Research Breakdown! Interval frequency with CTS Coach Corrine Malcolm | Koopcast Episode 50

trail and ultra runners what is going on welcome to another episode of the KoopCast as always i'm your host coach Jason Koop and on this episode of the podcast i have a repeat offender and cts coach corinne malcolm corinne is fresh off her recent fkt of the tahoe rim trail which she finished in a blazing 44 hours and 53 minutes for the 171 mile route that circumnavigates lake tahoe so congratulations are definitely in order corinne nice job out there it's a huge route and a heck of an effort we actually recorded this podcast well before she even knew if she's going to get another crack at doing the route and thus there's not even a mention of it during the course of our conversation as many of you know corinne is not only a great athlete as her fkt demonstrates but a spectacular coach with a keen sense of sports science so i wanted to bring corinne on the show today to break down a recent piece of research that i found just fascinating this research pitted two different frequencies of interval training programs against one another to determine which one is superior for adaptation yeah that sounds like a mouthful and let's face it research is oftentimes boring and tedious and can even seem like it's written in a foreign language not to worry though coach corinne and i do the heavy lifting for you and we break down the entire thing in this podcast

so it's understandable relevant and applicable to your training so here we go let's get right into it here's my discussion with coach corinne malcolm let's get into it so we're gonna we're gonna bring this paper down that's from the international journal of environmental research and public health which is a really weird journal for like sports performance to come from but it's neither here nor there the title of the article is the influence of interval training frequency on time trial performance in elite endurance athletes and it's out of this group from norway uh it's out of bent rodsted's lab and there's a lot of norwegian names in here that i'm sure i'm gonna mispronounce so i'm gonna try to do the best i can the lead author is epston tonston and the secondary author is johnny hisdell um but this lab i think relevant to the listeners out there this lab is kind of notorious for two two things that are relative to this conversation the first thing is they study a lot of cross-country skiers being in norway they've got that's their pool of athletes they have to work with it makes all the sense in the world and the second thing is they're really notorious for studying high intensity interval training and all of the different combinations and concoctions that that high intensity interval training can can contain there's so much high intensity interval training like research coming out of

this group and out of norway in general it's kind of hard to keep track of it yeah it's they're they're what do we say they're they're prolific prolific yeah prolific prolific and they study it all they study like 30 second intervals three minute intervals medium length intervals long intervals and on and on and on and on but i think that the salient point there is they they are very well versed in designing training interventions and designing studies to evaluate training interventions that can look at different types of high intensity interval protocols and are they effective in what they are supposed to do so this study specifically what they wanted to do is they wanted to look at as the as the title of the article uh alludes to they wanted to look at the frequency of training training in an iso work setting meaning the same amount of work is done across two groups of athletes and see if that frequency actually makes a difference and so the way that they did this is they got a group of cross-country skiers of course because there's tens of thousands of them in norway that they can find i mean there's got to be a lot of is that number even remotely correct corinne you're you know more about this than i do oh i don't know what the exact number would be but yeah they've got a lot cross-country skiers and a lot of um bi athletes and this is pulling out of their like junior and u23 kind of elite pool yeah so they found 20 of them heavily dominated on the male side there were two

there were one women and there's one woman in each group divided them into two groups one of the groups they called the low frequency group the other one they called the high frequency group and they did the exact same amount of training over a 12 week period save for one small wrinkle the majority of the in that one small wrinkle is the majority of the interval work so the majority of the interval work is what they're trying to test and they essentially arranged it to where one group the low frequency group did two workouts per week and then the high frequency group did the exact same amount of work but they just spread it out over four workouts per week and the at the end of the 12 weeks they measured their uh an eight kilometer roller ski time trial their vo2 max and their uh their vo2 at their is either their aerobic threshold their anaerobic threshold anyway essentially essentially economy is what they're measuring and in the high frequency group so the group that had four workouts per week there was no change across any of those in the low frequency group they improved their time trial performance and their exercise economy but not their vo2 max which kind of makes sense because they're really good athletes to start out with like 67 vo2 max so that's the overview we've got these two distinct groups a low frequency group and a high frequency group that do the exact same amount of training

at the exact same intensity over the course of 12 weeks and the only wrinkle in it is they just work the the workouts for the lower frequency group were generally longer like the interval sessions contained more volume of intensity and in the higher frequency group they did a shorter volume of intensity but the same volume of intensity over 12 weeks so that's the overview corinne what do you like what do you take from this so i think the biggest thing and we're definitely i feel like going to dive into this when you have the high frequency versus low frequency group the you have to think of like week to week training construction right and so when you only have one group doing when you've got one group doing four sessions a week right there's seven days in a week so all of a sudden more than half your days a week are going to have intensity on them the low intensity or low intensity low frequency group with only two sessions a week seems more indicative to what common practices and what you and i would see in a normal like running training week for example so there's a lot of familiarity there so they're trying to look at like all of a sudden with four workouts like you got a back-to-back day of heart intensity it's that's really hard to do and they do mention that um there was some deviation periodically where an athlete might have needed to take a day off of training because they were too tired yeah um and also the group that had the four training sessions or four high intensity

sessions a week they also had a little bit more attrition as well attrition being three of the three four of them did not complete the study um one being an accident that didn't have anything to do with the study and three um dropping out for various reasons so hard it seems like it was harder to maintain over 12 weeks as well yeah let's back up a little bit because i think we need to kind of just kind of describe what the workouts look like and if anything this is a really boring training program like in both groups it's super boring so they did the intervals the exact same intervals and once again this is research so they're trying to test one variable at a time and try to limit the amount of things that are going on and so the intensity that they were testing at or the intensity that they were that the athletes and the researchers were primarily focused on is what what a lot of people will call zone three so in a typical five zone heart rate based training program and they were using heart rate to monitor their intensity zone lactates it and blood lactates yes so zone three would be just below or at a typical person's lactate threshold and to to contextualize that a little bit more if people aren't like that familiar with it it's a it's the intensity that you could sustain for about an hour if you were killing yourself maybe these elite athletes could do like 80 minutes or 90 minutes if they were just

killing themselves so it's not high high intensity but it's not obviously low intensity so all of the sessions were at the zone three intensity and for the low frequency group they had two workouts that they alternated eight by eight minutes hard at that zone three intensity with two minutes recovery and six by 12 minutes hard with is that two with two minutes recovery as well in three minutes recovery yeah 20 to 30 recovery time yep so they alternated those two workouts and in the high frequency group they basically took that interval interval design and chopped it in half so their two workouts they did all the time for 12 for 12 weeks in a row it's a long time to do just two workouts was four by eight at zone three with two minutes recovery and three by 12 in zone three with two minutes recovery so once again it's the exact same time and intensity between both of the groups it's just the low frequency group has double the amount of time in one particular session versus the high frequency group yeah so two long workouts versus four shorter workouts but the same accumulative time every week over 12 weeks yeah so six by 12 with three minutes recovery or eight by eight with two minutes recovery at that intensity that's really hard like that's about the most amount of time at that intensity that i would ever give an elite athlete i don't think a normal i don't i

could not handle that me personally i'm a i'm a decent athlete i'm not a great athlete but personally i would have a really hard time handling six by 12 minutes which is 70 minutes of intense 72 minutes of intensity my math is not very good this morning 72 minutes of intensity um at at or close to your lactate threshold in one session having to repeat that at least once a week every week that's the picture i'm trying to paint is that's a really freaking hard workout yes i would also i'm nodding my head no one can see this um i would also say so there's some nuance here to ski training that can be a little bit missed sometimes when we're looking at it from a running lens and so oftentimes even i had coaches who wouldn't even say they'd say out of four zones and they divide l3 into two like low l3 versus high l3 and so sometimes these l3 i really like these l3 workouts because they're almost they're generally targeted just under lactate threshold um which might be more akin to people who are used to kind of our rpe zones more like an rpe 7 7.5 than like a true rpe 8 out of 10 so it's still a very hard workout but it's a little bit different than how we would traditionally look at lactate threshold intervals with runners yeah it's a little bit lower intensity it's super nuanced though yeah i i agree it's super nuanced but at the end of the day those are both two really hard workouts and if you compare that to

a high frequency group and once again this is the group that's doing four interval sessions per week they're doing four by eight with two minutes of recovery and three by 12 with two minutes with three minutes of recovery still a hard workout but not not nearly as much volume of intensity as in one single session as the low frequency group true but all of a sudden they the low frequency group has more days of recovery between those two harder workouts so once again that's like a dosage density of training question that i know that you've been thinking about a lot recently yeah it's it's interesting the authors made this uh really uh poignant remark kind of at the end of the abstract that caught my attention because one of the words was in was in quotation marks like they were they didn't want to use the word but they're using in any way and they realized it might have gotten rejected because it's really not that scientific so they wanted to put air or they wanted to put like physical quotes around it so so it kind of like passed the scientific test but i'm i'm going to read it because i thought it was interesting the longer time between training sessions and the low frequency group may have also allowed athletes to recover more effectively and better in quotes absorb the training these findings are in line with the in quotes best practice observed by many of the world's endurance athletes and so when you think about it from a research design standpoint they're saying okay

the way that we're arranging the low frequency group is the way that we would normally do it right that's the way that's the quote-unquote best practice what if we just halved all those sessions and let's say there's an advantage to that let's say there's an advantage to the susceptibility to injury that one might sustain in doing this huge volume of zone three intensity in one session if the outcomes of the low frequency group and the high frequency group are the same you could theoretically say okay we need to do more of this high frequency type of training because the the the advantages is otherwise specified particularly with injury risk or whatever might be more advantageous but that's in fact not what they found they found that these best practices are kind of there for a reason almost yeah and that's extra i think that's extra curious because so this was done once again with skiers and they also make it very clear that this intensity was also done skate roller skiing so not not classic versus skate not running versus skiing versus biking they also made sure that that was held constant and every single one of these sessions was done on skate roller skis which biomechanically from like a stress a structural stress standpoint is going to be very different than if we had a runner go out and do six by 12 minutes yeah and they're using heart rate to essentially get everybody into the into the right intensity um and this the heart rate of the of this zone three intensity was right

around let's see what it was at 82 percent 82 percent of max heart rate help me out with this one i think they said oh yeah here we go 82 to 82 to 87 percent was kind of their tar their target for any of these 82 sorry 82 to 87 percent of max heart rate was the target for any of the interval sessions so once again it's hard but it's not like lung burning leg screaming type of heart it's kind of a sustainable intensity and i've always viewed this type of intensity in particular i think i think that most endurance and most endurance intensities that we train at kind of hold the same theme but this this research or this piece of research really accentuates this where volume is the critical piece of overload and you have to have a certain amount of exposure at a particular intensity in order to create that overload which then the athlete can't adapt from and clearly from the results of this the higher frequency group who have about 32 to 36 minutes of exposure at that zone three intensity albeit four times a week but only 32 to 36 minutes in one particular session that was not enough training stress to create to elicit an adaptation because they had enough time to do it they did it

for 12 weeks yeah and so it's is it a combination of like obviously and we've talked about that with at different intensities they're required load to make the like dose essentially to make a physiological adaptation like we've stressed the importance of that when it comes to interval math but at the same time too it brings us back to this idea that they kind of tried to allude to in that and like the last sentence of that abstract of is it volume is it the volume of that um one session or two sessions a week um or is it their ability to actually adapt to the stress of the workout um given that they have more recovery or more easy days in between like i think that's i don't think they were able to tease that out necessarily in this and is it worth teasing out i don't know but that is kind of an interesting leftover artifact of this study is that you know they know that it worked better in the low frequency group that is apparent in both testing you know in the testing post post 12 weeks that is very apparent but did it work because those sessions were big enough or did it work because they weren't toasted trying to do four sessions a week yeah but the other thing with that is like even if you wanted to use a high frequency protocol or not a high frequency protocol if you wanted to reduce the time of intensity right to let's say okay let's just make the math easy because my brain is apparently not working this

morning let's just say you know an athlete can handle 60 minutes of this zone three intensity in any one particular session you just know they can do that let's just say you wanted to reduce that for whatever reason and keep this low frequency style just do it to two days per week and you're going to reduce it to 50 minutes that seems pretty trivial right just by 10 minutes per week or whatever you want to make it more sustainable in order to do the same amount of work at that intensity in the contrived situation in the 50 minute situation you're going to have to do your training protocol is going to have to be longer so instead of 12 weeks it's going to have to be 13 weeks or something like that so that that's the counter argument that i would say to well you can just reduce it and you don't know if it's the if you don't know if it's the quote-unquote absorption time frame because you already have the time frame set out that it's 12 weeks yeah i mean that's that's true that is part of the interval math i guess it's an efficiency thing i guess it's an efficiency thing right um i one of the things that i think is worth pointing out is the fact that these are elite athletes these are really good athletes and training intervention studies are very good at pointing out what works good what works better and what works best with elite athletes because they they have to they require so they require such precise training in order to improve now that's

not to say you have to go and chase marginal gains or anything like that but particularly with training architecture they won't improve if the if the training architecture isn't very good is this study his his really eloquently kind of put out when we translate this to normal people right there still is a good better best so i'm going to give you my guess no actually we'll do your guess first corinne then i'll go my guess so with if we just took this same this exact same protocol right low frequency group high frequency group but instead of these badass cross-country skiers and biathletes that they had for this for this training session and we just did it with some normal people like your average athletes corinne how do you think do you think the results would be any different no but i think attrition might be higher because the workouts are so hard yeah like they would probably be better suited to us stepping down like the total duration slightly like instead of 72 minutes maybe you're aiming for more of those 60 minutes over two sessions or 60 minute sessions um and making the study longer but in the in the confines of a 12 week study like doing the exact same thing i think that you know in theory the low frequency group should still do better but i think attrition is going to be super high okay let's let's normalize it to let's let's make it to a normal person so one of the we know one of the big differences between elite athletes and regular athletes is the elite athletes can

handle a larger volume of the same relative intensity no matter how you describe that relative intensity lactate threshold a percentage of vo2 max whatever if you know we take elliott kipchoge and we take me and we're running at the exact same relative intensity 80 of our vo2 max 90 of our vo2 max threshold however you want to do it elliott's going to be able to run for a longer period of time than i am way longer so for sure for sure for sure now so so what you're saying is is one of the things if we wanted to make this relative to to all athletes not just elite athletes one of the things we would have to do is scale down the volume of intensity across each of those groups so let's say we did that let's say we scale it down to like 75 percent right six by 10 instead of six by 12 right for the for the high frequency group and three by eight versus four by eight for the higher frequency group let's say we made those appropriate scale downs we repeated the experiment with your athletes corinne you're you know every day weekend warrior types of athletes what do you think the results would be then i still think the low frequency group so okay so let's take another another important factor with these athletes these are all average age is 22 for these athletes correct so aside from them being elite they're also young right and that is important because what we know is that as we age we need more recovery in between interval sessions

to to reap the benefits of them like that is just a fact of getting older um and so and with that in mind i still think that low frequency for the general population of our endurance athletes unless they're you know in their 20s or maybe in their young 30s and super fit a low frequency but but longer session is probably going to be better because they're getting more recovery in between those sessions and so they're probably getting higher quality work done in those two sessions versus lower quality work over four sessions a week that's a that's a hard week for anyone yeah i don't know if i would describe it as lower quality it's just a less volume of intensity right i guess you could you could describe it on day four if you're really tired yeah well in the real world that actually might happen right once again these athletes are able to sustain the protocol because they're good if you have an athlete that's not as good you're right they actually might fade off in the 10th or 11th or 12th week because they've had so so much volume of intensity my guess is is that if we scale this down for everyday runners my you know my normal runners that i kind of work with put it to like 75 percent of the volume of intensity so it's like 45 minutes volume of intensity for the low frequency group and like 25 to 30 minutes of volume of intensity for the high frequency group i would think that both groups would improve but the low frequency group would improve more and that's just because it's still close to enough in the high frequency group it's still close to enough exposure at that intensity that a lot of a

lot of athletes not everybody but a lot of athletes will get some sort of adaptation it is close though like if i see so the the zone three is pretty analogous to our tempo run right that's the vocabulary that we would use and you've seen me do this karen in our coaching sessions if i see a tempo run session that's like 25 minutes i'm gonna say that's not enough time and intensity fact how many times have i said that over the last two years a lot four years it's a lot a lot um so i would i would look at it through that lens first even though you might be doing it in back-to-back fashions it's still enough still not enough single session exposure i just made that word up single session exposure it's listed an adaptation trademark it right now i will i will um this this this group has put out a lot of really cool research that's that's like corollary to this where we look at something and we take the exact same amount of work and we just do it a little bit differently we concentrate it a little bit more the sessions are a little bit longer sometimes they're rearranged differently they've kind of got a good pattern for b for being able to do this and they produced a a paper that i'll link to um in the show notes that i actually just um i just revisited this morning and i've written a couple of articles on it as well the title of it is block periodization of high intensity aerobic intervals provides a superior

provide superior training effects in trained cyclists and the protocol there was actually the the vein of it was very similar to this one where they took the exact same amount of work with two groups of endurance athletes and this time it was cyclists it's just easier to control cycling studies as opposed to running studies and and they rearranged that workload and they tested okay which one's better and the way they did this one was really lopsided so they used a four-week intervention which is pretty short admittedly and in the blocked training group which is what they were testing they did five high intensity interval sessions in the first week which you would never prescribe for anybody who's not trying to win the olympics like that's a really hard protocol for anybody i've seen i've seen this done we would frequently do like a week or two of this and it's not fun it's hard it's super hard so five high intensity really hard sessions in the first week one in the second week one in the third week and one in the fourth week so there's eight my math is correct there five plus one plus one plus one is eight so there's eight high intensity sessions over that four-week period in the other group the peanut butter spread those high intensity workouts out to the first week to the second week to the third week and to the fourth week and then they tested the groups at the end so very very similar the exact same amount of work over the same period of time four weeks

and they're testing and they're testing them at the end turns out the blocked style produced superior adaptations to it now in with your comment coran you could you could come at that one of two ways you could say okay it's the concentration of training that elicits the adaptation those five that are really freaking hard on that first week or it's they were able to in quotes absorb the training because weeks two three and four only contained one workout that they were just more primed to do a vo2 max test to do some sort of time trial at the end of that intervention and i'm i don't have the paper on my computer off the top of my head but i definitely know that there have been studies done looking at ways to elicit bumps in vo2 max and they're set up very like specifically for that reason and they're set up super similarly where you're doing five sessions like that over nine days for example and i do know a lot of skiers have done similar protocols and that the goal of it is to basically just elicit this like weird fitness bump but if we look at no but if we look at training like from that standpoint that only works in a very short well one with like very like very highly trained athletes one two like that's nothing that you can do chronically this is like a very acute training camp situation where there is adequate recovery on the tail like on the back end of this and so it's not a chronic situation so that's an interesting study over four weeks where you're right in quotes like could they absorb the training better because they survived week one and

they got to recover for three weeks yeah it's um and i think it kind of a note of caution before anybody out there listening decides to do five high intensity interval sessions over the first week once again one of the one of the reasons that um that these researchers use cross-country skiers and cyclists in these studies is first off coming out of norway they just have access to a lot of cross-country skiers and then the second thing on the on the kind of on the cycling side of things it's just easier to control the intensity because you can put them on an ergometer they're not out in the real world you can measure their power output and all that stuff just lends to more valid and accurate research but the the third piece which is important for the runners out there is that there is absolutely an orthopedic or a musculoskeletal consideration when we're stacking these types of workouts up that does not exist in sports that are not as weight bearing or not weight bearing in the cycling side of things so before anybody kind of translates these of these and says okay i'm gonna go do six by 12 minutes hard three three minutes easy and then back it up with eight by eight eight by eight is really hard just because it's eight intervals now that i'm thinking about it um i think i think like take like take a step back and just realize that there might be some mode specific uh adjustments to the training design yeah training level age specificity of work type

like those three things like that that's the thing with any study right it's really important when they say oh this was statistically significant that like we saw this or whatnot in the in the study yes but that normally isn't specific to a general population it is specific to the people that were used in the study and that's true of any study unless it's a big study that's on the general population but from an exercise science standpoint that's very rare it's normally very small like the end of this was ended up they started with 22 but the final end was like 15 yeah they had a lot well they well so in the so in the first study that we're talking about the one that was studying uh training frequency where they just reduced the time and intensity that we spent the majority of time at they actually ended up with really small groups at the end because of what you're alluding to karen uh some of the people dropped out for for for various reasons and that's a weakness of the study that the authors point out so there were six people in the high frequency group at the end of the study and there were nine people at the end of the um uh at the end of the day in the low frequency group not something that you would like throw the baby out of the with the bath water because of those low numbers because that's not that atypical for a training intervention study to have those types of numbers but i think when you look at this particular study in the context of everything else that's coming out the the conclusions like the ultimate conclusions that i draw are kind of twofold it's one if you take

the same amount of work and concentrate it you're probably going to get better adaptations on in any kind of group of athletes the second one is is as the athletes get better there absolutely needs to be more importance played to this minimum dose of intensity that is needed to elicit an adaptation on any one single session and it's kind of the way that our workouts are designed reflect a lot of that a lot of that workout so for a running interval workout which is like vo2 max type of intensity we try to get 12 minutes the time of intensity at the very minimum for tempo work or zone two work we try to get like 35 minutes time at intensity more if they're an elite athlete but for a normal athlete 35 minutes if you're doing less than that you're probably just spinning your wheels but those two facets the concentration facet or the density facet and the minimum time of exposure at the intensity that's needed those are kind of the two critical takeaways that i'm that i'm drawing from this and kind of all the surrounding research in in the orbit yeah i would say that's an accurate summary of this study and i would say that um i like that they pointed this out as well is that they wanted to impart their testing like this is what we see athletes do is there a reason why it's effective right um which i appreciate about a lot of sports science research is that oftentimes it's like we see these athletes being successful doing it this way

can we like backtrack and like make sure that the physiological um adaptations or whatever we think you know is the the like steps of that make sense from a science standpoint so it seems a little bit reverse compared to other fields but i think that it's um pretty common in sports science and i like that they like play or they like acknowledge that in this study as well yeah well i mean training training structure always evolves more quickly than the research can keep up with it because it's easy right i can decide tomorrow that i want to go and do 10 times the incline right whatever convoluted thing that i think is efficacious right i could do that tomorrow but to study 10 times the incline but that might take two or three years if somebody wants to study the efficacy of that one particular training intervention so athletes are always going to move faster than the researchers and a lot of times you're right it's validating what you know what the athletes have done for years i got in a lot of trouble for saying that to my graduate advisor oh yeah oh yeah no i said that i think that science oftentimes lags behind sport because it's just as you said athletes or athletes and or coaches are making these kind of educated guesses that pay off oftentimes and then the science is done later to kind of back it up or to understand why it works and my graduate advisor at the time was super offended by that statement and i got

reamed out over it but i think there's a lot of validity in that statement and i think just as you point out that's what's happening here that's what's happening if we were to make an educated guess to guess about something you know down the road same sort of thing well whenever you whenever you challenge somebody's like tribe or way of thinking they're going to get a little bit irritated you could say the same thing about research right when a piece of research comes out that flies in the face of what an athlete or a coach has believed for years a lot a lot of times there's a lot of resistance behind it and they try to poke holes in the study so for example if i thought for whatever reason my bias was uh well if we peanut butter spread these zone three workouts more like we did in the high frequency group if i thought and i coached my athletes for years that that was a superior way of doing it i would look at this study and go okay there's not enough people in there it's just focused on elite athletes the training intervention was only 12 weeks you need a six month training intervention and things like that like i would come up with all the holes to poke in the and there are holes in no research is perfect right no research is perfect i would come up with all the ways to poke holes in this particular paper to validate my my my point of view and we see that with you know your professor trying to you're trying to validate the fact that the athletes can move faster than the research it's the exact same thing it happens in nutrition a lot but let's not talk about that because that'll be a total rabbit hole yeah like back it up back we're not going that direction okay so we're not going

to go that direction let's try to sum it up and come up with like the really practical salient points for the athlete corinne you can choose if you want to go first or you want me to go first i'll go first ladies first all right ladies first i love it we'll say age before beauty oh um thank you very much so i uh it's a podcast no one can see us i don't know um so summary we've kind of summed this up already what this study says in elite athletes but can be taken i think as we've both discussed to the general population of endurance athletes is that you are going to get more bang for your buck training by doing what the low frequency group did by doing two quality interval sessions a week as opposed to four um that have higher dose of intensity that there's a minimum dose required to elicit adaptation and so at this intensity we've discussed it's at least 35 minutes or more going lower than that even if you're getting the same amount of intensity as someone else throughout the week just spread out more you're not going to get the same same results so i think that's the biggest takeaway here is that dose is important minimum dose is important and even um for our general athletes not elite athletes um that is that is still important um for them to take into consideration i'll back that up so but my biggest my biggest thing is is yeah i i agree with when you concentrate the same amount of load over the same amount of time onto one or two days per week you're typically going to get a bigger

adaptation but honestly my bigger my bigger thing is is just what you mentioned earlier is there's absolutely a minimum amount of time and intensity that you need to spend depending upon what you do what you want to do and these in this uh subject group was elite athletes and they're and they're doing a workout that's at zone three intensity so the analog to that would be just below lactate threshold intensity if you're running or we would call it tempo run for a normal athlete you need at least about 35 minutes of work for any one particular workout in order for that workout to make a darn and i don't think it matters if you did four workouts per week or five workouts per week i don't think that you'd get a really big adaptation with with that little let's just say we had an athlete that did 25 minutes of tempo run which would be that's a pretty common workout right three by eight that's not exactly 25 minutes i know but it's close so we'll do three we'll do three by three by eight minutes on four minutes easy that workout is going to be at about that athlete's lactate threshold and for a normal athlete i would say even if they did four or five of those workouts per week which would be hard that would leave the athlete trashed i don't know if i would want to do that i think at the end of the day if you did that for 12 weeks in a row as they did with these uh with these subjects you're highly unlikely to get any sort of meaningful adaptation and so you've done a

shit ton of work with very little if any reward so that that's the piece that's the biggest piece that i take out of this is this minimum time of exposure at a particular intensity in specific to this to this study that zone three tempo run lactate threshold and for any normal athlete it's at least 35 minutes and obviously for these elite athletes it's at least 38 minutes because that's the protocol that they were using i mean it's probably 45 or 50 minutes for these types of elite athletes so if you get that you're on the right track that that's that's the biggest thing is the time of exposure that i that i take away from this because clearly it's a lot of work with no reward so do you want to summarize or add to that essentially like what you know we have three primary types of intervals that someone might be doing vo2 max um tempo and steady state for example like what is the what are the minimum doses for those intensities for people who are going to make up their own intervals and do their own interval math at home yeah 100 so you corinne as you alluded to we use really simple workout vocabulary where we only have like five names for workouts and that's it we don't call things like the betty workout or the suzy workout or the corinne workout or anything like that we kind of we delineate them across intensities and the the primary flavors are from most intense to least intense are running intervals which are in quotes vo2 max intensity i know it's not exactly at vo2 max but it's close to vo2 max intensity tempo run which is close to lactate threshold intensity

and steady state run which is the most ambiguous of all the three and it's really hard i don't even want to describe that in this podcast that's another three hour podcast right there but it's less intense than tempo run let's put it that way right corinne yes okay so to answer your question the minimum amount of time and intensity for each one of those is at the vo2 max which is running intervals it's about 12 minutes maybe if you had a super entry level athlete do 10 minutes they'll probably get some some kind of meaningful bump from it but if you're aiming to improve vo2 max or if you're doing a workout that is close to your vo2 max you need at least 12 minutes of exposure and so the way that that would look would be six by two minutes hard two minutes easier six by two minutes hard one minute easy or or six by three minutes hard three minutes easy for 18 minutes of exposure something like something like that you could you could also contrive the workout to be super short which this research group does a lot where they study like 45 seconds on 15 seconds off and then you accumulate you know 12 or 15 minutes and things like that that's a way that you could design it absolutely can work benefits and drawbacks with that compared to a longer interval there they're absolutely there are absolutely some there but but it can absolutely work but the big thing is the time and intensity of that at that at that high intensity for running intervals what we call it the minimum amount is 12 minutes and

i would say the maximum amount that you could do for a really good athlete it's maybe 26 minutes or 28 minutes for like a really really good athlete and the reason i say it's the max the reason the maximum gets uh or the way that we back into the maximum is that we're looking for an athlete to be able to sustain 90 of their vo2 max during like the second half of the interval they need to eclipse 90 of their vo2 max in order for the for all of the adaptations to kick in and typically when you have a volume that's over that the intensity therefore goes down right because volume and intensity are a teacher daughter so anyway that's what i'd say 12 minutes at the very minimum 25 maybe 28 minutes 28 minutes at the very maximum for an elite athlete then you go to tempo run that's what we were just talking about greater than 35 minutes so you're talking about four by eight you know it's 32 minutes for a normal uh for a normal athlete four by eight eight minutes hard four minutes easy you can reduce the recovery uh interval down to three or two minutes like they did in this particular study and i think it kind of accomplishes the same thing and then we get to the super ambiguous one which is called steady state runs corinne is laughing you guys cannot see that that aren't watching the youtube version of this um and that's because it's not really tied to a physiological phenomenon so running intervals the physiological phenomenon that it's tied to is vo2 max not the same as vo2 max it's tied to it

tempo intervals the physiological phenomenon that it's tied to is lactate threshold it's not the same as lactate threshold it's just tied to it steady state intervals it's really not tied to any physiological phenomenon you might be able to say it's like the onset uh of blood lactate accumulation like right when you get above that first little rise and lactate on a lactate test so right around like two and a half millimoles two millimoles or something like that it might be close to that in some athletes but it's super ambiguous not nearly as clear cut as threshold of vo2 max so the amount of time the minimum amount of time and exposure at that intensity is 45 minutes up up to two you could do two hours of intensity at that there's a really big range and what we found corinne you can opine on this as well what we found is athletes have the hardest time wrapping their head around that particular intensity because it's so close to their normal endurance runs and it's not as hard as a tempo run and so they're kind of in no no person's land from an intensity perspective yeah it's a really kind of odd odd intensity to be at but it's really practical and we use them i would say like skiers would call them natural intervals um which is like you go for a long run and you have natural intervals which means like you're running the uphill as opposed to hiking it for example and that could push you to tempo to like lactate threshold for sure but um it can kind of average out to more of a steady state style um or maybe aerobic threshold i'm not sure if that would

be kind of in that zone um that would be a kind of a good place for that to be so it's an efficiency thing i think more than anything yeah i think aerobic threshold or onset of blood lactate accumulation would be the closest physiological phenomenon to a steady state workout that i could really think of but all those terms are so at that intensity they're all kind of so fuzzy and it's harder to test for so there's a method to our madness is what we're saying there's a reason why my athletes hate me no they don't maybe some of them do i don't know when i prescribe intervals the way i do there's always there's always a method to the madness i'm trying to elicit you're trying to elicit a amount of time at a certain intensity that's tied to vo2 max or lactate threshold or aerobic threshold um but the idea of making them fitter and faster and you know hopefully we get to race again and that becomes performance you know inducing as well enhancing yeah this this concept of minimum time and intensity was really hammered home to me by one of my early mentors who i was who i had on this podcast several weeks ago jt kearney and he came over from the olympic training center with that background similar to with access to similar types of athletes is this research groups are really high caliber athletes and he could also see very acutely in their training if they had enough time and intensity for each particular intensity to elicit an adaptation and every every workout that i would do

or every workout that i would program for an athlete that i had to run by jt that was his first filter are you doing enough time at this intensity to elicit the adaptation and i never got it right the first year and i got it like 50 right the second year and then third year i got it you know like 75 right and then maybe now i get it 90 90 right but it took i mean it just took i guess the the the point of that background story is is that as corinne was alluding to there's a method to our madness that's kind of been uh formed by all of this practice over years with seeing high performance athletes and high performance uh physiologists kind of help help drive what these time times at intensity are yeah and i think some of us are probably sitting here saying oh that's so many intervals um and this is obviously you know we could opine on this for forever but that's part of the reason why like you know some people are going to use a seven-day week some people are going to use a 10-day week that's why a 12-week study might become a 13 or a 14 or a 16-week intervention for individual athletes and their individual needs and on top of that too it seems like a lot of intensity but if we looked at the grand scheme like these athletes routinely put in a thousand hours these skiers particularly cyclists are very similar they're putting in a thousand hours a year potentially i did that for years 750 to a thousand hours it's a lot of training time so even though they're doing this much intensity they're doing a ton of very low very easy intensity in conjunction with this and so

it's kind of interesting when you look at the the how much this feels like a ton of intensity but then when you look at the big picture of how much training they're doing it's actually a very small amount of their like total cumulative hours every year of training yeah the denominator is really big if you put the if you put the time at intensity on the numerator and the total time on the denominator the denominator is really big partly because they're elite athletes and they have a lot of time to train and first cross-country skiers they've they i'm gonna make a statement probably regret it but they very rarely get overuse injuries like musculoskeletal types of overuse injuries compared to runners there i saved that statement at the very end at least compared to runners they've so they can do these super high volumes and there's not as big of a consequence yeah and part of that too like and i think you know cycling is a little different in this sense that cyclists primarily ride bikes right there they don't do a ton of cross-training skiing cyclists only ride bikes like skiers are and this is like from coming from a ski background from you know being part of that world skiers are like the world's best cross trainers obviously they do a ton of roller skiing and i'm so glad i never have to roller ski ever again and they do obviously a ton of time on snow skiing as well but they also ride they also bike they also run and hike um they're obviously most efficient for the most part on their skis but because of that too

i think that that allows them to spread the volume out over so many modalities successfully that that's going to cut down on overuse injuries versus a runner who's got high load on their body plus they're primarily running and cyclists who have no load on their body but because they move in one plane so much like they potentially are at more risk maybe for some overused stuff than than skiers are skiers are just a weird fun breed of humans fun breed of humans i love it that i mean the what you're alluding to the musculoskeletal risk for runners that honestly is the biggest piece of valid pushback whenever i present these training concepts of uh concentrate your training or do block style training or kind of whatever that's the biggest piece of valid pushback is that cross-country skiing and cycling which these uh studies are typically done on is not running and there's a musculoskeletal or an orthopedic consideration for running i get it i told and that and that's why i say i would not do the exact same intervention but there's a way that you can do it and mitigate that orthopedic risk you can do the intervals uphill you can give it a little bit more spacing the themes reign true because it's a it's an endurance sport it's an aerobic sport and the adaptation is going to be very similar the themes reign true but this specific way that you apply them would be a little bit different and so let's just take this for an example right the one of the key workouts that we are focusing on is six by 12 with three minutes recovery and i mentioned that i would i would not prescribe i probably wouldn't i don't think i've ever prescribed that for any even an elite trail uh mountain ultra runner that much time

and intensity so automatically off the bat i'm skimming some of that time and time of intensity maybe it's like 65 minutes or 70 minutes and maybe there's a you'd prescribe six by 10 minutes similar but different but i'd also give them a little bit of recovery yeah like like 50 recovery versus 20 to 30 recovery yeah and once again that might be skinning the cat to you know or slicing the hair too fine what analogy did i want to use of uh that that might be like too small of like a like a difference to really you know to really to really make any sort of meaningful impact but my point is is the themes from other sports from other endurance sports that we see in the research can absolutely reign true and ring true in running but you do need to consider whatever the sports specific mode whatever nuances there are in the sports specific modality and i think when we're applying non-weight bearing sports or not as weight bearing sports to running the thing is is spacing the workouts out maybe a little bit more or and maybe taking a little bit of vol of overall volume time time and intensity overall volume off of the table because of the risk of musculoskeletal injury which makes sense just because the overall training volume on a yearly basis for a cyclist or a skier is going to be significantly higher than that ever runner just from an hour's standpoint by a lot by a lot because they'll just get hurt the runner will just get hurt

yeah all right we kicked this around enough corinne that was really fun so nobody out there don't go do six by 12 go to five by 12 or five by 10 that's a reasonable workout that's a reasonable workout i prescribed a lot a lot of my athletes but if you're choosing to do four workouts a week versus two workouts a week with the same amount of total time of intensity pick two it's probably going to do you a little bit better and i would say that there's it's highly unlikely that your risk is increased all that much i'm nodding but yes i i agree sorry i keep forgetting it's a podcast yes i would agree with that that's gonna be the best bang for your buck and it's gonna be um what likely is gonna give you the biggest improvement yep all right there we go perfect thanks corinne and there you have it there you go much thanks to corinne for coming on the podcast today and nerding out with me on this particular paper what did you guys think about the format it was a new one uh i liked it a lot i thought there's a lot of actionable information that any of the listeners out there can really apply to their training tomorrow or even later in the week but you guys let me know what you think about it you can hit me up on social media i always appreciate all of that feedback and if a coach like corinne or any one of our cts coaches is a good match for you and you think that can help you with your performance maybe you've got a really cool

event lined up next year that you're really psyched about if you think that one of our coaches could help you get closer to your goals we would love to have you on board as a cts athlete as we went over during the podcast we coach a number of different athletes from some of the best in the world to everyday athletes that are just trying to do their best at whatever ultra marathon they're getting prepared for and we love every last single minute of coaching if you think that one of our coaches is the right coach for you go ahead you can hit me up on social media i'll find what that right match is if you want any information about any of our coaching packages you can head on over to trainright.com all the information across all of our coaching packages is on that website the link to the website will also be in the show notes i appreciate the heck out of each and every one of you listening today and as always we will see you out on the trails