#41 - Zone 2 training: why all the talk? With Dr Andrew Coggan

hello and welcome to inside exercise I'm emerges Professor Glenn McConnell today I'm bringing to you associate professor Andrew Coggin from Indiana University Purdue University Indianapolis IUPUI um he's an expert on um all sorts of things he's done a lot of training studies a lot of Tracer studies looking at metabolism but he's also got a very interesting background that he was an elite time trialist having won time trials in four different states in America and he also brought out a book called training and racing with power with Hunter Allen so this is where he talked about

functional threshold power and the seven different levels of training to achieve your goals um this isn't then sort of morphed into a lot of different sort of uh training Zone discussions so you know five zones seven zones eight zones and then more recently a lot of discussion about this zone two training where people feel like if you're not training at a relatively low intensity then you will not be learning how to burn fat and that will mean you'll have sub-optimal responses to training so we talk about this and as you'll see Andy is not a

big fan of this sort of uh in an obsession about about training in particular zones and we talk about how you know there's plenty of ways to skin a cat as he says or the concept of all roads lead to Rome and he says you know rather than worrying about these exact zones you're training in worry about training specificity um and what you want to gain from your training so a very interesting discussion I think you'll enjoy it and learn a lot so stick around hi Andy welcome back to inside exercise thank you very much

for coming on oh thanks Glenn I'm happy to be back I'm doing well on vacation down here in sunny Florida yes so you were saying and I thought it was very nice of you to want to come on while you're actually on vacation that you wanted to hit these deadlines and then go down to sunny Florida so did you hit the ground deadlines uh I didn't hit all the deadlines no okay so I've got uh two things I'm working on that have to be done even while I'm still here so yeah it never ends so

you'll be in trouble with the family right yeah no I warned my wife in advance that I was doing a podcast so and she was okay with it all right good so so you've already been on as I said so you're actually the first so thank you very much for being the first one to come on we had we had like zero views at that point obviously um and it's built up so that was great and you were actually almost The Unofficial Advisory Board as well because you've ever giving me a lot of tips and

we're running ideas past so we go back a long way I Met You in 1991 I think it was uh when you were down you came down and you popped into my car garage lab my husband right yeah a self-financed sabbatical is how I described it um so so you've got a very strong background for people that don't know you've got a very strong background for many many years looking at all sorts of things the training studies Tracer studies actual guy for a while there you were like my go-to guy to ask straight questions about

traces and things and now you've been after me nagging you substantially you've been happy enough to come on to talk about Zone to you know training at different zones and all these sort of ideas about uh if you if you don't train that exact Zone the world might come to an end um you were not that Keen to come on because that is not your scientific background but uh the fact that you've written a book on this stuff and you're like the first to start thinking about training with power um I think it's great to

have you on yeah I consider that I am not you know I am not a sports scientist I'm not an applied Sports scientist I'm an exercise physiologist like you uh however as a cyclist myself and a numbers guy when power meters became affordable uh and really started to catch on you know just before the turn of the century I got sucked into that rabbit hole and since I'm a person with a lot of opinions I started sharing them online and the next thing you know I'm you know doing lectures for USA cycling and then Hunter

Allen is you know uh bending my arm and we end up writing a book and you know it all just snowballed from there but I really I always consider that Hobby you know avocation not vocation it was a side light uh so so you touched on it there and I should say when you came down to downtown bike ride and um I knew you were already strong but um I didn't expect you just to take ride away I was like piss me off actually yeah exactly right so why don't you give us a bit of

an idea and it also tracks your scientific um Journey as well that you were started off in Indiana you were like Indiana time travel take us through that no modesty yeah I started I started right I grew up in Indiana I started riding a bike when I was 14 racing when I was a 15 when I was 15. uh you know that was my identity uh that got me interested in exercise physiology while I was still a junior in high school so Ball State was just down the road so I did my undergraduate and my

Master's there with Dave costell uh my first exposure to power Based training was actually when I was an undergraduate costell wrote me a winter training program on the ergometer you know three days a week but all of the uh yeah I was doing intervals that had wattage targets right it wasn't heart rate Based training or anything like that it was you know do this interval at this duration at this power output and then try and push it up from there so but then uh yeah I I always consider myself the cycling equivalent of the of

like a 218 marathoner I was I was good enough to dream right not not good enough to make a living at it um yeah but good enough to Dream well you some of your dreams came true though isn't it correct that you were time travel champion in Indiana and then you went to to Missouri Champion there and I was part way through my Master's Degree when I committed myself to science rather than cycling and I made cycling a hobby but I'm a lifer exerciser and you like to stay fit so everywhere I went I would

try and find you know some competitive outlet and since I'm skewed Wells to the slow twitch end of the spectrum I was always good at time trials and I like the technical aspects the aerodynamics so yeah I made it a goal and so I won time trial in Indiana and then uh let's see moved to Texas and uh you know on a time trial Championship down there and then moved to Maryland then Ohio and Missouri and it's like every state I would be at I would try and take out the TT Championship um best we

ever did we actually won the uh Masters National time trial on a tandem in our our 90 plus age group as a masters and then we went out to New Mexico and set it's been since been broken but we set the uh the U.S uh tandem time trial record for our age group so nothing like motoring along at a 10 on a tandem at 32 miles an hour John John Variel he's a environmental attorney out there now but uh he was a cycling coach before he uh went back to law school I just remember while

you were talking about that sorry that that that you were barred into that with the aerodynamics and you had that hooker Elite why don't you explain that that that that was I'd never see anything like that but yeah they were a company uh actually uh hooker Industries Hooker Headers there's a couple of guys in California who are very much into auto racing drag racing modifying cars and then they got sucked into the triathlon explosion Etc and started doing that and they decided to apply their technical expertise and their ability with Metallurgy and develop a bike

brand so they were one of the very first uh you know full Arrow uh efforts out there and uh it was pretty extreme and radical for the time and of course things have moved on quite a bit since then but uh yeah so you had no there's no no handlebars right Barrel or die yeah it was it was Arrow or die no no outboard position whatsoever right handlebars were like this wide at the wide I'm sorry about the people I think 15 centimeters maybe six inches wide yeah so you just set your arms forward and

that was it and I remember you telling me to get arrow and you were like just push note down and you're pushing me pushing my back down I just couldn't I couldn't do it because because he would just train right at that when you were leading up to time trial you would just train in that position the whole time yeah yeah well and I also you know I grew up in in Northern Indiana where it's pretty flat and kind of windy and empty Farm roads I got quite used to just hunkering down and riding with

my head down so from a young age so there are actually data out there showing that in speed skaters for example the uh the thigh the hip joint angle Force relationship is skewed to a more acute angle in speed skaters than it is in untrained individuals so I think you know if you if you're doing that from a young age you develop a little bit differently and then you can picture somebody who like yourself who is a runner first right an upright posture and then in you know full adulthood you try to become a cyclist

you may be at a disadvantage to somebody who's been doing it since they were 14 or 15. I just couldn't put a life of me so you had your you had your hips I mean I know you know this stuff now but back then I was just like what the hell your hips were above your I had a lot of good input from uh various people John Cobb Jim Martin Etc and you were mucking around in um in um tunnels um era yeah I got I got into the wind tunnel for the very first time

and I don't know what year that was um but again that was courtesy of uh connected with Jim um then I eventually built built my own wind tunnel in my basement that's right it's not a big win tunnel but I did build one all right so so if we we're going to lead towards uh focusing around this zone two concept which um to be honest I hadn't heard all that much about until you know I started on Twitter I'd heard about it but and then you know with Twitter with this this podcast and uh just

keeps coming up all over the place in the zone two in zone 2A and Zone 2B and and various ideas about it zones do you want to just talk about how we how people sort of got into these zones and indeed your own um you know zones that you had with your functional threshold power Etc yes uh I don't know who the first person who would have been who would propose training zones uh or even when it might have been but certainly as a a young young and growing up I think I was exposed to

the notion of heart rate Based training zones then when power meters started to catch on it was actually a chance conversation with John varghiel in the infield at Trexler Town at the velodrome there he was part of a coaching company at the time that had their own heart rate Based training zones and he saw realized that power was taking off and he was telling the person he was talking to they're talking about Watts Etc and he was telling this person that he was talking to that he wanted to be the you know be the first

to translate their heart rate based zones to to power-based zones so it was about a two-hour drive home from T-Town to where I was living in Maryland at the time and I left the velodrome and I'm driving home and I'm thinking as I go well there's really a power vacuum here you know pardon the pun but you know SRM had been available to the Greg Le Mans of the world the Australian Institute of sport for maybe you know eight years or so but at that level people are not in the business of sharing all of

their hard-won knowledge they're trying to you know win medals and make money and keep all of their secrets to themselves so there wasn't a lot of information out there and I'm driving home and of course I have an ego as big as the uh um golf here that I'm sitting right next to and said to myself it's like well you know somebody needs to step up and you know fill this void and I felt like I was the perfect person because of my background in exercise physiology and the fact that I had gotten uh early

exposure you know I jumped on the power bandwagon so I started out by developing uh my seven training levels and uh Power Based training levels but the on the wattage list when I used to participate we would have what we referred to as pithy power proverbs short little phrases that summarized concept you get tired of trying to explain it over and over again so you end up with a shorthand notation okay and the the relevant 50 power proverb here is uh they're called levels and not zones for a reason and that is when people are

training on the basis of heart rate and heart rate basis and they have this notion that well if I'm doing a Zone x workout then I just you know modulate my exercise intensity to keep my heart rate within that range at all times and the problem is when you apply that to power on a bicycle your power when cycling Outdoors is highly variable I mean people know this but they're still surprised when they get a power meter but if you think about it when you're pedaling your power is something and then you Coast as you

go around the corner and your power is zero and then you stand up to accelerate again and now you get a spike in power so if you then apply a a typical Zone sort of perspective and you try and constrain your power output to keep it always in the same range you become a diesel engine you become a lorry right it's not The Way We Ride bicycles and it's counter productive to the overall effects of training because you need to be able to change speed right take a take a triathlete throw them into a mass

start bike race and they get eaten alive right because they're not used to changing it yeah so providing like a time trial that way yeah so one of the things I did is I borrowed the word levels from uh Chris boardman's coach Peter Keane had his own system right which he referred to different levels and I thought well levels at least hopefully will make people think differently than Zone um and then it all sort of snowballed from there you know USA cycling caught wind asked me to give talks Hunter Allen sucked me in we end

up with three editions of our book now 100 000 plus copies sold eight different languages made a lot of other people's careers um for what for me was really just a hobby is it in Slovenian maybe that's the problem yeah well glitch and Bogota Slovenian person said yeah yeah all right we might head yeah okay um all right so there's going to be controversies along the way and one I just thought of is um I mean it might be a bit of a tangent which is what you said you said we should have a bit

of a script because we tend to go off on tangents but um what was the deal with your uh there's a suffer score yeah and then there's your fdp and there was a bit of a bit of a controversy at trainer Road or something about whether you should use suffer score instead of fdp or if I got that wrong well uh the starting point was the training levels but the endurance exercise performance the single most important physiologically determined of endurance exercise performance is here what I call your muscular metabolic Fitness uh as as a Counterpoint

to cardiovascular fitness describing VO2 max and our our lab-based measurement the the standard lab-based measurement of muscular metabolic Fitness is lactate threshold now there are at least 27 different quantitative definitions of lactate threshold out there in the scientific literature right uh and but as a concept uh it also it can also be just viewed as a concept right and the fact that it's a well-established concept is probably why we don't why there are 27 different definitions in that if you go to a meeting and you say yeah you know we were testing this cyclist and

this is their lactate threshold was really close to their VO2 max right you know what I'm talking about you don't have to know which definition I was using right and if you got really curious and you wanted to say well how close you know oh it was at 98 well how are you measuring lactate threshold uh we use you know we use the one millimolar increase above exercise Baseline it's like oh okay go on right exactly so as I describe it there isn't any evolutionary pressure in the field to achieve any kind of standardization because

there really isn't a need from a conceptual point of view right we can still communicate with each other um so you know with that in mind knowing that your metabolic responses are the most important determinative performance and I grew up as the concept of lactate threshold was developing right and displacing VO2 max is to be all and end-all and even as a grad student okay now what 40 years ago I I was saying you know the best predictor of performance is performance itself yeah right it always will be right there's a perfect correlation um there

are physiological descriptors of it but uh you don't want the the tail wagging the dog performance trumps all right so now we have power meters on bikes we have the ability to measure someone's performance ability in terms of their power output we know that their muscular metabolic Fitness uh connects to you know predicts performance across a very broad range of durations right so the logical Anchor Point is a power output that is a surrogate for the lactate threshold concept right yeah well the other the other issue is you know and coaches and athletes are so

confused because if you use some of the definitions of lactate threshold you know the first apparent increase you know above resting or something like that it's a far lower exercise intensity than what athletes and coaches perceive to be threshold and that creates confusion what you're telling me my threshold is this I know it's this right so that's the thing so can I just say so so for example as you said there's all these different definitions from necktie threshold so so you know the classic one is is you know you just so people are on the

same page so you lactate you know people might think oh there's no lactate sitting here at rest but your lactate level is about one millimoles so at rest then you start exercise but it's still low intensity and it stays about one and it doesn't really change so so people might think oh nothing's happened but in fact you're producing lactate at a higher rate but you're clearing it at the same rate so it's not accumulating and then it starts to accumulate right and then some people okay that's like that threshold one other people say no no

let's not worry about that just wait until it's one millimo above that resting level but as you're saying you could do like a one-hour time trial and sit at five or six millimoles or seven or eight actually exactly connected to that and for the edification of your audience you know to me if people think about it why is the onset of blood lactate accumulation defined as four millivolar I mean if resting is one you're saying well wait a minute you've already accumulated a whole lot so why do we call that the onset so I think

the the to understand that you have to learn to think in multiple Dimensions because not only do we have to think about intensity but we also have to think about duration so obla four millimolar is the average lactate concentration across uh various you know Runners swimmers rowers cyclists corresponding to maximal lactate steady state so if you are well below you know if you're if it's a very low intensity you may not see any accumulation of lactate at all if it's a slightly higher intensity or lactate levels may go up initially but then after 20 30

minutes they go back down towards resting necklace if you go a little bit harder they go up and they'll Plateau if you go a little bit harder still they'll go up and they'll Plateau if you go a little bit harder still they increase continuously so so that happens on average at about a four millimole level but it seems to be dependent upon the amount of muscle mass the mode of exercise so for cyclists at least train cyclists quite typically maximal lactate steady state corresponds to a blood lactate concentration of maybe seven millimolar so yeah back

to the 4K 40 kilometer TT you know your average strain well-trained cyclist is probably just sitting there at seven millimolar for the duration of the event so what do they do with that so you know if they had a lactate thresh if that if that actually gone in and paid to have a lactate threshold test done what do they do with that my feeling was always that I'm throwing up my hands here like I don't know I mean it's a one-off test um you know it would tell you uh what your physiological state is at

the you know the day you took the test but uh unless you go back repeatedly it's not really useful for tracking improvements the other thing is that it's far more variable than what people realize uh you know we can reproduce performance you know plus or minus two percent in a laboratory setting in the field because it's not a controlled laboratory setting maybe plus or minus five percent right um but then when you talk about measurement of you know some lactate threshold of surrogate right the coefficient of variation is is quite a bit larger the test

retest reproducibility isn't that great because lactate depends upon how much glycogen you have stored in your muscles Etc so again people have it they think that lab-based testing is the gold standard and everything else is a poor man substitute and they have it backwards the best predictor of performance and performance itself and you know lab-based testing is the poor man substitute or it is the uh it may help you understand things mechanistically if you're a scientist but it's not the gold standard and this is one thing that I do uh would say that I agree

with in the perspective that Andy Jones is and David Poole have tried to put out there in pushing uh critical power as the new gold standard and that they are also you know of the opinion that performance trumps all um okay so why don't you um we're heading we're sort of heading towards zone two but we need this sort of background seeing as you've mentioned critical power why don't you just explain what what that is and for our listeners uh critical power was first developed by monard at all in the 1950s a mathematical model to

describe performance over varying durations uh with small muscle mass exercise let's say repeated knee extension for example uh conceptually you have a critical power that can be maintained indefinitely infinitively forever right and above that you have a limited amount of work that you can do so if you are at or below your critical power you should never fatigue and then if you're above your critical power how quickly you would fatigue would depend upon the magnitude of your originally it was referred to as anaerobic work capacity now the realization is that it's uh for last couple

decades is it's not entirely anaerobic so now it is W Prime W for work so you have a certain non-sustainable reserve and the higher you are above critical power the more quickly you will deplete it the less you're above your critical power the longer it will last but eventually you will deplete it and have to slow down to critical power so that's the concept proposed again in 56 or so it took until 1979 until DeVries and moratani extended it to whole body exercise using cycling and there are various mathematical permutations on this you know you

can either plot work against time or uh you know 1 over power versus time Etc different manipulations but it comes down to a two parameter model of the exercise intensity duration relationship it started out again primarily as a mathematical descriptor and then people began to develop more and more physiological basis for it or impetus for us impetus for it um and I'm going to let you get a word in edgewise here because otherwise I'll just go off in a real long time that's good I'm just I guess I'm wondering what do you actually do do

with that so um well you know it's it's it all models are wrong but some are useful right mathematical models often are better at uh generating new questions and they are actually answering current questions but one example of it you can instead of using power you can use paste and so you can talk talk about your critical pace and your uh your D prime your distance Prime so for my son who's a swimmer I use his uh his 100 200 and 500 yard distances and I use a linear variation of the critical Pace model and

so I track improvements in his critical swimming speed and critical distance uh you know as he develops etc etc now given that you know performance is the best predictor of performance is performance itself if you want to have a zone system and I'll come back to that in just a second uh The Logical Anchor Point is performance not maximal heart rate not VO2 max even though historically in exercise physiology we describe exercise intensity as a percentage of VO2 max that's really only the best approach if you're talking about cardiovascular responses because it's a measure of

cardiovascular fitness more generally anchoring things on quote unquote lactate threshold muscular metabolic Fitness makes a lot more sense so you could build an entire uh you know Zone based system around critical power and but obviously we're getting you know off in the weeds here talking about mathematics right and all this kind of stuff and power meters for cyclists are just becoming available and the problem is people are really confused because they think they all want to be scientists right so my attempt to kind of cut through all of the confusion was just to wipe the

Slate clean and say forget about the physiology you don't need to understand the physiology but you know that there's a certain intensity that you can sustain right I can hold this and if I ask you to go a little bit harder you're going to very quickly realize I can't keep this up right functionally speaking there is a quote-unquote threshold power right it's not a true threshold because all exercise responses reside on a Continuum including lactate and ventilation so to refer to things as a threshold is a is a mental convenience we simplify everything down and

we draw a hard Line in the Sand and we call it you know black and white you're above your threshold you below your threshold when in reality it's a curvilinear relationship with uh you know a narrow Bend in it but it's clearly still bending even in that range but nonetheless let's forget about lactate forget about everything you know let's just talk about functionally speaking you have a threshold power and this can become a good Anchor Point for well how do we communicate people I told my athlete to go easy they have a power meter well

how easy is easy right that's that's how the original training levels were born um and I think the entire purpose of training levels or zones or whatever it's really just a language to Aid in communication you know there's nothing magic that occurs about training at a particular uh intensity that wouldn't occur if you went just a little bit harder or just a little bit easier because it's all a continuum but if you need to you know I'm a graphic person I can sit here and draw lines and graphs and you know all day long but

if you're trying to communicate with somebody in language you need some kind of systematic approach and that was the the basis the original training levels yes now with uh when I first started hearing about zone two and tried to work out what it was I actually thought it was it was talking about your second level but it's but it's not so why don't we talk about what zone two is and how there's a bit of a prevailing view that you if you want to increase your fat oxidation and Etc you need to sit in zone

two and uh try not to deviate and then maybe some of the physiology behind that um yeah probably at least some of the confusion that's out there is due to the fact that there are multiple systems um at the simplest you have uh the Norwegian approach I guess you say Norwegian that Siler always Embraces where you really only have different three different ranges right um in which case you know it's one two and three and so two is the middle one um uh when I was developing my training levels and trying to think about well

how do cyclists train in order to prepare for competition I decided that seven was the magic number the set that seven was sufficient to cover all the bases and uh you know I couldn't get by with one less and I didn't want to go with one more because it made it unnecessarily complicated if you're going on heart rate well you know any heart rate based system is capped at maximal heart rate so oh yeah it doesn't really apply to you know super maximal above VO2 max efforts so the most common heart rate based system probably

Joe friel's I guess has five right all right so okay you know one two three four five or one two three or one two three four five six seven but all of these twos don't know necessarily perfectly aligned no um you know it's uh in the history of training for Endurance Sports uh I say zapotec you said zapatec uh is that a pig I thought it was emails you're the runner so yes you're the runner we'll go with your pronunciation um you know credited with inventing interval training and then the the whole no pain no

gain era to follow it was a reaction to that where Joe Henderson published his popular book on uh long slow distance training the humane way to train no more you know torturing yourself day in and day out with vomit inducing intervals you can go out and just run at a steady Pace Etc so he really popularized it even though you would say that uh uh from New Zealand who's the uh lizard a little Lydia certainly had people doing you know plenty of endurance-based training um so it would be you know zone two is long slow

distance it's all day Pace it's you know it's a comfortable Pace it's uh you know we all know when we see it right but in each different system it's there may be overlap but they don't necessarily overlap perfectly and then people want to try and tie it to some physiological marker which doesn't make a lot of sense because most people don't have access to the physiological measurements it doesn't make a lot of sense because it's all a Continuum anyway it doesn't make a lot of sense because the best predictor of performance is performance itself it

doesn't make a lot of sense because you know performance is a function of your muscular metabolic Fitness which is the most important determinative performance over a very broad range of intensities so you know why are you trying to tie it to you know LT1 right as if LT1 is different from lt2 they're not you know um actually sorry just explained that to people what you're talking about with LT1 and lt2 and why you're saying that they're not different well okay lactate threshold LT if you're plotting lactate as a function of exercise intensity let's say during

an incremental exercise test uh now the absolute lactate levels are going to dependent upon yeah your current glycogen stores your uh you know the length of the stage increment uh whether you're measuring lactate and venous blood arterialized blood arterial blood whether you're talking about whole blood lactate uh or plasma lactate and maybe even if you're doing you know capillary blood it may differ depending on whether you're getting an ear prick or a finger prick how much you squeeze it as well yeah yeah or how much sweat gets in it or the particular brand of handheld

analyzer you own you know there's a million sources of variability but at the end of the day as you were pointing out previously initially there are minimal changes in lactate and then they begin to increase more rapidly thereafter so people like to look at that and say okay here's the first uptick in some subjective manner we'll call that LT1 and then we know that there is a maximal lactate steady state it's hard to determine from an incremental exercise test but somewhere out there is an lt2 right the onset of continual blood lactate accumulation the problem

with all of this is that it's really a continuum and if you threw an exponential curve on there that would fit better than any kind of piecewise linear regression right there are no actual break points and as a consequence like a you know Ira Jacobs demonstrated a single blood lactate measurement if it you know at the right intensity it's a 200 watts is as predictive as doing you know a full curve okay you just need to know one lactate value right because it tells you where the curve is positioned and is all a continuum um

just when you said LT1 and lt2 aren't different I just didn't want people to think they were the same exact lactate measurements yeah you're just saying they're they're just a Continuum you might as well just do one they're a distinction without a difference right and remember how people used to I don't know if they still do but I tried to do it once in a while and uh you know they tried to say okay when the lactate does this the ventilation does that and then you now you try and draw the the lactate break points

against the ventilation break points you do that in tracks and things and it's hard to it's a bit of a yeah and then you can dissociate ventilatory threshold from lactate threshold by you know mcardle's disease to Classic uh like pedaling really fast by pedaling really slow by having really high glycogen by having really low glycogen if you do interval training it tends to increase your ventilatory threshold more than your lactate threshold if you do continuous training it tends to increase your lactate threshold more than your ventilatory threshold so we have lots of evidence out there

that they aren't cause and effect even though they may uh in you know terms of human physiology yeah they tend to be closely associated uh they're clearly not cause and effect sorry carlman Wasserman so so the so with the zone two yeah now why don't we talk about why are people so so I started talking about on Twitter you know Twitter it's just zone two zone two and I even gave it I gave a talk on a couple of podcasts and then you know as I do on Twitter I ask people with these questions and

there's a question like I was going to talk about you know carbohydrate metabolism during exercise and one of the questions is oh you know ask them about zone two you know just everything's zone two why don't you give us a background on you know how people uh why they're so keen on this so zone two um so you know in terms of fat oxidation lactate all that stuff there's there's been a you know a long-standing misconception that you need to oxidize fat in order to become better at oxidizing fat uh in reality your muscles are

quite good at oxidizing fat even in the untrained State at rest for example muscle relies almost entirely on fatty acid oxidation to provide its rather low energy needs but if carbohydrate availability is restricted you can exercise all the way up to you know 70 percent of VO2 max to use my classic exercise physiologist Anchor Point VO2 max with an R A 0.7 it's not necessarily pleasant but you can provide the energy that said you know since uh holiday's work in the late 1960s it's been known that endurance exercise training increases the capacity of muscle to

oxidize fat as a fuel source but you don't have to oxidize fat to actually induce those adaptations they're primarily the result of an increase in you know mitochondrial respiratory capacity where the two primary drivers are the energetic state of the muscle you know during exercise training and calcium release and it's these factors are what you know cause you to produce more mitochondria which then results in an increase in Ox fat oxidation capacity you don't actually have to oxidize fat to get better at oxidizing fat yet people have long thought that you need to yeah so

just to make sure because you mentioned there are 0.7 to make sure people are clear on this so the idea is that you know we know that when you're exercising in a low so as you said sitting at rest unless you've just had a high carbohydrate meal but something at rest if you're fasted you're burning mainly fat you start exercising on low intensity you're burning manually fat as it gets harder and harder you burn more so it would often yeah the study is rummage Etc Van Loon you know and earlier stuff 65 in a trained

person of VO2 max is about where you're 50 50 and then when it you go harder it becomes more carbohydrate so the idea there is is when your respiratory exchange ratio is 0.7 you're burning 100 fat essentially when it's one you're burning 100 carbohydrate so you're saying if you're on a high fat low carbohydrate diet you can exercise maybe at 70 and be burning almost entirely fat but the idea there is that that people are thinking okay I want to get better at burning fat so I can spare my muscle glycogen I can do better

in exercising but that's a valid thought yes but but then the question is how do you do that and the way you do this you do not need to burn fat to learn how to burn fat more you just want to increase your mitochondrial volume and you can do that by various means oh yeah many means um if you look at the animal literature these are not new questions obviously uh but if you go back to the animal literature so again Dudley 1984 uh some of the work got a policies lab in the mid late

mid to late 70s you know training rats at different intensities different durations Etc uh it seems that you know muscle respiratory capacity increases with increasing intensity of training in part because you're recruiting more and more motor units right it increases with increasing duration of daily training up to about two hours a day and then beyond that in a rat it doesn't seem like you can necessarily induce you know markedly greater improvements now stimulate the muscle eight hours a day or 24 hours a day and you may get some further increase but there clearly is a

a big bang for the buck uh you know when you first start working the muscle um and then eventually you know a tendency to sort of saturate the system so then you know that leads into all kinds of practical questions about well what's the best training program uh and then it devolves off into well what are you training for who are you how much time do you have available how much motivation do you have Etc um and ultimately at the level of the individual science can't really answer those questions right you see people posting on

a forum hey I'm you know so many years old I've been training this way for a few months my FTP is up to this what are the odds I can get it up to five watts per kilogram it's like well there's only one way to find out is it Yoda right it's like uh do or do not there is no try right all right so so basically there's a couple of things talking about there but but we know that there's different ways of increasing your fat oxidation you don't have to exercise at low intensity burning

fat to get there so classic stuff you know the high the whole hit stuff the you know the high intensity element training there's there's lots of evidence that you get essentially the same increases and and video to Max you get same increases in your mitochondrial enzymes Etc so that's showing very clearly and you're saying even if you don't burn much fat at all just say you're doing intervals twice a day every day if you get an increase in mitochondrial volume so you get the increases in Ox in you know the oxidative enzymes the fat enzymes

then you'll burn more fat during the exercise correct yes all right now what about this thing though that people are worried about ah but when I'm exercising if I go too hard I'll get lactate and that's going to inhibit myelopolysis so for a start I guess you're saying well who cares anyway because you don't have to be burning fat during exercise but do you want to just talk around that yeah so so the the misconception that uh you need to oxidize fat in order to get better at burning fat has been around for a long

time the the current uh myth that oh you know if I go too hard early in a workout it takes a long time to reset my metabolism seems to be coming entirely from San Milan and his recent podcasts um and I think people are paying attention because of who he coaches I can't pronounce his name good job okay uh but the idea that lactate inhibits lipolysis which I believe is what San Milan is uh arresting his uh belief system on actually goes back to hypothesis from the 1960s where uh Bella isakates and I don't remember

his wife's name but izakits and izakits so this was in the the Heyday of carbon 14 based metabolic tracers and izika studied exercising dogs with uh you know 14c labeled glucose 14 soluble fatty acids etc etc it is true that if you go you know hard during exercise and your lactate levels are elevated your fatty acid levels will be suppressed and uh isakates and izakits hypothesized that lactate inhibits lipolysis what we know now and what we've known since you know as long as I've been in the field right uh is that that hypothesis is incorrect

the the real explanation for why fatty acids are suppressed during high intensity exercise is that they require blood flow and albumin delivery to adipose tissue to remove the fatty acids or to Liber say release the fatty acids because fatty acids are not water soluble and the albumin in your plasma is basically the shuttle bus so during high intensity exercise when you redistribute more of the blood flow away from adipose tissue you may have a high rate of sympathetically mediated fat breakdown I.E lipolysis but the fatty acids can't escape from the adipocytes then when you stop

exercise or lower the intensity and you know you get more blood flow into the adipose tissue fatty acids will actually rebound so they can show a big overshoot post exercise uh you know how long does all of this take I you know and what effect that has time wise on muscle metabolism uh you know it's something that's difficult to study absolutely because some of our tools like indirect calorimetry require a steady state and so if you were cycling if you were fluctuating power every 30 seconds without indirect calorimetry is not a tool that would really

be helpful there but for my dissertation one of the projects we had cyclists who were drilling it at time trial pays for 15 minutes and then they went at you know easy pays for 15 minutes and then they altered alternated that as long as they could and you see this little you know seesaw action in terms of fatty acid levels in terms of glycerol levels Etc every 15 minutes where fatty acids go down during the intense exercise and then up during the easier exercise and then back down again and in that case we were using

respiratory exchange ratio over the last five minutes of each 15 minute block and if you look at the metabolic uh rates of substrate oxidation plasma concentrations of substrates Etc uh during the moderate intensity blocks they look pretty much the same as if the high intensity blocks never took place uh so so that says You must reset within 10 minutes reset right quote unquote um you think about uh elevation of plasma catecholamines well plasma catecholamines have a very short half-life you know you go really hard at the uh in an attack during a race and your

catecholamines go really high and then the break is caught and you tuck back into the field and draft for a minute or two they're right back where they were because they're cleared so rapidly so this whole notion that you know it takes a prolonged period of time to reset metabolism has no physiological basis whatsoever in addition to the fact that you don't you know who cares because you don't have to burn fat in order to get better at burning fat um right there was this concept I guess that you know the ultimate killer here I

can't resist this the ultimate killer right uh George Brooks's lab did interesting study where they did a lactate clamp so they infused unlabeled lactate to elevate lactate levels and then they also uh since lactate is a base if you just Infuse like sodium lactate you'll become alkalotic they also infused enough acid in order to maintain pH right so at a moderate intensity they could increase lactate concentrations as if you were exercising at a higher intensity and then hold them there a lactate quote-unquote clamp much like the classic glucose clamp and they were using stable isotope

tracers to measure substrate kinetics including the rate of appearance of glycerol which is produced as a result of the breakdown of triglycerides in adipose tissue and muscle is considered the best measure of the rate of lipolysis and when they elevated lactate concentrations there was no significant difference in the rate of appearance of glycerol in fact it actually tended to be higher in the lactic clamp study well okay whereas if lactase suppress lipolysis it should have diminished the rate of appearance and I only bring this up because you know the grand irony here is that San

Milan uh is seems to be you know uh heavily influenced by George Brooks but not in that regard apparently not so okay yeah all right well I think I don't fall punches as you said earlier right okay I I think that pretty much covers that but if Sam Milan was here how would he respond to that do you think well and again I you know I don't want to point the finger too hard because in quite on you know quite honestly I can't stand listening to podcasts um so I hey hang on don't turn people

off listening to podcasts I don't even listen to my own on this one um uh people talk too slowly for me I'd rather read it draw a graph give me you know give me words um if it's how to repair my dryer I'll watch the video but I'll just cut that out I'm gonna I'll modify it aside everyone listen to the podcast the only podcast I listen to is inside exercise um uh so I'm I'm uh I'm basing this more on uh what I'm reading on various web fora Etc um so it's possible that uh

his message is getting distorted a little bit before it gets to me that's quite possible hey I thought earlier when you're talking about heart rate um so you know back when people were you know before people think about lactate thresholds and uh Power zones and things exercising on heart rate and that's another one that that you get cardiovascular drift right so if you because I've had I've heard people quite often say I'm going to run this um you know I'm going to run 140 beats today I said you know but if you're doing like a

two-hour run or something you're gonna have to slow down you know like because you get this cardiovascular drift do you have any thoughts on that because I know you said we just cooked yeah we had one of the pithy power Proverbs was cardiac drift as a fact of life right yeah I mean you know they're you're never going to have a perfectly constant heart rate that your heart muscle itself will fatigue during prolonged you know moderate intensity exercise uh it's the the reddest of the red the slowest of the slow the most fatigue resistant muscle

uh but it it may exhibit some evidence of diminished function as a result of prolonged intense exercise I.E cardiac fatigue and how well your heart functions is also heavily dependent upon the environment in which it's operating filling pressures Etc so as you warm up and you have to vasodilate your skin to cool yourself you may have diminished you know Central cardiovascular uh pressure which will reduce stroke volume you're no longer stretching the heart you can't take advantage of the Frank Starling mechanism as well yet you need to maintain cardiac output to provide the oxygen to

the exercising muscles and now you have to send more blood out to profuse skin and if stroke volume is going down the only thing you can do is increase heart rate you know just pump faster right so you know even in a laboratory based setting where you are in a uh well below any kind of uh major disruption to metabolic homeostasis well below you know quote unquote lactate threshold critical power maximal metabolic steady state functional threshold power that yeah whatever you want to call it you know you'll see some upward drift in heart rate even

just core temperature increasing over time causing you know AV node to depolarize more rapidly more readily so cardiac decoupling of Life what's this aerobic decoupling uh it's cardiac drift yeah so that's just cardiac drift that's just cardiac drift what's this aerobic decoupling business well it's uh I think Joe Friel is the one who came up with that term um you know a perfectly coupled mitochondria mitochondrion there's not really a single one but a perfectly coupled mitochondrion uh the in theory the the pita o ratio should be you know three we get three ATP produced for

every uh one half of an O2 utilized right mitochondria you know even in a healthy person are not perfectly coupled um but they can become less well-coupled they can become uncoupled it could be due to mitochondrial diseases it could be due to uncoupling proteins that are expressed within the muscle uh it can be due to chemicals drugs known as a mitochondrial and coupler so people would you know in Indiana they'd uh you know poison a pond with throat known and all the dead fish would float to the surface you know I thought it was a

cool thing to do um okay I thought it was weird enough how they painted the river green so when you know because I went to bedside as well I couldn't believe it there I was I just started the environment there's no environment group at Ball State 1989 so I started one it's called Common Ground I'm more worried about the environment and then it's Saint Patrick's Day and the rivers uh dyed green yeah I need to tell you about my new electric car someday um cool all right yeah all right so anyway I just thought aerobic

decoupling I mean there's so much more going on yeah so so I think I think I think Joe Joe Friel kind of uh you know conflated the two or just borrowed the term uncoupling decoupling um and you know came up with aerobic decoupling but it's really just cardiac drift the uh terminology aside any uh infusion that might create the biggest issue here is it's been proposed that when your cardiac drift is below you know a certain amount then that's a sign that your base is fully developed and it's time to move on with your training

um well yeah you're shaking your head yeah I mean we know that endurance exercise training uh reduces cardiac drift but really that's it that's a measure of or a reflection of your cardiovascular fitness right yet uh you know performance is mostly dependent upon your muscular metabolic Fitness and where this arbitrary cut Point uh comes from in the first place is also totally unclear right um you know I think I think it's basically you you pursue the type of training necessary to maximize the capabilities required for your chosen event and you keep doing that until you

stop making forward progress performance wise yes a performance is the end point what did you keep saying it performance is the best indicator of performance yeah the best predictor of performance is performance itself yeah so you know there you are you're a cyclist you took some time off in the fall you trained diligently over the winter you've been progressively increasing the the volume frequency intensity of your training all spring long and you keep working at it you keep working at it and finally you're reaching a point where things aren't going up anymore well you know

it's either you know one of two things to do at that point it's either change your training focus on some other aspect or it's time to go racing right because uh you know you're not necessarily going to make any further progress by just keeping you know keep beating your head against the wall but also you know don't stop beating your head against the wall if you're still improving just because of some you know aerobic decoupling says I should so I think several times we've talked about how you know there's different ways of training to get

the same sort of responses and this fits well with um so last week I spoke with Michael Joyner so I'm going to put his up in a few days times about the sort of the history of endurance training and one of the things he talked about which fits perfectly with this was um you know you talk about sometimes this this concept of all roads lead to Rome so can you end up the same sort of athlete by doing different types of training and he had the great the great comment because he said in the Tokyo

Olympics it was like all roads lead to Tokyo because in the 5 000 meters um you know the the first second and third were all within a meter of each other and they had totally different training so one was like manually long slow distance one was intervals twice a day one was a combination whatever so so I guess that fits what we're talking about right we don't have to sort of obsess about ah I need to be doing this and then even the thing you said about racing he said even the people that that did

long slow distance people said oh well that's all you need to do and he said no they actually would race once a week or once every couple weeks so they are getting that high intensity training right yeah you know I'll credit my wife at this point you know her argument back when she was racing was that you know there is no such thing as the perfect training plan you know you keep it yeah Jimmy Buffett's style keep it between the navigational beacons right within within broad parameters within broad Strokes you know make sure what you're

doing is appropriate and reasonable and then the outcome how successful you become ends up hinging a lot more upon well how much talent you have how much motivation you have you know the environment you're in the you know support you have Etc um and not oh well you know I I you know went and got a laboratory based test so that I could train right at or below my uh right above my LT1 because you know so and so says this is the optimal way of doing so yeah um it's uh and again I mean

you think about the literature the scientific literature and how much people want to hang their hats on you know single studies small ends when really science isn't good for answering a lot of these questions or at least or especially on the individual visual level I mean what we do know what do we know about training well we can we can describe in great detail the effects of training you know down to you know what genes are being switched on what are switched off but when it comes time to prescribing a training program really what we

have are only the big principles specificity overload right reversibility Etc that's what I was going to say as well just you said specifically so I didn't I don't want people to get the impression that no matter what training you do you end up the same because if if you did just do long slow distance then you're only teaching yourself to go slow right and you go then and try and do a you know I was more of a runner so you go and try and do a 10k race you're gonna do crap because you haven't

done anything it's sort of anywhere near race Pace yeah and and then you know we have to think in terms of different sports as well as you said in running I mean the biomechanics are running slow or different from the biomechanics are running fast whereas if you're pedaling a bike I mean it's the same crank length the same saddle height you know the same two Pistons going up and down at about the same you know RPM and all that's really changing is motor unit recruitment uh and okay well I need to train my you know

more difficult to recruit type 2 motor unit so I'll just ride long enough and your type ones will become fatigued but then you know it's different when you start talking about running and then you know again my son's a swimmer and I start thinking about uh what Jim Martin kind of refers to as duty cycle if you look at uh swimming or rowing although they're primarily aerobic Sports the uh the duty cycle is much longer it's like when you turn the muscles on they have to stay on for a much longer period of time because

your stroke rates are lower both swimming and Rowing than they would be you know say your uh step rate while running or Kings while cycling and then you know what are the implications for this as I have to think through it's like well most of the blood flow occurs when the muscles relax not when it's Contracting because when it's Contracting intramuscular pressure is too high and you don't get much blood flow and then you start thinking about well how important is small are the muscle contractile properties as a limiter versus you know energy turnover Etc

so you start getting really into the details here uh with a particular sport but it back to you know back to kind of training zones and and Mike's comments I had long made the point in USA coaching education clinics that on the one hand the adaptations to exercise training are enormously complex you know we alter the expression of thousands of genes right and yet on the other hand from another perspective they're really quite simple everything that happens either increases the maximal force or power that the muscle can generate or it increases the duration at which

the muscle can maintain a sub-maximal force or power output yeah yeah so you have type I say type one let's say you have type A and type B adaptations right and then you could probably subdivide the type B adaptations into those that enhance fatigue resistance during very high intensity non-sustainable exercise you know you're running 400 meters you're doing a cycling pursuit or whatever versus those that enhance fatigue resistance during you know more prolonged lower intensity exercise 10K running a marathon time trial whatever and so these uh the B1 and the B2 may be subtly different

but really in Broad Strokes that's it and everything else is details you know best left under the hood for the exercise molecular biologists right it's like what kind of adaptation are you trying to pursue well there's only three so okay well you know what are the adaptations and how do I induce them well like you said uh over broad spectrum you can do anything from you know very prolonged uh lower intensity exercise or you can do uh you know short intense interval training and how does the muscle respond more capillaries more mitochondria uh you know

probably going to decrease your glycolytic glycogenic enzymes a little bit you're going to reduce your LDH you know a fair bit you're going to produce more glute4 Transporters it's like there's only like one program by which the muscle can respond over very broad swaths you know I mean that's that's one of the things that you know my wife was a track cyclist and I didn't really come to fully appreciate uh cycling as a sport until I got to know her because if you don't consider what happens on the track it's like going to Athletics track

and field and only watching the marathon and not going to the stadium right I mean you need to bring in the velodrome the true match sprinters the true Sprint cyclists the BMXers before you start talking about you know the very far left end of the intensity duration Spectrum in terms of cycling but once you get out Beyond you know a handful of minutes it's all the same thing you know all right great all right so I think we've covered this I was just having a bit of a look at uh some of these Twitter questions

I think I think we've put basically covered a lot of them uh you know without specifically asking the question uh so Jim calains zones imply there are some metabolic anchors FTP is not that CP is not that critical power lactate thresholders I would dispute that um in that again uh physiological responses take place on a continuum uh you could say that they are threshold like even recognizing that it occurs on a Continuum I mean the it is a there is an elbow in the Curve uh it's a fairly narrow range of intensities over where we

can do a pretty good job of maintaining a metabolic steady state and then go just a little bit harder and the uh you know the wheels are all going to progressively fall off um so this is why I refer to as a quasi-metabolic steady state because even if you're below that intensity you can't maintain a perfect metabolic steady state forever you know VO2 will drift upwards even below critical power Etc and you know even if you adjusted the power output in you know measured VO2 frequently with a metabolic cart and kept tweaking the power output

to try and keep VO2 constant um okay power is going to decline but also you like your catecholamines would go up over time your heart rate would go up over time so there is there is no true metabolic steady state you can't remain Kane resting metabolic rate for longer than what four score and 10 right duration of your life right even that low of an intensity can't be maintained forever that's true so so that's what I refer to as a quasi-metabolic steady state but recognizing all of those nuances nonetheless it's it's uh a fairly narrow

range over which things begin to change rather rapidly and because performance is dependent upon the metabolic responses to exercise that becomes the the logical place to Anchor any kind of uh you know training prescription and you know these are not new thoughts these are ideas that have been in the exercise science field for you know as long as I've been around and they keep resurfacing so you can probably find you know didn't David Bishop do a review somewhat recently where he's making the exact same argument you know I'm sitting there looking at going 30 years

ago we knew this why do we need another review well we we blame AV Hill and VO2 max because he got there first in 1924 right and it's taken a long time to undermine you know that perspective um but then then the devil is in the details right okay if we all accept that there is some reasonable Anchor Point in there between sustainable and non-sustainable intensity how do we go about determining it right is it best to base it on physiological measurements I would argue and Andy Jones would apparently agree no it's actually best to

base it upon performance measurements power if it's a measurable kind of thing and then you can get further into the devil in the details there well do you use 95 a 20 minute power you know which is what Hunter Allen has proposed or do you use critical power testing but that's getting way off into the weeds um all right so so um one of the questions was Simon marwood and you've just talked about that you know what is a quasi-steady States you've talked about that uh I'm just I'm just trying to see if we've covered

things now Jose Manuel Valverde ah so he talks about the thing you said already so Dr and then goes San Milan always emphasizes that the introduction of high intensity in a Zone 2 ride negates its benefits as high intensity efforts Hinder aerobic Pathways so talking about the lactate for several minutes afterwards uh this is hard to achieve outside of so if you're an undulating course how much is it of this is relevant so we've talked about that yeah none whatsoever you know you you go for a Strava cream at the start of your three hour

ride uh and you blow yourself to bits yeah the rest of your workout may not be of the highest quality especially if your Fitness isn't really there um so maybe that's not the best plan on a regular basis uh but in terms of the physiology you know physiology doesn't really care think big picture right actually just just back to the thing I asked at the start and I remember we had some emails about it a couple years ago what was this controversy about FTP versus suffer scores the suffer fish we dropped out um I'm not

sure and maybe you're uh mixing a couple things uh waffles quite possibly yeah Wahoo Fitness uh you know they had a whole advertising campaign FTP is dead and then they started hyping for DP four-dimensional power that is you characterize somebody's uh you know exercise or somebody's performance abilities on the basis of their maximal five second one minute five minute and you know sustainable power which is the power profiling idea that I had introduced a decade or more before yeah so yeah um don't have any ethics right I mean this is this is the I'll be

blind this is the very definition of plagiarism right using somebody else's words or ideas without giving proper credit right well it's actually worse because they they said fdp is dead makes no sense does it right they're plagiarizing but they also put lock down the thing they're plagiarizing lots of ways to make money in this world is that a deformational these deformational comments or not okay so um great so I think if we covered pretty much everything I I didn't see all the Twitter because some came I just got up out of bed and I some

more Twitter comments came through but I think we've pretty much covered everything so what would your takeaway I guess if we're talking about uh takeaway messages from this um and thinking about the topic so why all the talk about zone two what would you like people to take away rather than just like yeah I'm gonna tip my hat to you here um because you know the your your motivation for the podcast was the fact that there is a lot of misinformation out there there are a lot of scientists who are getting their hands dirty working

in the field who are the best source of information the closest to the truth right and yet we live in an ivory Tower where we're not incentivized to share with the public instead you know we're incentivized to chase grants build our careers you know pay our summer salaries and I'm I am both a a product and a victim of that entire uh system and I recognize it right um so I'll tip my hat for you for recognizing that you know you have an opportunity here to provide the uh the pipeline the insight into exercise so

in that context aside from telling people you know listen the inside exercise is my favorite podcast the only one I listen to I have a more big picture I would say is uh you know be a skeptical consumer of information and truly consider the source I mean it's not that hard to get a PhD in exercise science right just because somebody has credentials behind their name doesn't mean they know what they're talking about just because somebody is connected and you know has a bunch of really successful athletes doesn't mean that they necessarily know what they're

talking about so be a skeptical consumer and yeah you kind of have to triangulate amongst you know various sources of information but the other part of it is to realize that you know why are you why are you interested in the first place right I mean we're all curious creatures and there are probably many people who even if they aren't going to try and apply it to their own training it is how they entertain themselves they listen to Peter attisha or something like that right while they make their commute to work passes the time while

they're in the car but uh it's sometimes it's also just a distraction and so it's like keep your eyes on the prize don't be confused because the biggest mistake people make is they they basically jump from the latest you know they jump from one training approach to another approach they respond to the latest Guru you know back when uh Lance Armstrong was winning the Tour de France and Chris Carmichael was you know walked on water everybody's like oh I gotta Spin to Win I gotta Spin to Win right um you know so you see you

live long enough you see these things come and go and you realize what matters are the big principles so you know don't don't get distracted by all of the talk um I okay that's great just thinking it's something else I thought of the other day is do people partly want to do zone two because it's easy you know so if you're gonna ride your bike you know I was thinking about the same sort of thing uh although there is depending on how much time you have available people like Steve Seiler have you know uh cautioned

against the no-go zone right spending all of your time going happy hard right um actually going happy hard is a good way of inducing adaptation people ask about well is Sweet Spot you know where's the scientific evidence that sweet spot training is effective it's like do the math dude almost every endurance exercise training study ever published has taken untrained people and trained them in The Sweet Spot because that's what we as exercise physiologists do right we know that it's effective you're not going to get improvements in a college student training six hours a week at

fifty percent of VO2 max right it's just now what do we do we put them you know pretty darn hard you know sweet spot um so uh again though I was thinking about it's like there is some we have three levers we can pull frequency duration and intensity of training right and most people would take frequency and duration together and call that the volume of your training right so you have volume and you have intensity um what is the optimal volume I mean like I said my son's a swimmer my wife and I debate these

things endlessly right they're a high school swim programs here in Indiana We're not in Indiana but Nero in Indiana uh at home um where they have high schools kids training 20 hours a week my son trains 10 hours a week now my wife and I are convinced that he would be faster if he trains more um but how much more you know my on an individual basis the only way to know is to you know do more until you until you crack right but my my experience my gut instinct what have you is that somewhere

around you know the 15 hour a week Mark is where you're starting to trade intensity for volume that all roads leave to Rome right but okay let's say you're choosing you're training 15 hours a week and I want to get better I gotta go hard that's not pleasant right so how much motivation do you have to have to do that you know 52 weeks a year right or is it easier just to ride more and have fun you know and all roads lead to Rome right um so there you know there are more there are

there's you know there's more than one way to skin the training cat what we do know is that intensity is a uh significant factor you can take any highly trained athlete and if you put them into a pressure cooker training program short term you can probably get further improvements or you'll crack them one of the two right but I think somebody like you know your average pro cyclist is probably running around anywhere you know depending on the time of year five to fifteen percent below their maximum performance ability depending upon you know what parameter you're

talking about because it's a job and I've got to do this you know 50 weeks out of the year right and I can't have my nose to the grindstone 50 weeks out of the year uh motivation dries up actually that that reminded me of something to tie together because early on when you're talking about your vo to Max and your lactate threshold I wanted to to make sure people are clear on that and I think this is a good example so show guard 1988 Tour de France cyclist when you look at them over a season

their vo to Max did not change over the season but their performance and their their mitochondrial enzymes changed around percent yeah so that's the good to tie that together the performance is more related to your peripheral yeah you don't actually have to do that much to keep your VO2 max um all right great so just a a a final uh takeaway takeaway just specifically to the zone two stuff what's your takeaway so if someone gets off this and then gets on Twitter and it's like you've got to do everything its own too what would you

say to them what's your Takeaway on that well I think I like my gut is to say the same thing again think of a big picture um that you know the keys to training are the big uh factors specificity overload progression you know reversibility Etc um so I mean I had a a mental map yeah if you were designing the training program for an athlete you know it's like what are the demands of the event from a physiological perspective um you know what are the characteristics of this athlete with respect to the demands of the

event how to best prepare this athlete for this event right or maybe they should pick a different event because they would you know be more successful at something else so that's like an exit from the circle but if you don't exit from the circle you just keep coming back to the same question what are the demands of the event what are the current characteristics of the athlete it's like okay well we've raised your muscular metabolic Fitness about as high as we possibly can we might be able to get a little bit more if you wanted

to do time trials but you're targeting the pursuit you're my wife okay so it's instead now it's time to focus on you know icing the cake by you know VO2 max intervals and then a whole bunch of you know quote unquote anaerobic capacity intervals the go hard puke go home style of training right um because that's what to do a one-off you know three kilometer Pursuit as fast as possible those are the capabilities that you need um so visibility all right and then I was just thinking also if someone was saying what about if I'm

not an athlete I'm not training for I want to do it for health I guess you'd say zone two may not be ideal for that either because even though you might get the metabolic sort of you know you might reduce your blood pressure and cholesterol and Things by doing a lot of low intensity type exercise um I know from with Ben Levine was on here he said you need to do a bit higher intensity to get the cardiovascular responses you want oh yeah ah I mean people are doing it for health uh presumably they're talking

about doing it for the rest of their life right hopefully yeah um so it has to be something sustainable something they enjoy doing and something they can fit into their life Etc uh within that if it's too intense you know you'll burn out and you'll jump from trainer road to full gas to Swift uh you know doing nothing to you know just playing pickleball to back on the bike because the pandemic hit you know Etc but at least you're doing something right um but if you're gonna pick one sport and you're just gonna do it

again it still has to be sustainable it still has to be something you enjoy there is you know the other at the far end of things is it possible to go too hard um there's emerging evidence in a cardiovascular disease realm that you know high intensity exercise could increase uh formation of uh calcium containing plaques in the coronary arteries uh there are some case reports you know like 10 percent out of a cohort of 30 and then several papers right uh where you know people like me who've done a lot of or you um we

may have evidence of uh myocardial fibrosis based on MRI scans uh but at the end of the day if you start looking at you know mortality Etc um there's nothing I mean an acute bout of high intensity exercise increases your risk of sudden death both while you're doing it immediately thereafter but doing it on a repeated basis actually exactly reduces your risk and so despite you know the CAC scores data out there the fibrosis changes Etc um it's still you know unknown whether these things have any true clinical significance well again I I uh Point

people in the direction of Ben Levine's uh podcast on that yeah he'd be the expert yeah not because the good one was he did say that the small calcification of plugs and things but they're more stable they're actually yeah we used to talk about uh vulnerable and vulnerable plaques right yeah so they're more stable yeah so they actually even the people that have the more calcified plaques tend to live longer and that they can be also increased atrial fibrillation but there's still a lot more better more lower mortality so yeah so that's an interesting discussion

all right so um thank you very much maybe I'll have to watch that episode there you go um there you go so thank you very much again for coming on Andy and I'd like to point if we're plugging other episodes you're you know as I said at the start the first the very first episode was with Andy Coggin talking about his nitrates and exercise uh stuff which is really interesting as well so enjoy your holiday and I hope you don't have to spend too much time and annoy your family here with um I got I

got one out of three down now right you're gonna end up in the bad books okay okay good to see you again Glenn thanks Andy see you until next year okay bye bye-bye see you I hope you enjoyed this podcast um please like subscribe pass it on to your friends and colleagues check out the other podcasts thanks again