you're still exhaling, but you don't actually have much exhale left. So I thought that was interesting. As far as the bolt test specifically though, when you talk about the first desire to breathe, I think it's very apparent when your diaphragm starts doing weird things. When you're doing the bolt test and then you kind of feel this like little, this little like hitch in your diaphragm. To me, that's the point where I'm like, oh, that's the end of the test right there. Yeah, your diaphragm starts spasming like you may have went too far on the test. Yeah, yeah, exactly, exactly. But you will find that you generally get a much higher score on the exhale test than you would on the bolt test, right? Yeah, they're different scales and they're just different things. The exhaled test, you're looking to more of that eccentric control of the diaphragm. So you're trying to get at some of the chemoreceptive stuff, but also some of the mechanics type stuff too. And, you I've done in -person stuff, hands-on work on people and their exhaled test sometimes has gone up by 15 or 20 seconds, just getting better mechanics too. So they're all tied to each other. Gotcha. All right, cool. Well, we have just a few minutes left. I had two questions to go. One was on HRV, really to kind of just parse out the difference between the RMSSD and the SDNN because of what I discussed earlier about my HRV being so apparently so much higher with Apple Watch than what most people are receiving with their RMSSD. and then kind of how that plays into breathing and recovery. And we don't need to go super down the rabbit hole here, but if you have just any kind of thoughts to distinguish between those two models and what you prefer to use. Yeah, the short version is I like using a time domain measurement. I don't use a lot of nonlinear frequency based stuff. People can look up that. A great article called Everything Hurts by James Heather that covers all that and excruciatingly detail. Most people need to double check what HRV method the watch or whatever thing they're using because everybody wants to go now to a proprietary method or a different method. And most of the time you can't compare one device to the other. Also devices that accumulate over sleep. They work, but if you've got a low resting heart rate like you do, you may not see that HRV change all that much to something called parasympathetic saturation. And then that tends to be a more lagging indicator. So somebody really wants to dial in heart rate variability and they want to use it to change daily training. I'll use like, I use the iFleet strap is what I use in the morning. Just put that on, do a measurement or some type of dedicated measurement done first thing in the morning. That's going to be a lot more representative and it's... It is still affected by sleep because sleep loss is a stressor, but it doesn't mess up the data accumulation at night. So if you had a poor night's sleep, yes, that's going to affect your stress level. But also the data you gathered now over a four hour period versus an eight hour period, it's not as stable. So one time measurement first thing in the morning is generally what I like to use. Yeah, I switched to the chest strap, the Polar chest strap with the Elite HRV app, which converts, yeah, it converts the score, the RMSSD score to a one to a hundred scale. So it kind of makes it like super obvious and apparent for you in the morning. And I've really enjoyed that. I think it's much more consistent than what I was getting with the Apple watch as well. All right, yeah. Apple Watch is the optical will also affect it. So skin pigmentation, how tight the watch is, where the watch is, does it move around at night? All that stuff can affect it. So you really have to look at the literature to see how they validated it. So the last thing, and I'm just really curious on your thoughts here, because I think this is something that I get a lot of feedback on from people across the industry is you get all these longevity experts. And I'm just going to call out Peter Attia and Indigo Sanmilaan as the main two. But they're always talking about how your quality of life is going to suffer if you cannot achieve. X VO2 max and they throw out some really crazy number like in your forties, you should have a 50 plus VO2 max. And then they're like for your zone two work, you know, a bare minimum to not have metabolic dysfunction is to be able to do your zone two work at two Watts per kilo, which I don't know too many people that I would consider healthy that are out there doing two Watts per kilo and keeping their heart rate in zone two. And so like, I don't know, it seems almost like a scare tactic in a way. And a lot of people are freaked out like, oh my God, I have metabolic dysfunction, I'm not healthy. And these crazy large numbers that are being thrown out by these guys, what do you make of that? And like, how important is it? To me, the best way I found to simplify it is like, just go off your VO2 max. Like I don't really give two hoots as much about your zone two stuff. If your VO2 max is 30, you got work to do. Now, if you look at the research, like going from absolute complete trash at like, you know, 15 to even 30, you see a massive increase, right? So the biggest change in percentage is going from absolutely horrible to like average, you know? Average to elite, do you still see a fair amount of pickup? Yeah, you do. What number should you hit? I know Andy's talked about, you know, 50, you know, milliliters per kg per minute. Probably a pretty good number. I would say is that on the higher side? Yes. But we also know it's going to decline at some point, no matter what you do. The, like you said, the zone two range for that. Most of that data, you know, from, you know, Alon's work is in elite level cyclists. So yeah, should an elite level cyclist be able to pull that off? Yeah, absolutely. Do elite level cyclists do more than two to three hours of zone two work a week? Yeah, because they're psychotic, crazy people, right? And if you don't tell them to do zone two stuff, you tell them, bro, just chill out and do a walk, they're going to get on their bike and ride around the neighborhood as fast as they can or something again, right? They're insane. So does that mean the average person needs to do two to three hours of zone two a week? Yeah, there's a time and a place for it, but I don't, as much as I love Peter Atiyah's stuff. I don't think you need to do two to three hours of zone two stuff every week for the rest of your life. I would much rather see people invest that time into, yep, a block of zone two stuff, get a good base, cool. Let's go into a block of seeing if we can increase your VO2 max, great. Okay, let's put something else on priority and let's see how we can hold our VO2 max at that level that doesn't take that much effort to hold a certain output. That's what I would rather do. Again, my big thing is looking at what is the output. And again, in what context? If someone's already lifting, they're eating relatively good, their sleep is good, they're getting their walks in, yeah, like their risk of metabolic dysfunction is incredibly rare. And I love Peter Atiyah's stuff, I think it's great, but he's also a crazy person, right? To him, like he was highly competitive in the past by his own admission, so a lot of the stuff he does is to that 90th plus percentile. And again, for him, that's great. If it's something you want to do, awesome. Is it beneficial? Yeah. But, you know, telling the average lifter that they need to do another three hours of zone two cardio for like years on end. Yeah, it's it's some benefit if you're doing it for recovery purposes. Cool. But zone two, you know, VO2 max pickups are just almost nonexistent. Again, as a good base, I've had people do zone two. Absolutely. But you're around that level of movement. I would much rather have people, you know, like you guys go ride a bike, go learn to surf, go kiteboard. At this point, even learn to play pickleball for Christ's sake. Like just put your body in a place where you're going to get movement. You're going to get increased heart rate. You're actually going to use your brain to not be a sea slug because you've got to coordinate all these moving things in space. I think we'll realize at some point there is a detriment to not moving on an indoor bike for three hours a week. And especially if you can do something else with that time, like go do some recreation. That's my bias. Yeah, no, I love that. So you would not say that mitochondrial function correlates directly with your output at zone two. Yes and no, it's so hard to say is it mitochondrial only because you've got, you know, fatigue, you can look at what fuels are using, are you primarily using fat? Are you one of these people that is super high stress? So you're just burning through carbohydrates doing zone two, which I have seen off a metabolic heart. So those are some other things I would look at. And if people really want to go to the nth degree, I don't know who I sold this from. So I would give them credit. I would much rather see an average general population lifter. do zone two stuff in three modalities. Can you do zone two on a rower? Can you do zone two running? And can you do zone two on a bike? So for myself, I can probably get by on zone two on a rower. I can definitely do it on a bike. Running, I absolutely fricking suck at. The pace I got, I can't even really run and stay on zone two if I'm perfectly honest. So that's something I would probably need to work on. I'd much rather see them movement competency in three different movements and hit zone two than I would be. You know, stay on a bike for three hours a week. Cool. Yeah, that's great. I appreciate that, Mike. That is all the time we have. You've answered all of my questions. I really, really appreciate you giving us your time. Yeah. Really appreciate it. Yeah. Can you let us know where everyone can find you, all that good stuff? And then Aaron, any thoughts to wrap up? Yeah, best place is the website, which is miketnelson .com. Most of, probably 90 % of the content I do goes out over the newsletter. So you can just go on there, sign up the newsletter, tell me you heard me on this show and I'll send you a cool free gift. But that's probably the best place. miketnelson .com and then newsletter. Awesome, wonderful. Yeah, we'll have all that stuff linked up in the show notes below. This was very, very cool episode for me to, I mean, I effectively was almost like a listener on this episode and it was pretty cool just to learn some new things. I have some thoughts swirling around in my head. It might turn into, I get like halfway through one session and I'm like, what the fuck was I thinking? I cannot do this, but we'll see. So we'll. Well, keep us updated on the podcast in future episodes, Traeger. Yeah. Yep. Thanks for joining us, Mike. Yeah, thank you guys, I appreciate it. I appreciate all the great questions, that's fine.