Framework for Ultramarathon Performance with Guillaume Millet PhD | Koopcast Episode 79

trail and ultra runners what is going on what's happening welcome to another episode of the KoopCast as always i'm your humble host coach Jason Koop and on this episode of the podcast we have a very special guest someone whose work has influenced my coaching career a tremendous amount very specifically in the sport of ultra running and that is guillame mie who i will call gi from now on and i'm sorry for for totally butchering your name gi you knew i was going to do that i mentioned it to you during the recording but gi has this incredible mix of being an endurance athlete himself in particular an ultra marathon athlete doing some of the hardest races in the world including UTMB and the tour de giant and he's also a researcher who has contributed greatly to our understanding and our framework within ultra marathon running and how different things impact performance however this podcast takes a really interesting turn where i'm talking to a physiologist somebody who has a physiology background and we start discussing a lot of the psychological elements of trail and ultra running it was a really fun conversation i hope to have him back on the podcast during a future episode so here we go we're going to get right into it and i'm going to get right out of the way here is my conversation with gi gi you don't you don't know this i'm going to

spring this on you right now but i'm going to tell a quick story about the way that i was introduced to some of your work um it was actually through a mutual colleague of mine in 2015 and um i just started to kind of work with ultra runners more on like a more permanent basis and i was going through this process where i was trying to figure it all out as you're really well aware of like this whole proposition this is what we're going to talk about on the podcast this whole proposition of of determining what the limiting factors are in ultra marathon running it it's a really unknown subject especially when we compare it to some of the traditional endurance sports like cycling and marathon running and things like that and one of my colleagues sent me this youtube video and i say the word video lightly because i think it's just the audio from you actually giving this presentation at the endurance research conference in 2015 and i think this is when you were still in canada and um i listened to it and for the listeners of this podcast i'm going to put a link to this youtube video in the show notes because it's incredibly insightful but it was the first time that i as a coach i like it was as if the stars had all aligned where i could finally say yes this is these these are the answers that i have that i have been seeking to help guide me in how to train athletes for an for an ultra marathon so much so and this is a compliment

to you that for any of our new coaches that come in our coaches that are fresh out of undergraduate or graduate school or whatever one of the very first pieces of continuing education that i give them is that presentation and it's it's brilliant it goes through the whole thing and one of the linchpins in it which is kind of what we're going to start out with is that how running economy might not be that important in ultra marathon running as compared to regular marathon running where we do everything possible to try to maximize running economy this is one of the points that you were trying to make ultra runners carry more muscle mass we use poles in certain uh certain situations that might impact running economy and so for me to you just to start out with that presentation i don't know if you remember or not had an incredible influence on my like early ultra marathon coaching career well first i thank you i appreciate the compliments uh i am actually not sure which uh talk you're talking about because i've probably done uh i've done many presentations probably too many some people would say i'm joking but uh so 2015 i was in canada so i can't remember exactly was it in chamonix or was it in calgary i think it was actually in calgary um calgary yeah but i i can maybe that was the talk i gave in at csep canadian society for exercise physiology okay anyway so thank

you for the compliment well it made it made a big impact on me you might not remember it but but i do and like i said all the all the coaches that i work with they're they're very familiar with you and your work um one of the things i want to get into with the listeners um is this overall framework that you presented i believe is in 2011 or 20 2012 of what are the determining factors of ultra marathon running and it's the way that i can verbally describe something that was that is very visual in this in this paper that you presented is this spider web of all of these different factors that are intertwined with each other that affect ultra marathon performance there's gi distress there's muscle and tissue damage there's psychological and motivational factors and this whole this this whole array of things that i think is important to start to conceptualize so why don't we start start out first by talking about how you first started that how you first started that conceptualization and what are some of the key points of that particular piece of research and of that particular figure in that research that ultra runners can can can take away from um i'm not too sure when i ended up writing this uh this figure uh yeah i guess it's um it was not the the beginning but it was uh not too far after i started to work on ultra marathon so i was i as you said i was like okay so

there's not enough uh not much in the literature about the determined factors of performance in ultra and uh so we probably need something uh slightly different compared to the the classic uh three component vo2 max uh endurance and a crony economy and uh i ended up working uh i mean publishing this uh actually was a viewpoint in general applied physiology and there was this uh this uh figure in it uh and i guess it's not only based on my uh scientific publications or knowledge but it was a combination of uh field experience and and scientific considerations and of course not only my my work but other people's work as well um so yeah and it's it seems actually it may seem it is a complicated figure or picture but it's actually uh much less complicated than it should be i mean the in reality the athletic performance especially in ultra is much more complicated than this figure and uh i don't know if you want to to start talking about the the different factors that that are in that figure but there are there are many many but not enough for instance uh there are factors such as sleep deprivation or pacing it's not directly in the in the figure it's not directly on the graph and it should be uh but that was uh i guess a complicated enough the pacing the pacing can be partly put in the psychological and motivational factors

uh this is this is related but not i could have had uh pacing as another factor factor for say and for the listeners out there what we are describing is a figure from what gi produced maybe 10 years ago now and that figure is a flow chart that describes how all of these individual components of performance so uh for as i was mentioning earlier gastrointestinal distress perhaps uh energy depletion motivational factors how they all interplay with each other and then ultimately result in ultramarathon performance if you contrast that with what we see in marathon performance it boils down to three very simple variables the athlete's vo2 max the fraction of that vo2 max that they can sustain throughout the course of a marathon and the oxygen cost or the energy cost of running depending upon how how you're actually looking at it what we're what what that figure is essentially demonstrating is there's this whole host of variables that actually go into it but what are the what are the main ones i mean you mentioned that you tried to distill even that figure which i still think is complicated by the way um you try to distill that figure down into things that are uh that that that might be more apparent that might be more apparent or a simplified version of it what are the major ones though what are the major points of consideration that athletes should be

taking from that it's it's difficult to say that there are factors more important than others than others uh if you want to be a top athlete you need to consider all of them but uh i will try to to answer your question anyway um i would say that vo2 max even so this is a super long and even so you can sometimes run or walk at uh as low as 40 percent of your vo2 max during during an ultra i would say that vo2 max is still still important not not for not of course because you are you're running close to vo2 max but because if you run at a given speed and you have a high vo2 max obviously you are running at a lower percentage of vo2 max and we know that there are positive consequences of that for instance you are using more fat so this is a simpler one but still i think relevant one uh if you're at uh if you start a nurture on your you you need to to follow the best runners you need to be at 70 percent of your youtube max you are going to use lots of your glycogen and of course you cannot run for very long at that speed because of that reason in partly because of that reason so vo2 max is still is still important and i i guess science show that but the the the most uh obvious i guess proof of that is someone like kilian john he is probably uh one of the athletes with the highest view to max in the world uh and this is not the only reason why he's so good but this is one reason for sure

okay so view to max so any prolonged events you need a high view to max so this is common with any endurance you still need you still need it's still neutral exactly it's still in the endurance domain yeah yeah exactly it's very fondance but it's endurance um okay then actually all the factors more or less but all the factors are common to shorter distances but some are more important in long in longer events than others uh for instance uh even so i'm a physiologist so i don't know much actually uh i acknowledge for sure that that's the the the mental training part is actually super important in neutral um this is um crucial definitely crucial and this is probably something that was one of my weaknesses when i was a runner uh the mental aspect and i tried to i tried to work on that with one of my friends uh who was a mental coach and he helped me uh but um i i i think this is the the longer the distance uh the more important it is and i think i i really like now that i'm 10 years after the end of my career uh i feel like okay i should have done more on that definitely i should have spent more time doing this mental training thing so again i can't say

much more on that because this is not my uh area of expertise but i still believe uh that this is this is actually super important but i i want all the listeners before you continue to go through this i want all the listeners to appreciate the fact that you as a physiologist that's your bias right is the physiology of performance you were saying that even within your own running career you could have spent more time working on the mental game i think that that says a lot because you're taking something that is not within your normal you know wheelhouse to think about and saying hey this is super important and even and even i screwed it up all the listeners should all the listeners should take note of that because i think that that's that is really powerful and it just goes to it just goes to demonstrate how important as you said that component is in an ultra marathon context particularly as compared to a marathon or a shorter endurance event context yes but knowing that is important then of course the the next point next uh step is uh what what can you do what do you do yeah i still believe that there is a large part of uh of it like a pain tolerance that is innate uh you have it or you don't have it but still you can you can work on it and of course it's not all about pentorans but uh part of it is pentorans uh anyway so you you need to to work on it and the problem is that there are i mean it's less true now than than that it was

uh 10 years ago um but the the problem i think is that there are not that many mental coaches there are i not only in the u.s but in france there are there are more now you have a um diploma uh with like on that uh including at the university uh but it's uh it's not that easy to find a good mental coach that actually you also need not not only you need a mental coach but you need a mental coach that knows who knows the the discipline and this is not that easy to find anyway it will come and and okay and then you need to find a coach and you need to accept to spend time including maybe some time to spend time uh at the expense of running and i don't think many runners are ready to do that oh that's a tough proposition i think they should that's a tough proposition especially for ultra runners because we like to train and we like to be in the mountains but what you're proposing is is that we might need to actually take a little bit off the top of the physical training that we do in order to do some of the mental training i had no idea this conversation was going to go this way i thought we were going to talk about physiology the whole time all of a sudden we started diving into psychology that's okay let's talk about physiology it's more right yeah so let's get let's get back to it so you kind of hit some of the the heavy hitters right vo2 max is kind of the king or queen maker right you still have to have a super high vo2 max to be extremely successful in ultra marathon events what else below that would you say are some of the other physiological heavy hitters

so the second obvious one is endurance so endurance uh with the the right definition of endurance which is the ability to sustain a high percentage of your vo2 max right and so this is of course endurance having a good endurance is important uh for any distance like even if you're in a 10k you need a high high endurance uh but compared to ultra this is the same word but this is not the same determining factors of endurance so for instance for if you're on a half marathon or even marathon you need a good anaerobic threshold you need to be able to to be able to to be to to have your anaerobic threshold or your critical velocity close to your your guter max in ultra i don't think we care that much about the anaerobic threshold what we care about in ultra is in my opinion and of course we discussed but there are two main points the first one is your ability to resist to muscle damage or lower limb tissue damage uh and the second point is we already started to talk about how you already started to talk about that is a gip stress so those two points are super important to be able to run for 10 20 or 40 hours or even more if you're running the tor de jane so left tor de jane for those of you that that are uh you guys everybody missed our off air conversation we're talking a little about about tor de jane before we jumped on the podcast maybe we could use that as a

as a little bit of a case in point of what i want to talk about now which is a lot of this muscular damage that occurs and all ultra runners and mountain runners will be familiar with this sensation of having dead legs towards the end of a race especially races that have a lot of vertical gain in particular vertical descent and we see this we see this amount of muscle damage pop up in the physiology of runners runners when we when we uh when we poke and prod them after races or sometimes during races which is some of the research that you that you've been involved in let's kind of first just describe how that damage like what that damage actually looks like like what's going on at the level of the of the muscles and then we can talk about potentially some training strategies to mitigate it because that's ultimately what people are interested in is how do we prevent these things in the first place but what does that look like physiologically when we start to see some of this muscle damage damage crop up in ultra runners so this is uh as you said this is related to um to the repetition of micro or eccentric contraction uh even so it's probably true that in downhill you have more down here you have more muscle damage but in ultra you are running uh of course super slowly and uh or at least you should even even in the first downhills and if you do that you may be able to minimize uh muscle damage so that in the end uh flats ultra and

ultras with elevation lots of elevation and lots of downhills in the end i'm not sure the the consequences in terms of muscle damage uh are that different uh but anyway so uh either flat or uh you're trapped with uh lots of elevation you at some point you will get some uh some muscle damage and the difference with the shorter distances is that this is so long that you start to feel the consequences of this muscle damage during the race if you do a let's say a 30 minutes downhill run only 30 minutes or even less 15 minutes full speed uh this is not such an issue you will get massive muscle damage even in 15 minutes if you go full speed downhill uh but you don't care because you will feel the consequence in the the hours or the days after the race but in your trial you will you will feel the consequences during the race and this consequence is the inflammation that start to to take place to repair your your muscle damage right i guess it's not only the the muscle it's also tandem and all basically all tissue in the lower legs but let's call that muscle damage um and uh yeah so this is not good because inflammation is painful as you said and in the end i don't know if we have time to to talk about the flush model but in the end everything is um is under the supervision of the brain and of

course the brain the the main factors that that's uh trigger the the brain response is the the perception of effort or pain okay so the listeners will remember a really great podcast i had several weeks ago with uh roger anoka and we talked about a lot about neuromuscular fatigue so since you brought it up we're gonna go we're gonna go down there i always feel that when we start to talk about areas of the brain though that people automatically tune out because neurophysiology is incredibly complicated the vocabulary is even weird to work around and people start to tune out let's make it simple let's make it simple let's make it simple then so what is neuromuscular fatigue stuff like that and people will understand let's make it simple what is neuromuscular fatigue and why how does it show up in ultramarathon running okay so neuromuscular fatigue uh is can be defined as a reduction in maximal performance that's a very basic but still i think valid definition for instance if you measure force before the race and immediately after the race uh you will of course observe a decrease and what we observe is that depending on the duration you you have a kind of a non-linear increase of this uh force strength uh and it plateaus for like 100 miles or even probably a bit shorter 100k

maybe it plateaus around 35 to 40 percent of your maximal force initial maximal force uh this is valid for the criceps and the plantar flexors the cows roughly it's uh 35 to 40 percent in average of course right um and we have done several studies and we consistently showed that so i think this is uh we i think we can accept this uh before before you go on though let's describe the studies because people are going to appreciate how you actually get this data a lot of which you've collected at uh the ultra children mont blanc just how what's the setup of it so because i think that that will help under i think that will help the listeners understand what is actually going on at the level of the muscle if they understand what the actual research protocol is very very simply very simply put like what did you have the subjects go through well it depends which study you're talking about because i've been publishing on ultra for since 2003 uh meaning that i'm old so but and we have done now the reason i'm saying that is that we have done both labs and and field studies the field studies that's what i was referring to yeah okay field studies because we also that we also did a study i think this is this is this is nice to uh or maybe not nice but fun to to tell to your listeners we we have done a study when which consisted in having uh 14 people running 24 hours on the treadmill yeah so i don't know if you

maybe you've not you've not seen that no i've seen that one it was so fun anyway so this this is uh usually when you when you want to study ultra and to go back to your question yeah we go on the race uh and we've done mainly UTMB but also another race that is probably less known in abroad uh which but it's super known in france it's called lagran pose detemplier it's a shorter race it's only 65 or 120k so it's not 100 miles but uh still that actually my first study was uh at this race and i want to take the opportunity if you have two sec uh jason to to thank the organizers so both uh the organizers of the templier or dylan jilbert and the organizers of the UTMB catherine and michelle polity because without those guys uh we cannot go and do our studies so they they have been super helpful so i just wanted to thank them anyway so to answer your question finally uh we go there we recruit people of course ahead of the race uh most of the times we test them the in the in the lab the months before the race and then so it's the first visit then they come uh at the race and we have our lab uh close to the finish line okay starting and finish line and we test them in the two days before the race so we have the the initial values uh okay and then they do their race we usually we don't do anything we may want we may sometimes

record like heart rate or gps or stuff like that but usually we don't do much during the race and then immediately after they are done with the race they come back to a lab which is a lab in the field uh and so at the UTMB it's uh they need probably five minutes to walk to the to the lab and then we test them again as soon as possible it takes time but uh of course you do not recover in in in five or ten or 20 minutes after the race like the UTMB so we test them after the race and the fatigue is the difference between the three so measure within the two days before the race and the post which is immediately after the race and what you're asking them to do is something maximal i think that that shouldn't get lost right you're asking them to do some sort of maximal voluntary contraction or maximal force both before and after running a race like templier or UTMB yeah and plus we do a stimulation like electrical stimulation so we we shot them with electricity or magnetic field at the cortical level so we put a coil on the motor cortex and or sometimes we ask them to do a sprint on the bike uh six or eight second sprint so we are we are we are not nice that's but they they they come back so they should enjoy that let's see that's what i was trying to that's what i was trying to get at you're asking them to do all this really hard invasive stuff right after they finished a really difficult race so kudos to the volunteers for this but it does really illuminate a lot of things that we

previously didn't know in ultra running one of the things is just what you mentioned is it's it seems to be that this amount of force decline plateaus off after a certain point meaning we get to a certain point in a race and you don't from from at least that one perspective that you are measuring it doesn't seem to get all that much worse why do you think that that is it's actually uh even more than what you just said after uh like the torsion we measured that uh the force decrease was actually uh lower than 40 if you consider fatigue as a reduction in maximal strength the conclusion could be that it's uh less fatiguing to to run 200 miles than 100 months nobody's gonna believe you on that by the way that's that's no this is no as i said this is one of the limitations probably of our definition uh because of course it takes more time to recover after the but um anyway they probably the reason for that is that uh during the torsion you stop to sleep at least most of the runners they stop to sleep which is not the case for the for a shorter race uh anyway so yeah this is uh we ask them to do maximal maximal contractions and this is as i said the the definition of fatigue of nervous quality uh so is it fair to say gi that in your estimation is neuromuscular fatigue specifically one of the

primary culprits of overall performance decline in ultra running uh of course it plays a role it is important uh but actually it cannot explain all the performance deterioration in rain and this is actually the reason why i i uh decided to to go with this flush model uh because i uh when i published this uh flush model paper in sports medicine i had already published quite a few papers on on nervous core fatigue and i was like okay as a runner there is there is some not wrong i cannot say that there is something wrong but there is it now it doesn't explain everything so we need we need something broader larger to extend performance but definitively neuromuscular fatigue is part of it and particularly the the the central component so the central components uh the central fatigue is um the inability of the central nervous system to drive the muscle and maybe i can take two secs to to explain that uh so how can we determine that simply by using electricity so we ask the subject to do to contract their muscle maximally and when they reach their maximal force we superimpose an electrical shock and we examine the response the force response if you're able to increase the force a lot it means that the subject was not able to fully

drive his muscle or her muscle and uh usually before the race there is no no increase it's uh they are they are in good health they are trained so they are able to to recruit everything all every single muscle fiber is recruited before the race but after the race not only the muscle fibers are damaged or fatigue but the central nervous system is also fatigued meaning that uh the the muscle fibers that are in bad shape they are not fully derived anymore and we so after the race when we stimulate of course the force when they they try to do their max the force is much lower so as i said 40 percent lower but then when we stimulate we're able to increase the force more than i mean no not more in terms of absolute force but uh we can clearly see a superimposed force meaning that the the brain was fatigued i don't know if if it was clear but this is actually quite important to to to consider that the it's not all it's not all about muscles it's actually after an ultra and especially ultra running this is less true in cycling but after ultra running uh the the central nervous system really suffers and maybe one of the reasons why the the brain that it's not the brain it's the central nervous system but let's call it the brain uh is not able to fully drive the muscle anymore is to maybe to protect the body right because we are so we are so fatigued that okay i don't it's like okay i don't want to to push more than this is this is

like too dangerous for the for the body of course this is an interpretation but the reality is that we have a huge what we call central fatigue or neural fatigue and the way that just to describe that in another way for the listeners the way that you're trying to figure out if central fatigue is playing a factor is you you're inducing an electrical stimulus while you're asking the athlete to produce a maximal voluntary contraction so you're essentially finding out what part of the force decline is responsible for central fatigue by subtraction right because you're introducing it after the fact when we want to examine the muscle fatigue so there are two parts the central fatigue and the muscle or peripheral fatigue okay uh to to it is quite easy to measure muscle fatigue meaning that you don't want to have the influence of the brain you just as a subject to relax and you stimulate the muscle and you you do that before and after the race as i explained and of course after the race when you stimulate at the same intensity the force response is lower and this is due to muscle fatigue so guy we we got off on a little bit of tangent talking about neuromuscular fatigue in this in the differences between central and peripheral fatigue and how we're measuring it but what we originally wanted to talk about was what was muscle damage so let's backtrack a little bit we know anybody who has done an ultramarathon knows that there's a tremendous amount of muscle damage that goes on because you can see people hobbling

around after races and they're just sore and they're just kind of a mess but we know that there's actually like a clinical way that we can look at this where we use biomarkers that indicate muscle damage primarily cpk and we measure this after races but how does that actually impair function so we have all this muscle damage what is the performance consequence of that while that while the runner is actually running an ultramarathon which could be you know a day or several days in length well first of all i don't think cpk is a good index of muscle damage i know this is a the the index that uh everyone uses uh but this is very imperfect um that we don't have uh much better ways to assess it so okay let's go with blood sample um anyways uh the the technique that i explained the the muscle stimulation is another way to examine indirectly uh muscle damage slash fatigue um anyway so the question is uh why is it important um and sorry i will have for it to go back to the flush model again because and i will come back to do muscle damage in a minute but uh this is not in my opinion this is not a direct consequence of muscle damage because even so the the muscles are really damaged after neutral especially if you're not like super

well prepared uh they are still in good relatively good shape if i go back to to my 40 decrease in maximal voluntary contraction okay 40 seems a lot and it's a lot actually but uh you can also consider that you still have 60 of your maximum and with 60 of your maximum you can run quite fast right and much much faster than what people do during during the race so the constant the the problem of muscle damage is not the damage itself is the inflammation and the pain and you are not running faster not because your muscle cannot do faster you are running slower you're you're decreasing your speed simply because your brain is telling you to do that because if you you know that if you keep going at that pace this is going to be super painful and you are not able to tolerate that pain for the rest of the race so you you you pace yourself to be able to to reach the finish line so it's not a function this is this is sorry this is really why you need to minimize muscle damage is to minimize the pain so it's not a functional problem it's a perceptual problem which which which are related of course right because the perceptual is related to the functional the function so if you are able to minimize the the muscle damage then you will improve performance and when you were talking about uh running economy a while ago now uh and saying that um i said that running economy is not that important this is not i don't think

this is what i said i think what i said is that there is a kind of a trade-off between running economy and endurance and in particular muscle damage that's this is so important that sometimes you need to sacrifice and that was actually the title of the paper can we sacrifice running economy to improve overall performance and this is the point this is so important that you may need or it's not that you may that you need to do everything you can to reduce muscle damage and sometimes this is at the expense of running economy let's let me give you a couple of examples if this is clear is that clear yeah 100 what i'm thinking of is is like this high arc it's almost like a hierarchy of performance needs where preventing muscle damage is just higher on that chain versus running economy that's the way i view it yeah it's it's a it's a fair comparison i think uh okay so a couple of examples where you may need to sacrifice uh running economy to improve overall performance basically to improve endurance if you minimize muscle damage you improve endurance of course you're not going to improve your view to max but you improve your ability to run at a given percentage of your max for a longer period basically uh one is uh poles using poles we know that this is even so now they are super light uh but still using poles probably uh worsen a little bit your economy but this is so nice to minimize the

the load that you put on your legs that i actually don't understand of course if this is allowed by the the rules but if this is i don't understand why people are not using them uh maybe this is not true for killian johnnett but for 99 of the the runners this is true because you are able to to to share the the loads the workload between the from the legs to the upper body and anytime you do that it can only be positive for the overall performance this this is my this is my opinion at least uh another example which is and the polls are probably the best example but other examples are for instance flexibility we know that if we are too flexible uh this is not good for running economy and i'm not saying that people should i've never said that uh but this is true that if you are too flexible um at some point this is going to deteriorate your running economy but this is probably a good thing for your ability to minimize muscle damage because you tend to to how can i say that to smooth all the the the big force at each stride uh and there is no like super clear evidence but i i believe i believe in it i believe this is true uh another example is running shoes you may want to of course if you're on a marathon you want super light shoes right for a neutral marathon yeah maybe this is a this is more debatable uh it's not uh it's not really in terms of uh like muscle damage but maybe in terms of

comfort if you you need you need very comfortable shoes if you're on a neutral and even if there are a bit heavier than um lighter shoes uh that that's okay i think you need to accept that and okay you are going to deteriorate a little bit your economy but if this is again this is a trade-off that you have to make to to improve your performance overall rpe is so important again so if muscle damage is one of the more important considerations to try to prevent in order to maximize ultra running performance aside from the flexibility piece that you mentioned earlier what are some of the training components that you feel that runners should be taking on during their day-to-day month-to-month training in order to prepare them to mitigate all of this muscle damage that's going going to occur it's pretty simple actually and everyone does that but you really need to to emphasize that this is very very important it's a running downhill you just need to accumulate you need to accumulate a negative uh elevation that there is you can do strength training you can do some eccentric training in the training room that that helps for sure um but uh at the end of the day you want to do specific specific training and specific training downhill in particular that's your heavy hit this is why i proposed uh many years ago i

don't think this is famous in the us but in france it's quite famous what i call the shock weekend the shock weekend is that you have to go if you prepare a race like the UTMB for instance and and you don't live in the alps at some points you need to go and and probably you better go several times in the months before the race in the alps or in the place in the mountains at least and to do two or three days this is why i call that a shock weekend because usually you go in the weekend to to truly shock your muscle and and by shocking i mean running downhill and doing thousands and thousands of meters of uh down here running uh there is no no other way to to prepare your muscle and if you do that you will beneficiate from what we call the repeated bout effect and we know that this is actually the first adaptations are quite quick but then you you need to do more than one time for sure and then after that it's uh probably less obvious but you will keep increasing your your resistance to muscle damage and there are we could we could uh go into details about the reasons why this is happening but the main reason is probably that you simply um strengthen your what we call the the cytoskeletal and the basically the muscle fibers becomes stronger we're on the same page and those of you that are not watching the youtube version of this i've got a you know grin on my face from ear to ear because we have talked about

this a lot on on this podcast and it is one of the most common coaching questions that i get on a weekly basis it's from athletes just in the situation that you described i'm going to a mountainous race and i don't have mountains to train on what do i do and athletes are notorious for trying to contrive all of these different ways that they are going to cope with the downhill they use box step ups and some use strength training and some running up and down stairwells and i've always said that the most the most effective way is to design a series or at least one training camp where you go out you go on the mountains and you get all of that downhill running in a natural environment that is going to be your heavy hitter in those situations all those other things they might you know maybe they help a little bit around the edges you know that's going to be debatable but try try to be shaking his head right now i usually shake my head when i see that as well it might be a something's better than nothing situation but maybe but your heavy hitter i guess is the point that i'm trying to make is try to get a training camp in a mountainous environment that is going to do a lot even if you can just do it for a few days or a couple of times for a few days and and i think a training camp is is great but if you can do several mini training camps this is better because you do those short weekends so you can call that a mini training camp like a three days of training where you do these heavy loads and

particularly downhill uh actually both uphill and downhill of course if you run you you run ups and downs uh or you woke ups which is actually another point we can discuss it's not muscle damage but this is another super important point in my opinion and this is another reason why you need you need to do those uh those short weekends uh but anyway if you do those short weekends you go three days for instance you do your training camp then you recover you take three weeks to recover so that you repair your muscle damage you they they get stronger then for the next short weekend you can go faster because you are more resistant so you can you can push a little bit more especially down hills and then you get additional muscle damage you repair and you you get even stronger more resistant etc etc and here's the here's the important point for athletes is the first time you do one of those shock weekends the overload is going to be achieved just by running downhill you don't have to do anything special you just run downhill because you're not if you're not used to running downhill just running downhill is going to be far it might even be too much overload in some situations yeah maybe uh start by walking yeah there you go yeah exactly if you're if you're really uh not super well prepared for a short weekend you can still go and you do uh basically hiking exactly that that that may be enough for the for the first one exactly but here's what people want to do is they want to go out there and they want to bomb down the downhills because they've all seen the super sexy videos from solomon where they're you know jumping

off of rocks and you know screening downhill as fast as they can they want to emulate that as much as possible but from a training perspective sorry and then the second day they won't be able to to uh to walk anymore exactly exactly this is stupid exactly you need to even so this is only three days you still need to pace yourself for the first sometimes even two days is enough but you need to pace yourself for the first day so that you can do a lot the second day and maybe this at the end of the second day you can start to run because then that's okay you're done with the short weekend so you can you can you can run faster if you like or if you if you can which is uh which may be the problem there you go okay enough about that so we've got this we've got this weekend or we've got this like plausible training scenario that we can set up for athletes that don't live in mountainous areas they can go do a training weekend or a series of training weekends i think that's a really a really poignant way to do it that we can derive from the research you've mentioned this a few times and i'd be remiss not to to to let you opine on this uh kind of as we conclude this podcast but this is the flush model that you keep mentioning that the listeners are not going to be familiar with if you're if you're indoctrinated into the scientific literature and especially a lot of the work that you've done gi that this is going to be a familiar term but most of the listeners with all due respect to you this is going to be totally foreign to them so why don't you take them through this flush model that um that you've mentioned a few times on this podcast and why is it relevant or why why should it be

relevant for ultra runners sure i'll try at least so as i said uh i guess as a scientist i could live with the nervous flow fatigue as a runner this is definitely not enough so i needed something else so i needed a very sophisticated model that's why i chose a flush toilet of course i'm joking and part of the reason i chose a flush toilet is because it was uh at least according to me and my wife would disagree i thought it was fun it was funny maybe it's not but i i thought it was funny so i could have used another another tool probably another model but i thought the flush toilet was a good one and actually it's very appropriate anyway so the the idea is to as i said i think performance is basically only determined determined by the perception of effort so as we just discussed you need to do everything you go to you can sorry to minimize muscle damage it's not to minimize muscle damage per se it's because you will minimize your rating of perceived exertion if you do that you will have less inflammation and the the sensation from the muscle that are triggered or are carried out by uh what we called sensitive fibers will inform your brain less if you are able to preserve your muscles better and again one good one good way to do that is this training or the best way to do that is training anyway

um so everything is based on rpe rating of perceived exertion and in the model rpe is actually the level of water in the tank okay so basically the model says that everything you can do to minimize the what the level of water in the tank will improve performance and vice versa and it's not only what is happening during the race like we just described with the the muscle damage but also before the race because contrary to what most people will think you do not necessarily start the race with an empty tank of course as soon as you start running you will see the the level of water increase because uh because of fatigue because everything you can imagine um and it's not on not only actually about pain that you see the rpe increasing when you start to fatigue is also because since your muscle fibers start to be fatigued and and damaged to run at the same speed you need to increase the number of muscle fibers that you recruit right since less each single fiber produces less force you need more to do the same right so if you increase your your central command to your muscles there is a copy to yours to your uh somatosensory brain or cortex that tells you hey this is this is more difficult so there are both sides now this is what we call the feed forward mechanisms plus of course

the feedback coming from this afferent fibers that i was talking about so those two mechanisms together explains why you increase your rpe when you start to be fatigued right so in other words for the model it means you start to increase the level of water in the tank but to go back to my first point sometimes you don't start the race with an empty tank and i don't know if you can guess what i have in mind but basically there are two good examples that are probably very similar the first one is that mental fatigue is is mental fatigue so of course we are not asking anybody to to do math before before a new job but sometimes the week before you may have personal problems right you are not so because of your work or your family or whatever yeah and this is going this is still mental fatigue so you're not very relaxed and when you start running you probably start with already some more difficulties than what you should be or you should do and this is uh so basically it means that you you start the race with some water in the tank and of course it means that you are going to reach the the top and i go back to that in a minute uh earlier and the second example and it's probably even more relevant to ultra is sleep deprivation um we know that if you there's many studies uh including some of our studies that show that if you are

sleep deprived uh you will have you will deteriorate performance not because you have a low of u2 max or any physiological impairments but simply because you feel the exercise is harder you have an increased rpe so again you start the the race with a with not an empty time and this is this is this is very bad so this is so important that people they really need to i guess most people they will understand that okay i need to sleep well the week before the race but i think people underestimate how important it is so i think people should do what we call sleep banking before new tram on top this is very very important and the model to go back to the flush model the model also explains that i could give you tons of other examples but i think those are good examples but i love the i love the fact that we're using a physiological consequence that you are seeing out in the field right neuromuscular fatigue is a big deal in ultra running we're using we're using that which has been measured in the field and you've measured in the lab and measured in your lab that's in the field we talked about earlier to come up with really practical solutions for that that athletes can actually put into place and that's bank sleep right sleep i have my athletes extend their sleep for two hours usually in the weeks leading before the race very smart i'm not sure everyone does that yeah i think that that's a really easy practical and most people are trying to double down on their training at that time that's usually what's the complicating factor but this point of going from we see this happen in the race how do we prevent

it in training is really practical we see neuromuscular fatigue happen in a race how do we prevent it in training one of the ways that we're going to prevent it in training is we're going to do camps like we talked about earlier another way that we're going to do it is in the days leading up to the race we're going to sleep more and we're going to reduce the amount of stimulus that the athlete is having to kind of deal with in advance of the race and i am thinking of the classic american that goes over to UTMB and gets completely overwhelmed by all of the hype and hoopla surrounding that race there it's it's a race none unlike any other event that we have here in the u.s and they get completely absorbed in everything that's going on in chamonix and what that does is it fills the to use your analogy it fills the tank up more right exactly exactly and the last point maybe if i can if i may um is this model also explained the the mantra training part that we were talking about because uh another another part of the model is that uh the model says it's not the model it is the relative that you usually you don't die from running right you don't die from fatigue so you have you have what we call a security reserve basically the water never overflows correct and so this security reserve if you if you're able to minimize it then this is another way to improve performance so you need to reduce the the speed at

which the level will uh the level of culture will increase in the tank but you can also try to go higher and by doing mantra training you also do that if you if you're able to to basically what you want to do is to finish the race with the highest possible level of fatigue not the lowest possible level of fatigue 100 here's how i've described it to people and this is based off of the research of uh some uh some sports psychologists that have long preceded any of us is that your physiological capacity determines how much total work you can do but your psychological skill set determines how much of that total capacity that you can actually tap into and so when you're talking about the when you're talking about the reserve which is the difference between the very top of the of the water tank and what you're actually what you're actually doing the top of the water tank would be how much total physical capacity you have how close you can get that water level to the very top has everything to do with the psychology that you can deploy during the race itself yeah so the maximal capacity is what you will be able to do if if a bear runs after you this is your maximum but usually you don't do you don't do that much even even in the race even at the UTMB if you're super motivated i think you've just this is this is the limit you've just designed your your uh next field study right there you're gonna

introduce some some sort of i'm not sure ethics will agree with that but if they do all right this has been great man i gotta let you go we're gonna have to have you back on the podcast we could dive into more i had no idea this was going to take on just as much psychology as it was going to physiology and i think that says a lot for that particular field especially coming from somebody like you um i will yeah there are many things of course sorry to interrupt there are many things and actually uh when we when we prepare that you asked me to talk about uh running economy and and of course we could have to talk about uh uh running economy biomechanics etc etc but uh we'll do that another day we there's always more time my friend and uh i'm glad i'm i'm glad that you're now agreeing to come back on the podcast the listeners will definitely uh appreciate that i'll have links in the show notes to everything that we talked about all the research papers and probably then some including the initial uh talk that where i was introduced to uh your work in addition to that guy do you have anything for the listeners in terms of where they can find you or any research that is coming up that people can get involved in yeah so i have a personal website so it's a 3w dot kinesiology so g ui dot uh com uh i i believe this is i'll put a link to that in the show notes too yeah this is this is dot com uh so they will find uh like uh all the scientific articles about ultra running uh that i have

published uh it's a it's free access uh i'm not sure i'm supposed to do that but uh plus uh no most of them are it's it's legal i'm joking and uh and additional uh videos so some of them are in french but uh most of them or many of them are in english so i guess french english perfect and yeah so go to my website and they can also follow me on twitter which is uh go follow g on twitter you're good you're a good twitter twitter follow i have learned a lot from following you and also being a part of some of the banter that goes on in the thread so i encourage people to do that as well g thank you very much you got one more thing sorry one more thing if if you allow me i would like um i hope people uh i'm not sure it will be very helpful but i i would love to uh have all the people listed in your notes all the people that have worked with me on on on all the different uh research we were talking about listed in in your notes if you define me that because i think this is super important to acknowledge that uh science is not it's a teamwork and uh i i think i want to do that if you i can 100 absolutely send me all the names and i will definitely put them on there thank you yeah thank you again bye bye all right folks and there you have it much thanks to gi for coming on the podcast today we have to have

you back i could talk to him all day i hope when i am over in that neck of the woods hopefully this summer we get to sync up for a trail run i would much appreciate that appreciate the heck out of all the listeners today if you have not already done so go ahead over to apple podcast and give this podcast a rating or a review it helps me spread the podcast a lot and it also means a tremendous amount to me personally i love it when i see those reviews come in that's it for today you guys we will see you out on the trails you