Performance Testing for Ultrarunners with Dr. Philip Skiba | Koopcast Episode 128

trail and ultra runners what is going on what's happening welcome to another episode of the KoopCast as always i am your humble host coach Jason Koop and i'm excited that everybody is here with me today because we have a killer guest lined up on tap for you all it is the guest whose work i have been familiar with and i've utilized as a coach for many many many years probably 15 years now that i'm actually thinking about it it is none other than dr philip skiba and for those of you that are unfamiliar with phil he is one of the most renowned endurance coaches in the world today playing counsel to some of the top athletes including paul radcliffe and elliot kipchoge he is an absolute mastermind when it comes to physiological testing and using field testing to determine training ranges for athletes and most notably and most impactful in my coaching career he's also an author his previous two books i have bought countless times for our coaching staff as they are getting up to speed and his new book that just came out that i cannot wait to dig into scientific training for endurance athletes is an absolute must have on any serious athletes and any serious coaches library i wanted to bring phil on the podcast today today to discuss one of these

aspects that i'm really fascinated about and that is the use of physiological testing to inform coaching practice this is something that i have a an extensive background in with our laboratory our physiological laboratory here at cts and phil also happens to be like i said earlier an absolute mastermind in this where he has all types of tools available to him to help inform what is going on with athletes and how he uses those might actually surprise you we get into that right on the onset of this podcast and one of the things that i have come to appreciate about coach phil the most is his very pragmatic approach to how he can use data and physiological testing in order to inform practice and help guide athletes so with that as a backdrop i'm getting right out of the way here is my conversation with dr philip skiba all about testing and how we can better help athletes the book finally came in congratulations on it yeah yeah i'm uh i'm pleasantly surprised at how well it's doing uh good i think all of us who publish a training book because this stuff is inevitably boring we have such low expectations of how it's going to sell and then for whatever reason we end up uh uh we end up uh end up outdoing ourselves so to speak i mean my first couple of books like sold really well yeah and then when i went to work on breaking two i just didn't have time for everything i said i

ended up taking it off the market because i wanted to update it anyway and so so yeah i didn't have any books on the market for for more than five years for for twenty six seven years yeah wow like my old book went up to it was up like eight hundred dollars on uh on amazon somebody's old coffee right supply and demand right there's no supply and no demand it must mean that the price goes up so yeah when i rolled out the new one it was just like it was like kaboom i couldn't keep it in stock for about three months and so finally now i'm now able to look at a match i'm now now now able to match it's okay so yeah well congratulations it's a it's a it's a it's a really clean work the previous two books i i've probably bought a few dozen copies each four for our coaching staff when they come in at various times just because it's a good resource to get them them grounded you know and make sure that we're all speaking the same language and i can't profess to have read the entirety of the second book already but i just looking through it it looks like it's pieced together in in a in a similar fashion one of the things i'll also give you credit for is what you skip over which i think like speaks to the level of the audience that you were intending right like you you deliberately skip over some stuff it's like listen you guys got to look this shit up yourselves yeah exactly you know um but but yeah i mean it was i mean it's probably i don't know probably half

new material half old material that's what it seems like so um so i think it's i think it's a pretty good balance between the between the old stuff and the new stuff and so i'm so far people are reviewing it pretty well so so i'm happy good good for you well i wish you the best with it we'll talk about various pieces of the book here and there as it as it kind of gets weaved into the story but i really want to take the opportunity and speak to you a lot about uh performance testing and how we translate that in the real world i think your experience that you have as a coach and in particular with the types of athletes that you work with and also your experience with breaking two in the long-term listeners of this podcast will remember i had uh brad on the podcast who was the head of that project uh maybe six months ago or something like that um yeah yeah yeah he's he's great he's actually been interfacing with a few of my athletes on other projects as well it's a very small circle that we that we weave um but i think that you're in a really unique position to kind of help solve one of the problems that i have always struggled with in trail ultramarathon training and that's just how to make sense of the data that's coming across the wire that we see that we see in the field in terms of how do we evaluate workouts and how do we figure out what the demands of the individual events are and i know a lot of uh physiological testing that we can do in a laboratory setting that can help

collaborate those numbers and the the phenomenon that we actually see in the field can help uh tell a little bit of that story but but before we get into it too much just take a second and describe like what like what you do professionally for the listeners so they can get to know you a little bit better yeah so you know i wear a couple of different hats in my life um i run sports medicine for advocate aurora which is one of the largest uh healthcare systems the united states um and so as part of that i'm seeing patients every day i also run uh we have three different physiology laboratories two full exercise laboratories with metabolic cards and treadmills and ergometers and all that stuff and then two biomechanics laboratories um one of which is combined with a phys lab um where we have a 10 camera vicon motion capture system and force plates in the floor and um and the whole nine yards um and so that's kind of the fun part of a medical job because i get to test athletes like the test you know just just regular people off the street um i get to combine that with physical therapy and pulmonary rehab even for our post-covid people um so all that's really exciting um the other part of my job is you know my it was just a bit separate is all the consulting work i do in elite sport um and i work from everyone from paralympians to elliot kipchoge to um a lot of professional triathletes and things um in a variety and a really a variety of different sports around the world um so yeah i do a lot of stuff well when i talk to people like you i'm like how you like fit it all in because just to take one of those and it's a full-time job

yeah i mean it requires a lot of time management um but you know one thing when the one thing often plays off of the other you know like for example for breaking two you know my health system got so much good publicity from that they were willing to let me out of a lot of doctoring type stuff to allow me to go to go full on with that because you know they liked having a national geographic movie with one of their doctors uh co-starring so uh so yeah it's a lot of fun i'm a lucky guy i i really enjoy what i do every day well and so and it's because of that background that i think that this is the perfect setup to talk about how we can take testing and i was going to mainly limit it to physiological testing more in the interest of time but if we go down some sort of combined biomechanics and and metabolic testing rabbit hole by by all means the floor is yours but i really want to i really want to explore that area and um talk about how trail and ultra runners can can take information like that and make sense out of it and apply it in a real world uh applicable setting this is one of those sports it's really interesting i was actually just uh talking uh speaking just before i got on the phone with you with one of my colleagues from uh training peaks who i'm sure you're familiar with is dirk friel and we we were reminiscing about the power meter revolution in the early uh kind of in the early 2000s we're cycling we're cycling power meters became you know we were always used in the pro peloton before then but they certainly never raced with them because they were just too darn heavy

but the combination of the pro peloton being so seclusive about what they were doing for obvious reasons now and now in retrospect uh combination of that and the fact that these power meters became more accessible and more affordable we ended up having this really powerful tool that we could use in the field to prescribe training analyze the demands of an event analyze the demands of any sort of other other training ride and it really informed our coaching practices like no other like no other revolution and i think in the trail ultra space there's no real equivalent of that because the surface and the duration kind of confounds all those different variables but i think that there's lessons to be learned so let's kind of it's not a reverse engineering of a problem it's kind of engineering it from the get-go why don't you describe some of the tests that you would take an athlete through that came to you and said hey listen i'm an endurance athlete i'm a you know ironman triathlete i'm a trail ultra runner what tests would you recommend that they would do and what's the value proposition essentially that the that the athlete would get from that i got i got to be honest with you and i say this is a guy who you know does a lot of testing every day um 95 athletes don't need any testing at all um and uh and people don't often don't like to hear that because they watch something they watch what we did with the guys in breaking too i mean that for me that's like the best advertisement there is not like skiba hook me up to the middle of the park cart let's do all

this stuff it's like hey oh hang on a second hang on a second um because if you're tracking your data on a day-to-day basis and you're training hard and you're racing once in a while um and you always got that gps on you're always running your power meter i can tell a tremendous amount from that um and because uh because the first the first question you always ask is is your goal even reasonable um and and and i can tell you like over the years you know especially once jim started getting in these kind of fake metabolic parts that you can buy for a couple thousand dollars right um and then someone comes into me and says oh my vo2 max is 70 why can't i keep up with you know you know name name the pro cyclist of your choice and i was like because your your vo2 max is not really 70 because you were sold a false bill of goods um so so that's always the first thing i ask like are we even in the ballpark you know and if not is there a reason to get into is a reason to believe we can um the easiest thing in the world is field testing where we do some uh critical speed or critical power testing and and by that i mean that we send you out um because um rightly or well no i'm not gonna say rightly or wrongly wrongly um people think critical power is something it is not for many years due to a particular training book people thought critical power meant the power you could hold or the speed you could hold for a particular duration so there was a critical power two for your best two minute power and five for your five and so on and that's not the way it is in real life in real life there's

one critical power there's one critical speed and that is the point at which your physiology goes from stable to unstable and the way you figure that out is by doing a few tests at least three so i send you out on your bike and i make you crush it for two minutes i make you crush it for seven minutes i make you crush it for 15 minutes and i do some stuff in excel and i draw a curve and i tell you where that threshold i tell you where that critical power is that critical speed is that threshold that you feel it's about your 10k pace if you're a runner um and that's the most important thing i can tell you to start with because what that does is tell me where you go from a state where you're primarily limited by how much glycogen you got on board how well you're being fed all that kind of stuff what your fatigue resistance is etc to a state where your physiology is fundamentally no longer steady and everything you can think of is treading in a bad direction that's going to result in you getting tired and having to stop probably within 20 minutes the and the way that we've described it in our lab and and i've described it to my athletes is it becomes the anchor of which all of your intensity ranges orbit around yes yes um i think too so the listeners are there's going to be a lot of listeners that are that that think they know what critical power or critical speed is and they're probably in their minds conflating it with lactate threshold power or lactate threshold speed right what's the differences what are the differences between those two well it depends how good an athlete you are okay for the average person lactate threshold so to

define it it's where lactate first begins to rise in your blood we define it as a rise of one one millimole okay so when your little lactate meter goes up by one first time you see that if you started out at 1.5 and now you're at 2.5 you've crossed your lactate threshold and that's important below that speed um or below that power where that that change happened um you're primarily using your slow twitch muscle fibers your muscle fibers that are very endurance oriented they're not very strong but they're they're resilient they can go you can go for a long time on those um your oxygen use is uh is very stable okay it comes up and it levels off and you just carry on okay but once you cross that lactate threshold what's happening now is a bunch of different changes are going on in your body you're burning more sugar you're burning more glycogen from your muscles um and you have a limited amount when you see people who bonk at mile 20 in a marathon this is usually what happened they burn through all their glycogen that they have on board you're recruiting your type 2a muscle fibers these are the faster twitch fibers that you can train enough to make them more enduring endurance oriented or train them harder to make them more sprint oriented um for our purposes here ultra we want to keep them more endurance oriented and then as you go up through that zone what happens is your oxygen use begins to rise disproportionately so it's no longer this nice it rises and flattens out what happens is that it rises and flattens out and then it starts to rise again and that's called the

slow component and so what's happening is that you are becoming less economical with every step you take is costing you more oxygen than expected to do the work that you're doing it'll level out again it may take 30 minutes but it'll level back out okay so things will remain stable it will stabilize eventually and you're okay there until you cross that critical power or that critical speed which is where everything kind of goes off the rails so the idea is that you have these functional discontinuities in your physiology where things take a turn where things change appreciably and it's important for us to us to understand those things if we want to exercise for 10 hours um otherwise we're gonna have a we're gonna have a bad day for sure for sure so you mentioned this testing protocol right you're having somebody go all out for two minutes all out for seven minutes and all out for 15 minutes where those are three time frames and you're having them repeat that test those all out tests three different times and i think this is important for the kind of the listeners to understand there's a specific reason why you have them repeat it three times why is that instead of just doing it once and taking the numbers from there which is what we always like to do no we i mean i i typically do one so in a week i'll test them three times you know one day we'll do the three minute one where they will do the seven minute one day we'll do the 15 minute okay and then i've got a pretty good if i if i look at the model and it looks clean and it's the high r squared and it's very linear um but i'll say okay this is a good model but um you know you can do more testing you can do five tests to try and get get a better uh to

try and develop a better model but it's hard to do um but i'll repeat this testing throughout the season because these numbers move right right as you get fitter they're going to shift and that model gives us two numbers it gives us the critical power which is nice but it gives us something called the w prime on the bike or the d prime when you're running which is like a battery it tells me how much energy you have to spend when you cross that critical power or critical speed you can blow it quick by sprinting or you can ride just above your critical power and burn it out over 20 or 30 minutes but in either case that battery is the same size and it's crucial because once you burn through the battery you you typically end up walking or at least you can't go any faster than critical power so if an athlete were interested in like carrying out and performing this test themselves outside of you know buying your book and following the kind of the instructions that are in there and learning how to fit the curve there like where would they go as a resource to to learn more about that i mean if you google critical power testing um you know you're probably going to find that you can find that many exercise you know physiology a journal at this point everyone's published about it um but it's not it's genuinely not hard to do um so what you do is you do those three tests so let's say i do my two minute test so that's uh 120 seconds and let's say average 300 watts i multiply my 300 watts by 120 seconds and that tells me how many joules of energy i spent

and i do that for the other tests and i plot it in excel on the y-axis i have uh the joules okay on the bottom access right the x-axis i've got seconds and i plot it and i tell excel make me a linear regression there's a little button there right and it does it and it's going to show you the equation okay the number that's next to the x that's your critical power the number that's after the plus sign that's your d prime or your w prime very very high school math oriented right i think you give this really any any high school math student they'll be able to figure that out well and here's the thing you know people have often said to me over the course of my career skiba like you were never any great athlete how is it that you've trained all these world champions as world record holders olympians um honestly a lot of it has to do with having good excel jobs yeah yeah for sure i mean there's a lot that you can do with just the field data or the data that you get out in the field if you're willing to you know harness it as opposed to using the standard uh programs that are out there and kind of make whatever you want to yourself well and just get rid of all the kind of the the hocus pocus and the nonsense right you're doing a training program if it's working you should be getting faster if you are not getting faster the is a problem um and so if you bring it down to that most basic level you can just you can just be honest with yourself and then figure out what you really need to do so so you're using so once again

you're using this test is to determine what the intensity anchor is yeah what's the next step after that are you building the training ranges around that in terms of the the intensity zones yeah so basically you know that for most people who are pretty fit um that the lactate threshold is going to occur at about 70 percent of that of that critical power that critical speed you know um you know if you're talking about since we're talking about runners here um you know ultra running and stuff lactate threshold um is going to be roughly your marathon pace for a well-trained athlete so that'll ballpark it for you um if it's too much different than that then you might not be doing something right yeah um and so really what you're doing is um you're setting up your zones on that basis so below that lactate threshold below that 70 percent that's where all your your long endurance training happens um not that you always stay there but that's where the lion's share of it is is below is down there um in that middle space between the lactate threshold and the critical speed or the critical power that's where kind of your tempo training does you know it is and so um you know i often will prescribe blocks of training there you know so you're doing a two-hour you know two-hour run well on the back half of that run i might have you do a bunch of 800 repeats up in that middle space um critical speed or critical power plus or minus about five percent that's kind of your threshold zone a lot of different kinds of training you can do there and then above that um you know you're

sort of doing your harder interval stuff right that's where you're doing your 400 repeats your it all depends on how fast you are right um but that's where you're doing your real interval work and with the with the athletes that you have the like the opportunity to work with over multiple seasons you mentioned that you know you're kind of coming back to this test how much are you actually changing those training ranges either based off of what you're seeing in the field because in theory if you have really good training data and the athletes are are doing interval work kind of across the entire spectrum over long periods of time you should be getting data points that almost mirror what you would do in this particular in this particular test well yeah well it really depends on um on the way you choose to structure your training so from my perspective i try not to let my athletes empty the tank too often in training um because that in my experience there's a recovery cost there um that that damages your training for following days right which is what we don't want to do um you know the story i always tell people about is joanna zeiger back in 2008 when she won the world championships the half ironman distance and set the world record and that month before that race she was saying to me phil i got another gear now i can feel it you know and i'm saying that's good leave it alone until the race you know don't go there you know there's a time for that it's race day um so i really try to keep rest testing or racing quite

separate from from training um now if somebody totally blows out their their testing numbers in training which occasionally happens um you know someone has a really good day and then all of a sudden you know they're they're you know they're they're long kind of threshold intervals all of a sudden they're putting up 10 or 15 more watts or something out of nowhere okay well that's a sign that we should probably test again or at least we can start training them on the basis of that new data so you're not entirely wrong about that i just try not to do that on purpose yeah this is this has always been my contention with coaches that kind of like overuse power duration curve or pace duration curve to like say whatever you're you're fitter you're more fit in this area you're less fit in this area or whatever it's it's always confounded by effort the athlete can always put out more effort if you instruct them to do so at whatever particular workout and that's going to confound your power duration curve along that particular spectrum so it's like it's self-fulfilling prophecy prophecy in a lot of cases and the other thing that's important is that a lot of what you see in the power duration curve i don't care which product you use um is artifact yeah okay um because there's parts of it that where you were pacing well there's parts of it where you weren't there's there's make this mathematical averaging um that goes on so it's a it's that curve is a ballpark it's not a map yeah um you know okay so you so you already you already you already shifted the tone of my conversation i wanted to talk about physiological testing because that's what i wanted to talk about and you started to go into field work which is totally fine because let's talk about physiological testing yeah yeah i mean but

i mentioned it's totally fine because that's kind of what we have in trail and ultra running because like i said the the tools that we have are very rudimentary but let's back it up let's try to take like you know the perfect somebody's going to come to you and film a documentary and you want to pull out all like the bells and whistles from a metabolic perspective when when you're in that situation what are the tools that you're preferring to what are the tools that are you that you're preferring to use yeah so you test them sport specific so it's a cyclist they're going to ride if they're going to make them run um and you want to make sure that the equipment you're using number one is well calibrated so you ought to be asking that question when was the last time your stuff was serviced you know are we sure this stuff is going to work okay um and and i say that because last a couple years ago i had a world champion athlete show up in my um or a national champion athlete show up in my clinic and and the cart went down the co2 sensor blew um and it was like it was really embarrassing yeah um so so yes you want to make sure that everything is is properly serviced um you know etc um so the first thing we're going to do is a ramp test um we're gonna we're gonna um get them on the bike we're gonna do a 30 watt per minute ramp so they're gonna ride a baseline of about 20 watts for three four minutes make sure everything looks stable and then we crank it up by half a watt every second um and so now you got this power rising and we're gonna watch your vo2 um and we're just gonna keep doing that um you know and

until you get to the point where i'm still cranking up the power but your vo2 doesn't rise anymore we get a plateau in your oxygen use and that's vo2 max right so um that's really testing the limit of what your heart heart and lungs are capable of doing um and so from this data i can now figure out where your lactate threshold is or your gas exchange threshold if i'm not measuring lactate because those two things are the same and we don't need to go down that rabbit hole but um i typically do it from the gas data so i've got that now i know where that first threshold is and i know where your upper limit is your absolute kind of limit in terms of your endurance performance um once i have that data then we can set up a series of tests to figure out your critical power your critical speed right so we'll put you on your ergometer um and uh and we'll set it for some power you know that that's pretty high but still below your vo2 max um and i'm gonna make your ride and i'm gonna make your ride until your cadence drops by five and once your cadence starts to drop the test is over oh that's sure okay yeah i was wondering what the cessation of the test would be yeah and since we're usually collecting gas data too at the same time i can see that you've hit vo2 max and stuff so i know that you've i know that you've really emptied the the tank we do that a couple times and now i know where these different domains are right below lactate threshold below gas exchange threshold that's your quote-unquote moderate domain or your zone two for lack of a better word

and between that lactate threshold or gas exchange threshold and that critical power that's your tempo your zone three okay and then we have that boundary around uh the critical speed or critical power which is zone four and you get five which is that that area above uh above that and so what's the running equivalent of those of the ramp test and the critical speed test so well we'll do a ramp test running yeah um i'll put you on the woodway um same kind of thing because i don't have a mobile meter so we do it we do it on the woodway um we get you running um and we increase by about 0.5 kilometers per hour per minute okay um and so it's a ramp test same thing and we keep cranking it up and cranking it up and then in this one um i give i give the person the option to hit the stop button um because when they when they feel like they're about to collapse so they can whack the button and stop the treadmill um and so and that test works precisely the same uh faster ramp rates tend to work a little bit better than slow ones it helps you get a better fix on where the threshold is um but you have you have it at a constant incline you're just increasing the speed correct yeah okay so yes you set it for like a one percent incline um and that's based on um my former PhD advisor and my good friend andy jones uh that was one of his studies in his PhD was balancing outside the inside and so a one percent incline on the treadmill gets you in the ballpark of wind resistance outdoors so yeah i always love hearing every like all the different protocols that

are used out there we use the olympic training centers protocol which is a two-stage uh one where we're testing threshold and then vo2 max and two kind of distinct tests that are separated by a 10 minute uh 10 10 minute increment but there's you know maybe 20 of these that we can both kind of point to that inevitably if you're in the space for long enough you've got athletes that come in that have gone into one of those labs and then you're trying to compare apples and oranges and bananas and fruit loops or whatever it is yeah i'm gonna use that one i like it no i mean it's true it's true like because everybody wants to know and i would the the honestly the the the the thing that confounds it the most is just the the how many seconds you're using for the rolling average right are you using a 20 second rolling average or a two second rolling average or kind of somewhere in between that that confounds the metabolic data but in the same vein of the field testing where you're using that to set the intensity anchors i get it it's the same philosophy as you're using the metabolic data to to set the intensity anchors of which then you'll kind of carry out in the field yeah and then will you go out and and and have the athlete uh do some sort of field testing to corroborate the numbers or the ranges that you get in the uh in in uh in the laboratory i mean it's typically close enough for government work if they've got a good power meter

um and uh you know and if they're working on the track and stuff like that so it's i don't i don't necessarily do it do it like that um you know people who i test in the lab i try to keep testing them in the lab yeah so i'm like if you really want to do it this way and i give them all the caveats of why it may not be necessary for them um but if they really want to do it that way because look science is fun i like running these tests it's always interesting to be able to test people and see what they got under the hood right um but then i want to keep testing them under the same conditions right and bring them to the lab i know it's the same temperature i know it's the same equipment i know i've calibrated it and so on um so that gives us about kind of a better uh a better yardstick so to speak you just mentioned this so you want to find out what's under the hood and and sometimes we can use either field or lab testing and it helps us direct how like the macro periodization looks and i want to know what your experience is like doing that when you test an athlete and you get a peak underneath the hood and you're like oh we need to do more of this and less of this or more of that and less of this other thing take me through that process in your mind and what things that you're looking for to to help direct that process so that can be more challenging than it looks um because typically speaking things move together it's pretty hard for example to lift critical power without lifting lactate threshold and it's pretty hard to move vo2 max without moving the other two um and so that's the challenge um so so typically what you find is it's

pretty late in the training program or pretty late in somebody's career where you really start having to make those split hairs that finely okay and um you know because because if you look you say you look at elliot right his lactate threshold is because and i go through his data in the book i go through some of paul radcliffe's data in the book um when you look you find out that all those zones all those thresholds are squished together like this you know and it's like now what do i do um but in general um what what i have found um is that early on it's pretty easy to lift everything um later on in the program i tend uh or in the middle part of the program i tend to be focusing on the sort of critical power or the critical speed um since since that's the one that's easiest to measure um and uh and it moves uh and so i can document that movement pretty well um and then once i've got you um and and then you know once i see that creep and drop really close on vo2 max then we can start making some other decisions about that you know um do we want to switch over more if you know um interval heavy protocol or something but again most times like it's the periodization doesn't necessarily fall out of that testing really in a really rigorous sense because by the time we're four or five months in we're getting ready to race and no matter what i think the physiology is going on i have to prepare them to

race so we have to be doing race specific training um if that makes sense well and that was what i wanted to get into next and you described this really well in your pre in your previous books and i've heard you on podcast describe this also it where it kind of almost doesn't matter what type of athlete you're working with in the endurance domain where it's a 10k athlete or triathlete or an ironman athlete or a marathoner if you apply this general rule of organizing your periodization from less specific to most specific you kind of can't go wrong like we tend to we tend to have at least in the past in early in my coaching career this was definitely the case we used to have this strategy where we used to have this notion that these systems kind of built off of each other but as you described it's you move one and you kind of move everything i want you to describe that a little bit better and why that's so powerful though well you know it's it's like this um your physiology is this great big interconnected machine and in the general case it's trying to make the best of what you've got to do what you're trying to do right so let's think about it uh think about this way for a second we know that for most people their most economical cadence on the bike where they use the least oxygen for the amount of power they're producing is around 60 rpm ish right right right but nobody races exactly

because my goal is not to have the most economical performance it's not the fastest performance right and so your body ends up optimizing cadence of you know on the basis of the power you need to make um your physiology works kind of in a similar way where it's making the adaptations to try to do what you're trying to do and now um do we need to have smart from time to time yeah probably okay one good example of this is when you're doing really long endurance training for long endurance ultra events for example um it's uh you know when you're down in that lowest zone that zone two below that lactate threshold you're primarily stressing this type two the type one muscle fibers right the endurance oriented fibers if you start going a little too hard you're going to start recruiting more of those type 2a fibers right i don't have strict evidence for this but i believe that as you recruit those fibers you might be taking some of the work away from those lower order fibers that you're trying to maximally stress for endurance purposes um so and so you know do i sometimes throw in those blocks of heavier work during a really long endurance workout a five hour ride or something sure i do i typically try to load those towards the back end of the ride when the athlete is

capable of it because what i'm now doing is you know training them to be on the tired legs and have to recruit those higher order fibers for when it's necessary um so so you can do crafty things like that and and but other guys have figured it out on a very non-scientific way right you look at the kenyans like those guys you and i can run with them if we're in decent shape when they start out because they're running 8 30 pace or nine minute pace when they start the kenyan shuffle but by mile 10 they're running 6 30 pace and by mile 15 they're running five minute pace and so on um so they're they're back loading that heavier work too yeah and i've heard um that rationale uh explained for progression runs and things like that in the past and i i get it i mean i can kind of understand the physiology behind it my contention is has always been though it always limits the total amount of work that you could do for whatever you're asking the athlete to do so if you're asking them to do like just say 10 minutes right just to make make an equivalent i want you to do a 10 minute hard block at the end versus the beginning you're always going to get more kilojoules of work if you do that 10 minutes of hard stuff at the beginning versus at the end and so it's like it's not a robin peter to pay paul but you have to understand that you're eliciting different physiology which i guess is to your point right you're trying to hack into the physiology that you want to optimize yeah yeah precisely um and this is

interesting about this right um you know we're we're trying to you know like my buddy dave clark says uh you know he coined the term performance engineering right and that's what i think of us doing like you know like a lot of the hand holding and like the talking and stuff that's the coaching that's kind of the the art um but there is this part of it there's very much this engineering approach to you know let's try it this way let's measure the results like that didn't work okay let's try something different um and that's just something very gratifying about that you know 100 percent um you know i want to give you a little bit of an opportunity to describe what else is in the book um but when we were off air um and for the kind of for the listeners out there this this is not phil's first rodeo at writing a book and i can appreciate his his story i've i've probably bought i'm going to ballpark it at 40 between the the the first i can't it's like edition one or edition two or or volume one or volume one book there was the physiology book the blue book training for triathletes and there was the green book that triathletes got in with power okay so anyway between between those two i've probably bought 40 of them for our incoming coaches kind of over the years yeah i mean it's a good yeah well it's i mean no thank you because i'm i'm not set up to be a freaking physiology textbook you know and a lot of times i need to you know we bring in coaches that are at all different stages of their educational levels and

at a certain point we have to like level that that field so that we can all kind of communicate with each other and that's and i guess my point with that is is this is a resource or those were resources that i would constantly go to to get everybody on the reading from the same book and from the same page yeah absolutely but with the new one coming out when you were writing it what were there one or two like really remarkable things where you were just like i wish if everybody understood this it would make athletes and coaches a whole heck of a lot better yeah i i mean for me uh uh understanding intensity and and these domains and that they have physiological um this there's a there's a discontinuity in physiology where something appreciably changes in the way the body works um that they really understood that that's a real phenomena that it's not about just going as hard as you want or constructing a workout to be a certain to look a certain way it's that the body starts to work in a fundamentally different way at these different points and you got to respect that if you want to have the optimal you know you want to optimally train somebody um and so for me that was and that's why i took such care in writing that portion of um and understanding that connection between the physiology the power duration curve and what you observe what the athlete feels um

and and when you tie those things together it's really powerful um in terms of the level of understanding and the way you can explain things to athletes help them understand what they're doing to get more buy-in um but to just to write physiologically appropriate workouts well and that's what i look that's the lens that i look at it through it's getting the right dose because you can always prescribe intensity and maybe get lucky that you're kind of doing it doing it for a long enough duration or enough kilojoules of work or enough miles however you want to describe the duration part of it or the the volume part of it but if you really understand the physiology behind each one of those intensities it makes it that much more powerful because everything is is dose dependent and if you don't get the the the the the the volume component of that dosing right it's just like in medicine where you're not getting the you know the amount of milligrams of whatever kind of prescription correct either yeah and if you if you because i have a whole the whole chapter there on impulse response models and dose response modeling to really drive that idea home that it works like a dose of medicine yeah and i can give you two aspirin and fix your headache i can give you three and i can fix your hangover or i can give you 50 and wreck your kidneys you know and and that there is this like this predictable relationship between dose and response or you can give a quarter and not do anything it's the same with training no seriously i mean how many how many athletes especially really good athletes underdose

their training it and when they do it it's normally for they don't have enough volume at a particular intensity right they get the intensity correct they're trying to do a vo2 max interval or whatever but they don't have enough volume at that particular intensity to elicit the response is usually where it goes haywire in my observation of of training programs and a lot of that has to do with the kind of people that you're seeing right a lot of people end up to me coming to me because they got hurt or they got sick or something else and so i often see the other side of the spectrum yeah the people that overloaded on something and then ended up going over over going over the edge and doing something bad yeah um so so yeah it's interesting but yeah but it's about figuring it out where's that optimum how am i going to do that but it's is it fair to say i don't want to like paint you in a corner with this is it fair to say that you're typically not ascribing to what most people would refer to a polarized way of intensity distribution where you're using intensity distribution that kind of leverages the whole set of the intensity spectrum from very low intensities to very high intensities and then you're just modulating the dose in between versus what people would think is what people typically think is polarized which might not be entirely true which is either everything is really easy or really hard and then nothing or very little in the middle yeah and you see people who do that um but but they're very often not very good um part of the problem with ascribing to this thought process right is that you are

taking a paradigm of training and you're trying to fit an athlete into it and that's the opposite of what you ought to be doing right you need to change your training paradigm to fit the athlete now if i am training a world-class 3k or a 5k guy guess what a relatively polarized model can be extremely appropriate depending on where you're training them right but if i'm training an iron man triathlete you know or a marathon runner or something um you know one of the things i do in the book is i break down you know uh elliott's and paul is training and you would be hard pressed to call those training programs polarized um because they're doing a lot of everything and a lot of it's very hard a lot of it's very intense um so i just you know the thing is like i think part of this is just people need a thing right i'm the i'm the polarized guy right you know i'm the threshold guy right everyone needs a shtick yeah it's true and it's like i'm like i'm very pragmatic i'm the what works guy yeah i'm with you on that i've been in coaching a lot long enough where i've seen all these things come around right first threshold hit trainings all in vogue and then it's vo2 max training and then it's polarized training and then it's like something else the diets are the same way right 20 years ago it was all atkins high protein now all of a sudden we're gonna call it keto but it's gonna be the same i'm not gonna say what i want to say yeah no i gotcha same thing different shovel but i think i

think from an athlete once again i think the athletes that are listening to this i think the the the practical take-home point is is is something that i've tried to drive home a lot is is there's room in there for all different types of intensities we don't have to prescribe to one particular thing it's just a matter of how much are you leveraging those intensities to what extent throughout the year that really is where the sauce is made correct and how much time do you have to train right like doing a tremendous amount of kind of zone three training um to the exclusion of everything else might not make a lot of sense unless you're a guy who's only got four hours a week to train then it might make more sense you know and i think that's that's the thing is how much time do you have to work with what are your goals and how close to an optimal program can we then develop yeah okay before i let you go i think it's an important point for athletes to take home uh some of your viewpoints on supplementation because i know you see this as a as a medical doctor in addition to being able to combine it with kind of your coaching knowledge and i know it seems somewhat out of left field but um i think in today's sporting culture in today's age of trying to find really quick fixes for things we can we should take every opportunity that we can to really drive home some some key message points here so i want to hear your view on on supplementation and what the athletes can really take away from that yeah so so that's that's a great point and i discuss i have a whole chapter in

the book about nutrition and supplements and you know i'll refer you to ron mahn who is one of the best physiologists ever right and and a really good guy to have a beer with you if you've ever had the opportunity who will tell you that if it works it's probably illegal or at least um uh or at least uh not allowed in sport um and uh and there's lots and lots of stuff out there that doesn't work at all um so there's a few things that we know work reliably we know caffeine works we know nitrate works in the form of beet juice or spinach you know smoothie or whatever you want to use um if you're making your own juices to get nitrates make sure you're buying the cheap vegetables that are grown in the high nitrate fertilizers don't buy the stuff from organic farms it doesn't have enough nitrate in it typically um and uh you know we know that uh heat acclimation going to altitude we know those kind of things work um but in the general case there are not a lot of things you can put in your body legally um that are going to improve your performance um believe me if there were i would know about it um but the greater risk is this um there are lots and lots and lots of contaminants and supplements um over the course of my career i cannot tell you how many kids i had show up in my clinic with funny liver function tests and you know um and and the doctors didn't really know why

um well funny liver function tests are a symptom of oral steroid use and this kid's jacked you know he's 15 years old and he looks like a linebacker for you know or a professional wrestler or something and i'm like you know using steroids and they're swearing up and down that they're not and then we check their supplements and turns out one of them's you know loaded with steroids um because it came out of some some lab in mexico or china or something um so if you're taking these kind of supplements you're taking things like creatine if you're doing and all of a sudden they really seem to work like work really well there's probably a bad reason for that um and you probably shouldn't be using it so um you know there's no free lunch so like i said you know optimize your carbohydrates get 120 grams in per hour of exercise if you can tolerate that much if your guts don't get upset use a little bit of caffeine use nitrate but otherwise you're wasting your time and your money phil to that point i'm going to leave a link in the show notes to a recent paper that came out it's titled dietary supplements as a source for unintentional dopings came out like just a couple weeks ago i think uh where they analyzed i think it was over 3000 different supplements and found that 28 of them had something unintended uh in them it's just a it's it's a really big issue in high performance sport um and it's going to continue to be the case just because of how unregulated

how unregulated it is so i really appreciate your thoughts on that um i'm going to leave links in the show notes to the book i hope everybody goes and check it checks it out but is there anything else you want to leave the listeners with in terms of how to get a hold of you or how to get a hold of the book um yeah i mean you can find the book on amazon unless you're abroad or in europe or around the world you can find it just on my website there we'll ship it to you um but uh you can find me on twitter drop me an email uh you know i i try to answer as many of those emails as i can i think part of part of what i'm supposed to be doing in life is a little bit of outreach um because you know my my goal i've often said this in podcasts my goal as a as a coach has been to put myself out of a job as a doctor right i want you to not get hurt i want you to not get sick i want you to not do something silly um and if i can help you do that i certainly will um but but i appreciate you talking to me today jason this was a lot of fun that's an awesome way to wrap it up phil thank you for coming on the podcast i hope you i hope to bring you back on the next time you publish another book which is hopefully sooner than five years from now or seven years from now thanks for coming on the show thanks for having me buddy all right folks there you have it there you go much thanks to dr phil always weird kind of calling him dr phil dr phil coach phil for coming on the podcast today i hope that was insightful for all the athletes out there seriously y'all i'm gonna leave a link in the show notes to uh philps skiba's new book scientific training for endurance athletes go and check that

out it is a must-have for all endurance coaches and all endurance athletes i cannot recommend it highly enough and if i were to place a bet in vegas i would say that over the course of the next part of my coaching career i'm probably going to buy about 50 of these for my athletes so maybe i'll just buy them in bulk right now or for my coaches and maybe i'll just buy them in bulk right now it really is a fantastic resource kudos to phil for getting it back out there i appreciate the heck out of each and every one of the listeners if you like this podcast please share it with your friends and your training partners i love seeing y'all out in the field and how impactful that the content contained within these podcasts has been to inform you guys of your all of your training and ultra adventures that is it for today folks as always we will see you out on the trails you