Q&A on Zone 2 Exercise with Peter Attia, M.D.

all right everyone so uh here to answer some questions about zone two um [Music] let's see i think what we're gonna do is start with a bunch of the questions that folks submitted over so let's start by just defining what is zone 2 exercise all right this is important to understand there are many different ways that people talk about zone 2 in fact just prior to hopping on this uh instagram thing um i was on a call with some other doctors and this question came up which says well my patients keep asking me what is zone 2 and you define it by heart rate and what does this mean and it's important to understand that the zone 2 that i'm referring to is a is a very pure definition it's a physiologic definition frankly it's a cellular definition so there are uh ways that people just say look zone two is eighty percent of your maximum heart rate or zone two is a certain percent of your maximum power output or what's what we might even call your functional threshold power i'm referring to something totally different and it is a cellular definition which is the highest level of energy you can put out while keeping lactate below 2 millibar okay that's a lot let's explain what it means so anytime you're undergoing cellular respiration your body is basically converting glucose or fatty acids into atp and that process can be done very efficiently with oxygen but as the demand for atp which is energy gets higher and higher and higher your body has to start making trade-offs and it has to start going quicker than it would like to and not just utilize the mitochondria and doing this process outside of the mitochondria and in doing so one of the byproducts of that is lactate so we use lactate as a proxy for any time your body is exceeding the capacity of the mitochondria and once you exceed about 2 millimole of lactate which is not a very high amount certainly higher than you are at rest but nowhere near what you would be exerting when you do an all-out effort you have sort of exceeded the threshold of the mitochondria to stay in an equilibrium where it can clear the amount of lactate it produces so that's how i define zone two and when i say i do i don't mean that this is my definition i'm saying that's the definition that i use personally and with my patients okay um a question that is not actually posed there but i think it's worth just before we get into how often should i do it is why does this matter um it's my belief that this is the most important place to be training your mitochondria and if we understand that mitochondrial function and the deterioration of mitochondrial function is one of the hallmarks of aging then anything we can do to delay that process and enhance mitochondrial function it's going to be a benefit okay so how often should i do it well we don't really know the answer and it probably depends in part on how fit you are coming in so if you take somebody who is relatively deconditioned um they might only be able to accommodate 30 minutes three times a week um and by the way their exertion level is going to be amazingly low so i prefer to do all of my zone 2 on a bike and the reason for that is on a bike you have watts watts are the ultimate metric of output which is not to say you can't be just as um you know precise when you're using a treadmill um but on an indoor bike trainer uh you know putting my bicycle on this thing called a wahoo kicker i get you know just perfectly precise information and i like to really think about everything in watts per kilo so how many watts am i generating divided by my mass in kilos and when you look at really really unhealthy people people who are metabolically very sick they would have a zone two threshold meaning they exceed that two millimole uh probably by the time they're at one watt per kilo of activity conversely when you look at the absolute fittest of the fit so if you look at professional cyclists who would be about as fit as any athlete could possibly be they're actually going to be closer to about 4 watts per kilo in terms of how much work their bodies can do while still keeping lactate below two millimole so personally i do about three to four hours a week of zone two and for my patients i believe that three hours should be the target understanding of course that you know most people have a job and they can't do this full-time but the reality is if you look at a professional athlete during the early season in their training they could easily be spending 20 to 24 hours a week in zone 2. next question is how long should i do it for and again this is a great question you know i've asked this question and many others that are being posed today specifically to indigo milan and if you haven't listened to that podcast i would definitely recommend it we get very deep into the weeds on this stuff um inigo believes that you know 45 minutes is probably about the minimum per session so in other words if if you were going to commit to three hours a week in 45 minute blocks you probably wouldn't want to go any shorter versus you know say doing 20-minute blocks every single day or something to that effect in my experiences it does take a while to get into that sort of steady state you know short intervals of zone 2 don't seem to produce the same effect as long intervals so again it depends on your fitness but certainly i would say you know striving to have as much time as you can is is reasonable and i generally recommend people start at 30 minutes if they're new to the activity uh 45 if they're not can i do other exercises before or after well that's really a great question and it depends a little bit on your goals so could you do strength training before and then zone two after well from a zone two perspective you could but i think actually the research would suggest that if one of your goals is hypertrophy or even strength uh you know big gains in strength it's probably counterproductive to finish an intense strength training workout and jump immediately into zone two the converse or the reverse of that is probably less of an issue personally i separate them on all but one day so there's only one day when i do zone two and strength from the same day and i separate them by several hours so there's one day a week it's a sunday for me when i'll do a zone two in the morning and a strength in the afternoon but if you're saying look peter i've only got three days when i can make it to the gym in what order should i do them i would recommend doing the zone two first and following it by the strength so that you don't eat into your strength goals does it matter if i slip into zone three four five during a 45 minute zone 2 workout great question and frankly this is why i do my zone 2 indoors you could say god it must be boring as all hell to ride your bike indoors and you know what you're absolutely right it's kind of boring to be sitting there indoors on a trainer three or four hours a week you know listening to audio books and podcasts the advantage is i have complete and total control over the wattage and if i were outside riding my bike that would not be the case in fact there is no way i could hold the wattage at an exact number riding outside even if i were on a completely flat surface it just doesn't work that way so the short answer is the more time you dip out of zone two the more counterproductive it is because by definition when you're in zone three four five you're producing far more lactate than your body can clear and therefore um you're taking the mitochondria out of that sweet spot so the goal should be to do this basically in some mechanism where you have great control over this now look back when i was riding a bike pretty seriously and i was good enough to be at perfect equilibrium and we had a spot where we trained for time trials um i was able to one day a week do a three hour ride in circles basically where i was constantly at zone two but you know i just think for many people um we want to separate sort of the outdoor harder stuff or even the more recreational stuff from this and i really think of this zone two as kind of a pill um and and uh you know i think that a bike and a and frankly a treadmill are probably the easiest ways to get it um sometimes i do it on a stair machine like one of those endless stair climber things where again i have pretty good control okay what are the benefits well we sort of already talked about this but i i think the most important benefits are are physiologic so um the more zone two you do the better you are able to do both glucose pardon me insulin sensitive and insulin independent glucose uptake so this makes for very efficient mitochondria when it comes to glucose disposal and and that's really one of the hallmarks of metabolic health so again when you go back to what i said earlier about these people that are you know have a zone two threshold that's as low as one watt per kilogram and you contrast that with people who are at the other end of that spectrum at four watts per kilo right like the fittest of the fit and the least fit when you look at the glycemic difference basically people with type 2 diabetes are going to be down at this one milligram at one watt per kilo and the people up at four watts per kilo are basically going to be the most carbohydrate sensitive people imaginable and remember every day you age you're becoming less and less insulin sensitive less and less carbohydrate sensitive or more and more carbohydrate sensitive less and less carbohydrate resistant and so we want to push the boundaries of that as much as possible i think the other benefits there's certainly some evidence that this uh increases our mitochondria's ability to combat reactive oxygen species and all sorts of other damaging processes involved in inflammation is it beneficial at any age young or old i would say emphatically the answer to that question is yes and of course a younger person is going to have more bandwidth physiologic bandwidth i mean to explore a broader array of energy zones so um you know a younger person is going to be able to make zone 2 probably a smaller part of their overall exercise program and whereas i think as we get older even certainly at my age you know it's unless interested in now how well i'm performing for any reason other than my overall health and therefore i put more of my relative exercise time into zone two um also again it's always worth reiterating this point um you know the amount of time you spend in zone 2 is heavily dependent on what your aspirations are um and what energy zones you spend any time in are going to come down to that so for example i really only spend time in two energy systems when i'm exercising so right now i'm in zone one which is to say doing nothing but i basically only exercise in zone two and zone five occasionally i go into six but i spend virtually zero time in zone three and four pretty much never um and the reason is i don't do a sport i don't you know race or do something that requires that physiologic level so i'm not really optimizing for it i'm optimizing for metabolic health at two extreme ends of the spectrum why should i do it compared to any other options for example hit or high intensity interval training well it's doing something quite different from hit in fact this is funny this came up exactly on a call that i had as i was saying and what i was saying is i think a lot of the hit literature benefits from the fact that hit is so easy to study because it's a it's a relatively easy medicine to take if you think of exercise as an intervention because you know you can say well look you're going to do a four minute tabata twice a week and we know that everybody can do that and if the control arm is doing nothing then you have a pretty good sense of what you're doing but we don't want to confuse the the promising or interesting literature on hit with the benefits that we see from a more protracted uh type of activity like this i would say that they're doing different things um which is not surprising right if anyone's ever done you know a tabata versus a steady zone too you realize they're they're as dissimilar as fasting is from eating a mediterranean diet why would we expect those things to be the exact same so i would say don't the the question why should i do this instead of hit is a false equivalency right i would say instead think why can't i do both or whether you choose to do hit or zone five which are different think of it through that lens can i use a lactate meter sparingly absolutely in fact i was just going to talk about that so this is what i use to check my lactate now if you followed me at all you know i'm a numbers guy i'm all i've got two glucose meters on i'm always doing something crazy um and i check my lactate after every single zone two ride and since i'm doing four of them a week and i've been doing them for almost three years and i write down every single day i write down this was my power this was my heart rate this was my lactate you can imagine how many of these cards i've got stored up do you need to do that of course not for one thing it's a stupidly expensive pastime i don't remember how much this thing cost but it wasn't cheap probably 250 bucks but what really gets you is these damn strips which it's they're four bucks a pop because it's like 100 bucks for 25 of these so you know i'm wasting 16 bucks a week just checking my lactate but why do i do it well i do it because i've learned so much about how understanding where my zone 2 is on any given day is a function of my power in other words how much power am i putting out on the bike my heart rate how i feel how rested i am um where i am physiologically in my stress cycle so am i over trained or under trained uh frankly even my glucose level tends to play a role and so uh just just to give you two examples um the last two workouts i did so today's and sundays had the exact same power to the watt the exact same heart rate to the lot on sunday my lactate was 2.1 at the end what does that mean that means i was actually a little bit outside of my zone too and the funny thing is in retrospect i kind of felt a little bit tired today i thought i'm going to see how i feel but i was ready to bring it down a notch and by the end of the work i was like i feel fine and i was at 1.4 millimole today and that told me hey rely a little bit more on how you feel you could have pushed the wattage a bit higher today so um if you let's so so let's put it aside for a moment if you want to use lactate monitoring you're going to get the best insight possible what if you don't either because you don't feel like wasting the money or you don't like poking your fingers or whatever then what i think you do is you start to triangulate between heart rate and perceived exertion i always think a great place to start is where phil maffetone has people start for the maf which is 80 of maximum heart rate but i want to make sure that people understand when we say maximum heart rate we mean actual maximum heart rate not predicted so if you want to know your maximum heart actually do some crunching and munching like you you gotta actually go out there and figure out what your maximum heart rate is and when you know that number um you know doing a treadmill test or some sort of exertion test uh then what you do is uh you take 80 of that and say i'm going to start there as far as exertion goes uh i would say you know i can mostly nasal breathe in zone two but frankly it's a bit uncomfortable but i certainly am not going you know the way i am when i'm doing something all out so i can mostly nasal breathe and i can talk but i just don't want to um someone asked me if i was going to do this one hour session whilst doing zone two and i actually thought about it but i was like eh it's just it's not going to be that much fun for me not that this is that much fun but anyway you know what i mean uh it would just be too much of um too much of a stress whereas you could at least entertain that idea um so what i would say in the best state is maybe periodically check your lactate like once a month once a week and learn to rely on those other signs and and things such as your heart rate and your perceived exertion um the okay so i think let's just start taking some of the live questions now i do have more questions here but let's um let's oh boy there's some really other ones okay let's just let's just see what people are asking okay um how it how is it eighty percent my garmin at zone two is sixty to seventy percent this is confusing okay so good question so heart rate monitors when they tell you their zones they might not be they're probably not referring to the zones we're talking about your garmin might be working off the seven zones that are cycling power zones the ftp zones and you're absolutely right an ftp zone two is well below a lactate zone two in fact and i'm very familiar with those seven zones because that's what we trained in cycling and i know that my cycling zone two sorry my current zone two uh would have placed me sort of low zone three on the cycling one so again what i would say is always discard the definitions of what everybody else is telling you zone two zone three it's irrelevant call this a new you know a new thing and and let's just deal with that all right i need to lose 145 pounds what do i need to do to kick my ass into gear i don't really know but i think zone 2 would definitely play a role in that do you recommend i can't read boy these are moving too quick how do you find zone 2 or watts on a treadmill great question okay it's really the same way so let's just talk about how you first make a stab at your zone 2 if you're trying to titrate that level up so on a treadmill what i recommend is not doing the flat setting and going as fast as you can go but instead using an incline and a brisk walk so um what i recommend is it depends on you know your knees and your fitness and things like that but it would be you know sort of start at six percent and three miles per hour now i wouldn't even test a level or make an assessment until i'm at least 15 minutes of steady state and then i would do if again i think at the outset you just have to accept using lactate on some level um and then i would do the check and then adjust accordingly but i would give myself a minimum of 15 minutes between making any changes i do want to make one other point that i that is worth making for anybody who's going to be using one of these devices which is unlike glucose which when you check glucose using you know a device like this with a glucose strip it's more than sufficient to just take an alcohol pad wash off your hand and poke it but lactate uh is not really something that comes off with alcohol it needs soap and water so when you're testing lactates you have to be able to wash your hands with soap and water and when i was early on um doing this testing i would actually keep a super i would keep two rags in buckets next to my bike on the stand and one was like a super soapy one and then one was just a clean one and so when i was on the bike having to test i would ride do the clean my hands it was soapy and do the whole thing and so whether you're on a bike or you're on a treadmill you're at the outset gonna probably have to do that if you're doing a graded test to find your level the other thing to note if you're not doing it on a device that for which watts is spit out is pay attention to the mets or metabolic equivalents so on a treadmill or on a stairmaster or something like that you'll often see mets spit out as the equivalent and of course there's a conversion between them but it doesn't really matter for the sake of this does your zone 2 range significantly change over time as you gain in fitness phenomenal question and exactly not only does it change over time it should be an aspiration of your fitness so when i started doing zone 2 again a few years ago i was really out of zone two shape to be completely uh honest all i had been doing was high level intensity training so i was lifting weights like crazy i was doing tons of sprinting tons of tabata tons of that and my aerobic base had withered away to nothing and when i did my first zone two test it was about 175 watts uh maybe 170 watts on a bike and i was shocked i was like that's really amazing that it could be that low given what i know it used to be and you know today it's about 215 to 220 watts so that's better and i think my aspiration is i want to be at about 240 watts by next year and again that's all based on my metrics of watts per kilo because i want to be at 3 watts per kilo which i think is you know good for an old guy who's not a professional athlete so yes we absolutely want to track this metric and i believe everybody should know their zone two in watts per kilo and should be just as concerned with that as they are with any other metric such as vo2 max or how much they can deadlift or whatever it is i just saw a question about maf using 180 minus your age and i think that is a very reasonable place to start but it is not the same and so for example if you go 180 minus my age um that puts me about eight beats per minute lower than my zone two heart rate another thing i want to point out is my zone two heart rate has also gone up over time with my zone two power so as i've gotten more efficient i can not only do more work at zone two but i can actually sustain a higher heart rate at zone two although as far as i can tell my maximum heart rate has not changed one iota in five years it's on sunday i did a max heart rate effort and it was to the beat what it was about five years ago so i don't think it's been any i don't think there's been a demonstrable change on my ceiling i just think my zone two is is is ratcheting up a little bit uh can you rent one of those lactate devices man i don't know if you can but you sure should be able to um and i don't know if that's an interesting enough business but i i would certainly lend mine to a friend if they needed it and didn't want to fork over zone 2 before or after meeting but sorry before or after eating and then the sensitivity of lactate threshold power okay great question on the eating um i have noticed that it depends on what you eat of course but if you eat something that spikes your glucose i noticed that that can have some impact on lactate but not as much as i would have guessed so keep in mind glucose is obviously an important substrate for the mitochondria and as is fatty acid um in a fasted state your body has more access to fatty acid uh than in a fed state okay so so let's just restate that so when you're fasting you're at your lowest level of insulin which means you have the maximum amount of fatty acid turnover so you your body is going to have most access to your fat stores and um of course depending on your insulin sensitivity you may have a lot or a little free fatty acid floating around and you'll obviously have some amount of glucose just because of the liver doing its thing and keeping glucose in the circulation now what you eat can also factor into that so if you eat a high fat meal you're also going to have a ton of fatty acid substrate laying around if you eat a high carb meal you're definitely going to eliminate fat because you're going to just have the glucose from the meal the glucose from your circulation and you're going to suppress the glucose of your pardon me suppress the um uh the liberation of fatty acid so i don't think i can speak to this convincingly but i would say empirically or anecdotally i think a high carb meal slightly impairs my zone two meaning i will tap out earlier because i'm forcing all the substrate it to be glucose the other question that was asked there was if i understood it correctly how does zone 2 compare to threshold power so if that's the question what that person's referring to is presumably functional threshold power so for anyone who's a cyclist they know what that means so functional threshold power is the maximum power you can sustain for one hour and for most cyclists knowing that number is super important so whether you're a climber or a time trialist or a road racer a crit rider you should know that number and most of your training is predicated on knowing that and in cycling the the andrew coggin system is based on seven zones around that number so every zone is a percent of ftp and ftp sits in about zone four upper zone four so by that metric our the zone two i'm talking about is lower zone three so if you're coming at this and you're a cyclist and you're saying what's this zone two that peter's talking about plug yourself into the bottom of your zone three and that's about where you'll be can zone 2 improve insulin independent uptake after a meal yes it most certainly does in fact i notice that after a zone 2 my carbohydrate tolerance is really at its highest um and i can you know put away a couple hundred grams of um of glucose with barely a budge on my cgn especially if it was done fasted because remember if you're doing it fasted you've got the added benefit of depleted glycogen to begin with and then you add this insulin sensitivity stimulus and so you've got and the utilization of muscle glycogen uh so you you really ramp that up uh zone two for patients taking metformin oh good i'm glad somebody brought this up okay so um in my experience both personally and with other patients uh metformin categorically lowers zone two so what we notice in patients on metformin is even fasting uh pardon me even at rest so before you do the test uh your their zone their their i'm sorry their their plasma lactate or you know capillary lactate uh can easily be close to two um and why is that well um you know metformin inhibits complex one of the mitochondria among other things metformin does so many things uh that i suspect part of what it's in it what it's doing is sort of weakly poisoning the mitochondria and so when a patient's taking metformin we tend to notice they have higher uh fasting or resting i'm sorry resting levels of lactate and their zone two thresholds are lower than when we stop them at foreman uh and i've done experiments on and off metformin and i notice a 15 to 20 watt difference uh so in other words on metformin my zone two is 20 watts lower now that's interesting but i i still don't know the answer to a question which is does that matter right so in the end we want to be very careful that we're not just in the number chasing game you know what's really interesting to me is is there a true physiologic um consequence to metformin that matters beyond what the number is and to answer this question actually uh myself and another person are going to be funding a study that looks at this in healthy volunteers so this is a study that was actually supposed to start several months ago but because of covid there's been some issues with recruiting patients in the irb and such but it's going to be a study done by inigo san milan at the university of colorado and it's going to actually take a look at non-diabetic people on and off metformin so each patient serves as their own control so it's called what we call a crossover on and off metformin and looking at mitochondrial performance using muscle biopsies so maximum zone two efficiency in that setting and and to me that's going to be the question that matters so in other words it's really going to be less about what the lactate is telling us and more about what is the true mitochondrial function at a level that only a biopsy can tell us i've noticed that my energy levels are extremely low with glps okay well that's not really what we're talking about today but yes if you're new to a glp and i assume what you mean as a glp one agonist this is that new class of drug well they're not that new but many people have probably seen the study that got a ton of news last week on a drug called ozenpic these are drugs that do amazing things for insulin sensitivity and uh and and weight loss uh not surprising that you're struggling with that a lot of it probably has to do with the rapidity with which you're losing weight so in our experience patients for about eight weeks on those medications will feel pretty crappy or can feel pretty crappy but then they tend to equilibrate um biopsy is our great future i couldn't agree more did see will this be saved to a page to view later yes i believe it will i'm going to save this and i think we're going to post it somewhere um does zone 2 increase hrv okay good question um again i haven't seen data to this effect what i can tell you anecdotally from our patients is um not that it increases hrv per se but that it increases deep sleep so a number of our patients who use tracking devices like the aura ring say um my zone 2 training has really added tons of time to my to my deep sleep you know it's gone from being an hour a night or 45 minutes a night to 90 minutes a night um so i've had enough patients say that that i i wonder if something is there it's certainly interesting um personally i have not observed that so i have not observed a change in my sleep with and without zone 2 or a change in heart rate or heart rate variability oh someone says they have a published paper um that shows zone two increases hrv so maybe on the other instagram post for this you can put a link to that um oh boy these questions why are they going so fast could you do a session on hrv yes probably going to be doing an entire ama on hrv in fact the only reason i haven't done it yet is we have so many questions that i can't get through it in one ama session our notes on hrv are about 50 pages long and i'm just trying to think how the hell can we condense this into something digestible um what is the role of zone one well interesting um i mean zone one is what we would call active recovery so let's let's let's be honest um you know as as easy as zone two is it still requires some exertion um and if you're really truly spent it's by no means a complete day off zone one is right so conversely zone one is you know basically going for a walk um you know to turn walking into zone two it needs to be very brisk or up a hill so i think it really comes down to people who are doing a high enough volume of training that they need some time at an even lower time zone for me for most of my patients that's really no longer an option or necessarily a requirement because that the amount of time i have to train is so low that i just don't you know i mean if i can train 12 to 14 hours a week i want it to be very specific and if i'm gonna take time off it's gonna be playing with my kids which maybe that's zone one but i'm certainly not gonna sit on a treadmill or a bike and go you know at 150 watts like i'm not going to do that now because i just have a better use of my time whereas i did that kind of stuff when i was spending 28 hours a week on a bike which i was at one point in my life um how do you find max heart rate with just a treadmill so what i recommend is you know it's obviously something you need to be very careful with um but you be i recommend doing uh basically running a bruce protocol uh so the bruce protocol which is named after famous dr dr bruce uh is the way we do cardiac stress tests on patients and actually it's a 21 minute protocol that is pretty much geared to take you to the max and virtually nobody can make it to minute 21. it's also not something you could do on a regular treadmill because the incline at the end is far steeper than most treadmill goes but what i basically would recommend doing is a three minute ramped effort and it's a combination of speed and grade but a greater emphasis on grade than speed which is what makes it a little bit safer so i think even in the bruce protocol you never i don't think you really ever get faster than maybe seven miles an hour but you're at 22 grade by that point this brings me to another point that i should have mentioned earlier and i bet it was asked in here and i missed it zone two tends to be activity specific so a lot of the questions our patients ask are hey peter is it cool if i go back and forth between doing my zone 2 on a bike one day on a treadmill one day on a rowing machine one day and look the answer is of course it is but you won't make progress as quickly because you're going to your body gets better at one thing so i am way better at zone 2 on a bike than i am a rowing machine so if i take my zone 2 wattage if let's just say i'm about 215 to 220 watts on a bicycle so meaning i'll sit on a bike at that wattage all day and my lactates just below two when i go to my rowing machine and do the same wattage because in a rowing machine you can control your pace perfectly and i think that would be about a 155 split for 500 meters or something to that effect but there's a converter that will tell you exactly how many watts you need to be which i've done after just 20 minutes of that my lactate's like four and a half and um i think that's just frankly because i'm not a rower and i'm not efficient at that and i bet that if all i did was row and got my lactate totally tuned there and then i went and did something different it would be the opposite and i have patients for whom on a treadmill they can do x and then you put them on a bike at a similar met and their lactate is much higher so i would just say be mindful that as you think about how to go about doing this progress on the book eta no idea hope hoping for early 2022 though um swimming for zone two that's an awesome question yeah i would bet it could be done i really would i think swimming is one of those sports where you know certainly in a pool you have absolutely enough control over your pace um that i think it would be an amazing way to get zoned too and again it's a little bit harder to sort of measure lactate in a pool but again if you started from the standpoint of okay um like i i know what my maximal heart rate is i know what my 80 of that is and especially if you're willing to just swim i don't know i'm going to jump in the water and swim 4 000 yards without stopping and know what my split is so i'll give you an example i've never thought of this before but when i was doing ultra-distance swimming like marathon swimming most of my swimming was done in the open water of course but there was one swim in particular i won't get into the reasons why i had to do all of my training in the pool and um it was a 25-yard pool on top of that so i didn't even have a long course pool so i was doing like every weekend i had to do at least one swim longer than 16 000 yards of uninterrupted swimming and at some point it was as high as 27 28 000 yards of uninterrupted swimming which as you can imagine is like unbearably painful and the only way i could keep track of how far i was swimming because i just can't count that high was i wore a watch and i would check my split every 500 yards and that meant i had to swim exactly the same pace every 500 yards and so yeah it couldn't be done i i would basically hold the exact same split for 500 yards and every 500 yards all i had to count was five hundreds so it was you know one five hundred two five hundreds and then you sort of knew how many five hundreds you'd swim and that was a lot easier than managing the yards so yep i would say something would be awesome now that i think about it so thanks for bringing that up if zone two on a rower is three watts per kilo good look i think 3 watts per kilo of zone 2 is very good regardless of what avenue you get it on so meaning if you can do 45 minutes at 3 watts per kilo of body weight you're only one watt per kilo below what a professional cyclist is doing and again we would hold them up as the absolute benchmark of the like i don't think anybody has a better mitochondria than a professional cyclist right um again we might be splitting hairs here you could argue the world's greatest marathon runner has an equally good you know kipchoge's mitochondria are just as good and by whatever metric he would be just as efficient why not go at three millimole good question um i think what you'll find is at three millimole there's no sustaining that indefinitely what happens at three millivolt is it starts to creep up and the reason is it's empirical but um at three millimole your body's ability to clear that as quickly as you're making it doesn't become sustainable um now there are probably exceptions to that rule so there are going to be people who have more transporters that can get lactate out of the cell quicker or their liver is going to be more efficient at converting lactate to glucose but but what we find in general is once you go above two and continue at that same tempo it stops being sustainable and the lactate will rise no by the way this is the other thing i should have mentioned earlier um this is not the same as lactate threshold and lactate threshold is not the same as functional threshold right so there's all these different there's nomenclature so complicated so um your lactate threshold is is something that's actually calculated off what's called the lactate performance curve where you generate lactate so you on the x-axis and the y-axis you have lactate on the x-axis you have um exertion so on a bike you would do it as watts running or swimming you would have it by pace and you plot the lactate level as these things move and the simplest way to do it is just a mathematical tangent trick where you when you see the curve there are basically the curve can be approximated by two tangents where they intersect tends to be the lactate inflection point and that tends to be the threshold and what that basically tells you is once you hit that point you're taking off really quickly so knowing that is that's about the place where you would you know that's so if you're running a marathon for example you can you can run that last half mile at about that pace but not much more once you get above lactate threshold you need to rein it back in pretty quickly and so and that's by the way that's true no matter who you are right so even the greatest cyclist in the world when they're pushing up al duez and they are at moments exceeding lactate threshold they have to rein it back in um you know they might be able to sustain that for 20 or 30 minutes but they're they're going to have to pull that back on the descent if there's another climb to be had um when do i check my lactate post workout immediately right so this is not one of those things where i uh finish the workout you know do my stretching and then check it no no it's lactate clears quickly when you're not exercising so i've got you know about a 60-second window to get that thing checked and and so i'm pretty anal about it as you can imagine i've got my i've already taken the strip out i have the little poker i have all my stuff sitting right there to do the check the second i'm done um have i used my cgm to titrate my zone two looking for optimal power pace heart rate for glucose disposal oh boy that's a great question um i'm trying to and i i i don't i haven't been able to kind of figure out what the what the formula is but i know the following when i'm doing zone two my glucose disposal follows great and if i'm fasted it's even better um but i but i don't think i have a better sense of it than that um uh is there a benefit of hot and cold water therapy at bolstering cold too that's a really good question and i don't know the answer but i have done some sauna testing to see if extreme heat can get my lactate up to two and i have not got hot enough to get there yet but i'm still trying so i do have a hypothesis that um when you look at some of the benefits of sauna and we covered this i think in one of the amas i think the benefits of sauna are legion and it certainly begs the question what mediates that benefit uh well well certainly one of the things that would be sort of you know sort of a cardiovascular component of you know extreme heat and so i was curious if being at you know super high heat in asana was generating um enough lactate and i have not found it yet so uh doesn't mean that's not the case but but i haven't seen that and someone i can see is just asking that actually is fasted cardio superior for fat loss um yeah again that's a complicated question um i i would say it depends i think that's a bit too complicated uh does zone 2 help the cns depends what you mean by the cns but probably not in the way you're asking it if you're asking it does it help your brain yes but it's not i don't think of this as a form of neuromuscular training um the way we see the higher intensity stuff or some of the strength training so do i think therefore that uh l1 sorry i don't know what that question means you can superstarch prior to zone two or fasted yeah i usually do it fasted i do my zone twos in the morning and i do it before i eat um but i i would fully endorse taking a you can before if you felt you needed to is zone two different than math yes uh discussed earlier in this video will be available for folks who understand that where did i purchase this meter i found it online again it's novo biomedical lactate plus it's a ripoff i'm warning you um latest thoughts on rapamycin loving every second of it how often do i recommend doing zone twos at least three times a week i like four does it feel unbelievably slow in zone two no not unbelievably slow uh as i said it's uh uh it's it's it's it's just on the uh just on the verge um what is the actual definition of zone two okay already covered uh won't your lactate be at the highest at the end of the ride um not really it again it depends i mean that's what we're looking for to be to be honest right so what we're looking for is being in that zone long enough that you reach a new steady state so for example if you're zone 2 if you believe it to be 175 watts and you spend 45 minutes at 175 watts and you check it every 10 minutes um if it's a if it's 2 millimole at the end you're right it was below 2 millivolt you know probably 15 minutes in you were only at 1.5 in fact i've long stopped doing that but initially i was doing that i was doing checks every 15 minutes and what you realized is you sort of get this curve that looks like this but again you know if you're in zone 2 usually about 30 to 45 minutes in it kind of stays put and it's that plateau is what you're looking for any evidence that zone 2 promotes angiogenesis of coronary collaterals not that i'm aware of what does your threshold training protocol look like over under sweet spot well again i don't do over under sweet spot anymore because i don't ride a bike any i mean i don't you know do anything serious for cycling when i do zone five now this is my workout and it's super easy peasy it's three minutes at zone two one minute at um [Music] effectively close to a vo2 max effort and the way i titrate it is it's so hard that i need the three minutes in zone two to be ready to do it again if that makes sense so again um from a heart rate perspective when i finish it when i finish that one minute i am at i'm within two beats of my maximum heart rate um but obviously just at the end because i to be able to sustain an effort for one minute remember it's a lot easier than like a 10 second all out so it's my hardest effort i can sustain for 60 seconds such that three minutes later i'm ready to do it again so that's a four minute cycle that i just do over over over over over for you know five six seven rounds and by the way i'm only doing that once a week um do i always bike for zone two these days yes i bike exclusively for zone two back when i traveled a lot if i was at a hotel or at a place where the bike sucked i would treadmill and i had a hole i knew exactly what i needed to do on a treadmill it was whatever this deepest incline is on treadmills i think it's about 15 degrees and it was i forget how many miles per hour but it was you know less than four miles per hour it was a very brisk walk at 15 degrees so and that was totally adequate um bike outsider on trainer well obviously more enjoyable outside but in on the trainer is really the easiest way to do this all right i'm gonna we're gonna go three more minutes here how does bodycomp fit into watts per kilo well i think of body comp as a different set of goals so i think it's important to have lots of different metrics and so i think that when it comes to body comp i think what we want to really focus on is what fraction of the body is lean mass and what are we doing to maintain lean mass as we age so that's something where we look at dexa scans and we think a lot about you know hey you know can you go from you know being 45 to 55 and preserve lean mass that's an important goal um with respect to body comp and then of course you know how many watts per kilo can you do and what how much can you prevent that decline uh so that you know by the time you get to the finish line can you be above a certain level um vo2 max is also something i have a point of view on right how how high a vo2 max do i want to have at the very end of the line and how do i work backwards to where it needs to be today how does glucose disposal increase longevity it is one of the most important parts of longevity and when you look at the relationship between glucose disposal and longevity this is one of the most common things that deteriorates with people as they age not even in a disease state meaning you don't have to have type 2 diabetes which is obviously a failure of glucose disposal but i'm saying even a person without diabetes is going to see a slow drift towards reduced glucose disposal um all right we've got another minute here does zone 2 increase no production um you know that's a very good question i should probably know the answer to that and i don't so hopefully someone does know the answer to that is kevin sayer trying to create yes i think dexcom is very interested in um many people having access to uh cgm it is obviously an important tool for not just diabetics but obviously everybody alright guys well thank you very much that was fun that hour floated by pretty quick and i'm gonna save this video we'll repost it probably as an ig story or on igtv so anyone who missed the beginning can hopefully check it out when it's all said and done you

Channel: Peter Attia MD

Views: 349,621

Keywords:

Id: txLrNhv8GW0

Length: 55min 48sec (3348 seconds)

Published: Wed Apr 21 2021

Reddit Comments

[u/Hjdte9yd7t]

00:00:00​ – Intro

00:00:23​ – What is Zone 2 exercise?

00:02:52​ – Why does Zone 2 exercise matter?

00:03:20​ – How often should I do Zone 2 exercise?

00:06:42​ – Can I do other exercises before or after Zone 2?

00:07:52​ – Does it matter if I slip into Zone 3, 4, or 5 during my Zone 2 workout?

00:09:48​ – What are the benefits of Zone 2 exercise?

00:11:18​ – Is Zone 2 exercise beneficial at any age, young or old?

00:12:54​ – Why should I do Zone 2 exercise compared to HIIT?

00:14:20​ – How can I use a lactate meter to measure if I’m in Zone 2?

00:16:53​ – How do I measure if I’m in Zone 2 without a lactate meter?

00:18:54​ – Peter begins to answer live questions

00:19:11​ – Why do some wearables have different definitions of zones?

00:20:22​ – How do you find Zone 2 on a treadmill?

00:21:27​ – How to use a lactate meter to test your lactate levels?

00:22:50​ – Does your Zone 2 range change over time as you change your fitness level?

00:24:31​ – How does MAF work in measuring Zone 2?

00:25:58​ – Should I do Zone 2 before or after eating?

00:28:00​ – How does Zone 2 compare to Functional Threshold Power (FTP)?

00:29:58​ – Zone 2 for patients taking metformin?

00:33:47​ – Does Zone 2 exercise increase HRV?

00:35:33​ – What is the role of Zone 1 exercise?

00:37:12​ – How do you find max heart rate on a treadmill?

00:38:31​ – Does it matter if I do Zone 2 exercise on different devices (bike, treadmill, rower)?

00:40:15​ – Can you swim for Zone 2 exercise?

00:42:24​ – In Zone 2 on a rower, is 3 watts per kg good?

00:43:10​ – Why can’t you do Zone 2 at 3 mM of lactate?

00:44:00​ – What are the differences in lactate thresholds and functional thresholds?

00:45:42​ – When do I check my lactate post-workout?

00:46:15​ – Have you used your CGM to check Zone 2?

00:46:48​ – Is there a benefit of hot and cold therapy to bolster Zone 2?

00:48:13​ – Does Zone 2 exercise help the CNS?

00:48:40​ – Can you take UCAN before Zone 2 exercise?

00:49:44​ – Will your lactate be the highest at the end of a ride?

00:50:56​ – What do you do for Zone 5?

00:53:06​ – How does body comp fit into watts per kg?

00:54:06​ – How does glucose disposal increase longevity?

[u/LuckyAwareness1982]

Love Attia's stuff and maybe this was just the wrong format, but I feel like he kind of glossed over the HIIT vs. Zone 2 comparison ("HIIT's easier to study. They're different. Why not do both?") .

I'm very far from a scientist, but it seems like a lot of the benefits of HIIT (increased VO2 max, mitochondrial biogenesis, fat loss) and LISS are pretty similar and I'm kind of struggling to understand this. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5407969/

[u/Brilliant_Cry6181]

So I've listened to Peter's podcast with Inigo San Millan twice and his Zone 2 AMA twice and I still have a fundamental question about how to train for optimal metabolic health.

As a background, I'm a male in my late 40s, cycle 4-6 hrs per week depending on time of year, variety of formats: outdoor group rides, TrainerRoad, Zwift, Peloton, occasional racing with lots of intervals/efforts in all zones. My FTP is around 300, 4.5 w/kg. Yes, I am interested in performance but ultimately optimizing metabolic health.

I understand that what Peter and ISM define as Zone 2 threshold, i.e. blood lactate 1.8 - 2 mmol is a proxy for mitochondrial efficiency, mitochondrial density, efficient fat oxidation, etc and generally overall metabolic health.

What's not clear to me is whether primarily training in zone 2 with the amount of time I commit (4-6 hrs) is the optimal way to improve my zone 2 threshold.

Based on years of accumulated personal experience, I believe that if I shifted my current training to primarily zone 2 sessions, my FTP would drop and I suspect my zone 2 threshold would also fall. This seems counter-productive to me.

My hunch is that for ISM's elite athletes who are training 20+ hrs per week, extended zone 2 is perhaps more beneficial and ultimately necessary to sustain such high levels of training.

I'm just not convinced that for a lower volume athlete such as myself, extended zone 2 training is the best way to stimulate zone 2 (and hence overall metabolic) efficiency.

Would love someone with the right background and experience to shed some insight...

[u/AdeleClimbs]

I am working my way through this. TY for sharing.

As a pelotoner, I do alot of Power Zone rides which include somewhat the cellular defintion of Zone 2 - probably very close to endurance rides.

Edit - Peter has now covered this in video - essentially saying the zone 2 he is taking about is low Zone 3 on the Functional Threshold Power test.

Very helpful.

[u/DavidNipondeCarlos]

This is similar to the 20/80 rule used by Olympic coaches starting in the 50’s. 10% is HIT.