Alena is a PhD in Integrative physiology at the University of Colorado, Boulder. She specializes in biomechanics and specifically prosthetics and other mechanical assistive devices.
You can see Alena’s TedTalk ‘Put Yourself in Someone Else's Legs’ here.
Information on CTS coaching packages: https://www.trainright.com
trail and ultra runners what is going on what's happening welcome to another episode of the KoopCast as always i'm your host coach Jason Koop and on this episode of the podcast we have alina grabowski who's a PhD in integrative physiology at the university of colorado boulder alina specializes in prosthetics and performance implications for amputee athletes she was involved in the famous oscar pastorius case as well as provided expert witness testimony in the more recent case with blake leaper who's another paralympic athlete in the sprint events if you've not heard of blake's story stay tuned because we go over it all during the course of this conversation this area of performance is fascinating to me and i wanted to bring on alina to geek out a little bit on how prosthetics work and if they provide an advantage or not alina has this keen way of making this complicated area relatable as well as understandable and has this ability to humanize paralympic athletes far beyond their hardware in what the human eye can see and i have to say it was a joy to speak to her in these areas as an aside to this podcast i encourage all of you to check out alina's ted talk on this subject which i will link in the show notes so all right i can get out of the way let's get right into it here's my conversation with alina grabowski
i've had a lot of like internal and innate curiosity in this area because we actually work with a lot of the paralympic cyclists and we've had our coaches work with them for for for years um across a lot of different disciplines on the road and on the track and a lot of those different a lot of different categories and so we've always tried to keep up with research in in in the in the kind of prosthetic area because their technology is changing all the time as well totally and we actually have a new study on paralympic cycling that's coming up now too oh cool you want to give a quick overview of that before we jump into some running stuff sure sure um we are interested in how the setup of a paralympic cyclist should be optimized and so we're studying a group of people that have a below the knee amputation on one side and we're trying to figure out if there's an optimal setup in their bike fit such that will change the crank arm length the pylon length and the pedal attachment position whether it's beneath the forefoot of a shoe with a prosthesis or whether it's just beneath the pylon that pipe that goes up to their residual limb and socket and so we're trying to figure out what's best for that side for the affected side and so we're measuring things like power output metabolic power mechanical power and that sort of thing to try to optimize their setup oh after this i'm going to put you in touch
uh with uh jim lehman who is the uh head coach over there he lives like two blocks away from me and he and i have known each other for years oh that sounds fantastic yeah he'll he'll be super interested in that research i mean our you know my uh my experience my very very limited experience with that is when we would get these athletes in and we've been doing this since kind of the mid-2000s it was it was always this combination of trying to use best practices and making stuff up at the same time because we bring them in and we do bike fits on them and we didn't know whether we needed to put them in the normative ranges for ankle flexion and knee flexion and hip flexion and things like that for their affected or unaffected side and it was always this it was always this really interesting thing amongst our coaches because we were all doing it for the first time or second time or third time like very small numbers whether it's a bike fit or training protocol or whatever and it took a lot of us to just barely make heads nor tails out of a lot of those situations those of you who aren't watching the youtube vision of this alina is like laughing her head off because she certainly empathizes with that totally totally so try to put a little science into it and uh see where we can get but you're right there's a lot of subjectivity that comes into trying to figure out paralympic athletes there's not a lot of studies on them and each person's got a unique setup uh sometimes on purpose
right maybe they have a unique injury in addition to having an amputation so all those things play a part and that's why it takes so long so many brains to you know put everything together and try to make the best thing happen how did you initially get involved in it because this is a niche of a niche of a niche of a niche right i mean not only is it olympic sport olympic sport is a is a small enough niche uh as it is and then once you get into paralympic sport not to demean or degrade those athletes they're actually fantastic athletes in their own rights i've seen a lot of them firsthand and it just blows my mind uh how good they are but how did you initially get involved in it yeah i was a postdoc uh at mit so that's like a research position that you take on after a PhD and doing some work with a guy named hugh her and he's an interesting person all by himself i'll just say that he's he's a a former well not a former climber he's still a rock climber and he has two amputations below the knee on both sides and in fact had his amputations because of a climbing accident a long time ago and uh i chose him as a mentor for my postdoc and we were working on a few different projects we were working on powered prostheses we were working on exoskeletons and then along came this guy named oscar pastoreus um he's a sprinter from south africa who was exceptional he has bilateral below the knee
amputations and is competitive in the 400 meter sprint to the extent that he could compete in the olympics if he was allowed and so we did research on oscar to try to understand his use of prostheses and whether he should be allowed to compete in the olympics and um through that we got involved with the court of arbitration in sport and all these different you know international organizations that regulate if athletes should be allowed to compete or not and we used our research to basically um appeal the iaaf's decision that had banned oscar from competing and then that appeal through the court of arbitration in sport allowed oscar to compete in the olympics which he did in london in 2012 and to make a long story short that piqued my interest so much in like how does a prosthesis work you know and is it different than a biological limb and how is it different and then can it provide any advantage or disadvantage and so i really got interested in that niche and then just kept going with it and in fact it's a large portion of my research right now in looking at how running prostheses affect performance in athletes with amputations i want to talk about that a little bit because i think how i think that last piece that you mentioned how running prostheses affect athletes is really underappreciated by the general public because most most
people who follow running or they follow track and field they're aware of the oscar pastoria but their level the level of detail of which how they how they know how those things work is watching him on the track and their viewpoint with that is they can say okay he's behind here he's ahead here he's behind there and here's the and here's the finish of the race but they don't appreciate the nuance of a this whole this whole arc of a team of scientists looking and saying his legs provide him an advantage and then another team of researchers and scientists saying the exact opposite to get him to the point of actually being able to compete in the olympics and we're not going to touch everything that has happened since the olympics because that i know that's not your world and it's a very tragic ending to to uh to to the story but i do think that that my point with that is is the how people view this is is greatly underappreciated so can you kind of take us through what the original german research team was saying about how he was able to gain an advantage and then how you looked at the problem in this completely different manner sure sure yeah so um it's it's a layered case i guess so let me see if i can start in a place that makes sense so um oscar was extremely competitive and was posting really fast times in the 400 meter and so the iaaf at the time had a rule where they had the burden of proof
to show that prosthesis provide an advantage or disadvantage to an athlete so they hired a team from germany who did a study on oscar and through that study they did a number of measurements the one that they pushed forward was that prosthesis allowed oscar to have a energetic an energetic advantage in the 400 meter sprint um and it was like 25 or something like that so it was a large supposedly a large advantage and we dug deeper into that and looked at what they measured to try to get to that result and they they had a fundamental flaw in their measurement they um had oscar run a 400 meter sprint along with i think three or four other non-amputee athletes who were recreational athletes and they measured oxygen consumption and they used that to say that oscar had an advantage in the last hundred um if you have taken sort of class in exercise physiology or have any indication about you know what oxygen consumption means it's it's aerobic metabolism it's a submaximal measurement and we take in the lab we need about five minutes to get to a steady state so that we can have a gold standard measurement of how much effort someone puts forth now oscar competes in the 400 meter sprint in
less than a minute and it's definitely not and he uses a combination of aerobic and anaerobic energy and anaerobic energy can't be quantified accurately in performance um it's a really tricky measurement and aerobic metabolism needs to have a set measurement protocol so that we can actually use that measurement and have that gold standard and so we did that with oscar and found that there was no difference in his aerobic metabolism and so that was part of the basis for why the study done by the german team was flawed we also did a bunch of other measurements with oscar to try to compare his biomechanics to non-amputees and that's probably just more interesting from a science perspective um but from a performance perspective by all accounts he was either um equivalent like in his sprint endurance which is a measurement that we do in the lab um or he had a what i would consider a big disadvantage in his biomechanics in his um ability to get out of the starting blocks which we didn't measure in that study but i wish we would have um so anyways we used all that data and gold standard protocols to show that that german study was flawed and that there was no advantage due to the use of prostheses and one of the things that that your group particularly focused on in that
case was the amount of force production that oscar that asked that the amount of force that oscar could produce and then the rate of that force production which is critical in any sprint event including the the 400 meters and to kind of speak to the disadvantage that you're alluding to one of the primary pieces of that disadvantage is that he was not only not only could not produce as much force but significantly less force than his counterparts correct yeah so his biomechanics to achieve a given speed were really different and to run faster you need to be able to put more force on the ground and the prostheses that he's using are basically simple springs so they can store and return energy but they can't generate energy on them on their own and we've got muscles in our calves and this nice long achilles tendon and muscles in our feet and all these different biological tissues that allow us to generate force and change the amount of force that we generate on the ground and prostheses are not like that they're just a spring and they're made of carbon fiber which makes them look unique so people see them they think oh it's different it must be better right but it's not especially for sprinting it's not better it's um it's not able to generate the power that you need to go fast i remember looking i remember observing what was going on from the outside looking in and this was
right around the time i mean it's a little bit after some of my undergraduate studies but i had the same interpretation right out of the gate with the german study is what you guys noticed i'm like you guys are defining the wrong performance determinants like that is not what limits performance in the 400 in the 400 meter dash like any rational coach could look at that and go that doesn't make that doesn't make any sense that's like saying a high jumper's performance is limited by their vo2 max or something like that like that's that's the kind of thing that they're that they're looking at so i was really appreciative when you and your group kind of went back and said no no no no this is what sprint performance this is what determines sprint performance and this is how this athlete is affected via this w double amputation along those parameters totally totally and it does there is a contribution but you need to be able to measure it correctly first so but you're right there are there's specific things that influence performance and then there's really random things that don't so you really have to think about that when you're trying to compare athletes with and without amputations either using prostheses or using biological legs and it's a tricky comparison um we we kind of got into that with uh blake leeper who i think we'll maybe talk about in a little bit um but it's really difficult to make that comparison and that's really what's driving my whole research program is to try to think about how can we experimentally
scientifically look at someone with an amputation using a prosthesis and compare it to them if they had biological limbs can't make that comparison directly um but you can try to use different athlete cohorts to try to make those comparisons and go from there yeah it's it's fundamentally an apples and oranges comparison you just try to get it like as close as you can um we can bring up the blake leeper case i'm really glad that i caught you now and not two weeks ago when you couldn't talk about this because this is another fascinating case that i i can guarantee you three or five percent of the listeners if that have heard of this so i'll kind of set the table and then you can you can come in and fill in the gaps since you were way more intimately involved in this uh than i even realized um so blake leeper is a 400 meter runner double amp double below the the knee amputee runner in the united states that was in a similar position to oscar where his performances were kind of putting him right on the cusp of him making the u.s team which is a really big deal because the u.s historically has had fantastic world-class 400 meter runners in fact if we put our 10 best 400 meters runners up in the olympics they would get the top 15 spots or something like that i mean they're very very very good so it's a it's it's a big deal not to diminish oscar's accomplishments but this is this would be a very big deal so he was right on the cusp of the olympics and in fact
in the world championship trials i believe he was fifth which would have put him in the relay pool is that right okay so he was fifth and he was going through the same process through the court of arbitration for sport where they're trying to determine do his legs provide him an unfair advantage and the one of the critical differences in his case is that the the the opponents i guess if i can characterize them correctly saying that he had an unfair advantage we're trying to position the height of his legs as the center point of this unfair advantage meaning he had longer legs to utilize throughout the course throughout the course of this race just what was it alina two weeks ago before we started speaking like two weeks ago this course was finally settled not in his favor the the court of arbitration for sport ruled that um uh that his legs did provide him an unfair advantage compared to his able-bodied counterparts and you were part of that so why don't you give us any sort of detail or nuance that you learned from that whole process sure sure so um so blake leeper is faster than master pistorius and so that's uh a really interesting and kind of compelling thing all by itself um i worked with blake probably about two years ago so to set the stage a little bit when um when oscar was about to compete in london in 2012 the iaf changed the rule about prostheses and they put the burden of
proof on the athlete instead of on themselves um they did it quietly no one really knew about it and then we started digging in a little bit more into that rule and we're like huh that's interesting now there's a another additional burden on the athlete so which is weird by the way let me just throw in my professional coach commentary that's a weird rule to have and not one that i'm generally in favor of where you where the athlete has to say okay i'm good i'm clear like i have to come up with all the proof myself i fundamentally that's a tough policy for me to get on board with there's my commentary for that you can continue yeah and you have to you have to prove that you're not guilty so that the rule is that the athlete has to show that his prostheses do not provide him with an advantage okay so that's the change in the rule and then as blake became faster and faster in 400 and trained harder and harder by the way yeah he and i were in touch and i said okay the rule has changed do you want to do a study and see where we stand because he had been talking a lot about wanting to compete in the olympics i mean i would do if i were caliber that's amazing and so he and i got together and i assembled a couple other scientists um owen beck and paulo toboga who are fantastic we came together in boulder and did a bunch of tests with blake to try to address that
exact rule do prostheses provide an advantage compared to biological limbs we did a series of tests with blake we had five performance metrics that we believe and i think everyone believes really strongly influence 400 meter sprint performance one is the starts so how fast can you accelerate out of the starting blocks the next is the curve how fast can you run on a curve your maximum speed on a straightaway has an influence on 400 meter performance your aerobic metabolism does have an influence on your 400 meter performance so we did measure that using a gold standard measurement and then finally we measured his sprint endurance and so i can kind of break those things down a bit and go through each of those performance metrics but basically the first is the acceleration out of the starting blocks and um you can even visually see in a race that athletes with amputations struggle getting out of the starting blocks it makes sense again they're running on spring so they're not able to really push hard on the blocks and so blake was um about 25 slower than non-amputees roughly um that put him at a about a second disadvantage in the first hundred of a 400 meter sprint around the curves we had him do a series of curves sprinting so we had him run at maximum speed around the curve
on a typical regulation 200 meter track curve 400 meter track curve and then we compared that to his straightaway and that's been done in the past in other studies where they've compared non-amputees on a straightaway and on a couple curves with different radius and basically blake slows about three percent more than non-amputees so that's a smaller disadvantage but still not as good as non-amputees so he's a little slower much slower in the start a little slower on the curve his aerobic metabolism was about the same his maximum speed and biomechanics actually were interestingly about the same which was really cool to see so he's able to somehow across a range of speeds up to his maximum speed elicit nearly the same biomechanics as non-amputees which is different from oscar yeah and so why is that different like and you might need to get in the weeds a little bit with how his legs are designed versus oscar's and to be honest we don't totally know the answer to that question we can just speculate that it could be because his prostheses are a little taller than oscar's were it could be because his prostheses were less stiff meaning that they can move a little bit more with a given amount of force than oscar's oscar's and that's about as far as we can get as far as what might be different
i'm i'm thinking that his technique from a coaching perspective his technique is also very different compared to what oscar's was um but it's so compelling that he's able to get to the same fast maximum speeds as non-amputees and then use nearly the same biomechanics so you guys presented this case and you're basically taking this performance humpty dumpty and breaking it apart right to these to these four components two of which you say are par and then the other two have disadvantages associated with them yes the court of arbitration for sport came out and i'm i'm i'm i'm taking like the dumb lay person's um uh synopsis of their of their version and they said well his legs are just too tall yeah so to fill the gap in just a little bit we gave that all of that information we also measured sprint endurance okay or um how long you can sustain a given maximum speed on a treadmill and blake's values were right along the same as non-amputees so he was never better than non-amputees always a little bit worse or substantially different in the starts and turns we gave all that information to the iaaf um and then they took a fair amount of time to make the decision that they were not going to allow him to compete and then we appealed that decision and took it to the court of arbitration and support now that was about a two-year process that i just described
um and then the court of arbitration and sport we we had to delay it a bit because the olympics got postponed uh covid has been a challenge and so we actually weren't allowed to do that in person we we had it online the court of arbitration and sport hearing um but yeah they made a decision they made two decisions for cast the first was that they changed the burden of proof to be back on the iaaf because they ruled that it was an undue burden on an athlete with a disability to try to show that prostheses provide an advantage or disadvantage so it's the rule changed that's good it's back on the iaaf that's good for the future but then in the second part of their decision they decided that he was that blake was too tall and so he shouldn't be allowed to compete and they um cited the international paralympic committee rule which is also a bit controversial that i've been a little bit of a part of in trying to understand where that rule is coming from and what they're basing it on but the international paralympic committee rule has a maximum allowable standing height for athletes with bilateral amputations i did not know that for all sports every athlete with bilateral amputations that's competing in paralympic track and field
oh track and field okay needs to be classified and they need to make sure they're within a maximum allowable standing height and this is also controversial because that rule by ipc has changed probably about five times in the last 10 years and they are making this height and they're setting it based on barefoot standing height of caucasian and asian people yeah yeah not a good not the most comprehensive cohort no and so it's the studies that were done to try to establish what height should be are good they're using anthropometrics meaning that they're measuring things like your wingspan your seated height your ulna length your femur length and they're taking it into a formula and they're trying to predict how tall you'd be but they're just using a subpopulation and that doesn't really reflect the diversity that we have especially on the u.s track oh gosh and it's it's been shown by other studies in the literature that there are differences in leg length relative to say torso height of african americans versus caucasian americans it's um so it's a challenge and it's um i i'm disappointed in the second rule
sure i can certainly see that and i didn't know that level of nuance i really appreciate this this is a it's an it's an incredibly nuanced and fascinating area and it's hard to come up with good solutions because everybody wants to be on a level playing field um in the paralympic games and you have this inherent non-level condition where you have athletes that have all different types of uh prosthesis that they that they have that they're available to they have all different types of injury conditions kind of going into it they're competing across all different types of events and sports and sometimes sometimes those artificial limbs like do different things depending upon the sport whether it's a jumping sport or running sport or sprinting sport or endurance sport and things like that and it's there's only so much time in the day to figure it all out yeah i i can say with certainty i'm glad i'm not a classifier or someone that needs to make the rules that's really hard but if you're going to make a rule base it on science base it on things that make sense towards running and standing height doesn't really translate well that's number one i think you should use something that's more relevant for running like how tall are you when you run and how much does the foot plantar flex and move you know push down on the ground so you can artificially change your biological leg length just by rotating your ankle up and down
yeah and the standing height is just that one angle it's not really how you sprint so it's it's challenging um it's uh i just i guess i wish they would have um looked at the evidence that we presented and used that since that was what the rule is all about uh instead of putting a different rule within the context of this case which is based on the international paralytic committee which is a whole nother organization so um you know athletes with bilateral amputations aren't regulated as to how tall they are yeah we say oh you same bullet you're too tall sorry you can't compete you gotta go we gotta cut that down a little bit um that that seems kind of silly so yeah um i'm not sure where it's gonna end up i know that um blake's legal team right now is appealing the decision the second decision made by cast and we'll see where it ends up so i'm gonna put you on the spot here a little bit i didn't put this in my outline so feel free to deflect this question as much as you want to um you've seen the evolution of this you know throughout olympic sport and as i mentioned earlier there are no good answers but are we getting to a point where some of some of these prosthesis can actually be better than natural legs is that the politically correct word please correct me if i'm not using
so if i'm using something that is gonna offend massive quantities of people here no i think you're good okay are we there yet no we're we're pretty far from it i would say really you'd say it's pretty far from it running prostheses haven't changed in the last 20-ish years really i mean there's some new developments within running prostheses that we're starting to look at which is cool but there's nothing that's like dramatically different that would allow an athlete with amputations to have an advantage that's amazing all the technology that we have and you you have a big enough pool now of athletes it's not huge but there's a lot of there are a lot of paralympic athletes out there um with all the technology and all the focus on it still we can't build things that are better than the human body right and that's true for everything um we're trying i mean there's there are engineers that are fantastic and so creative and trying to make these cool devices that allow us to be able to be better um but there's nothing that works right now especially for sprinting why do you think that we've seen both of these cases at the 400 meters that's a really good question also and it's something that we're very interested in because you don't see it in the 100 or 200 right and it's likely due to the big disadvantage during the start um it seems like 400 meters are it's sort of the sweet spot where athletes
can be competitive they're not able to outperform non-amputees but athletes with amputations can be competitive um there are longer race distances that haven't really been explored yet because paralympics is limited in the number of events that they can have and so um it depends on the year most years they'll have 100 200 and 400 and that's it it doesn't go any longer than that for paralympics um so it's it's sort of a question as to whether the 800 meter sprint might be another place where athletes with amputations could be competitive yeah and i think that seeing seeing these types of things at the 400 eventually the athletes are going to push for that that's my guess right from an observer's point of view kind of like looking in is the paralympic athletes that want to compete in the olympics they can look at a range of distances and the more options that they have that they can be competitive at they're eventually going to kind of command that they're brought into the paralympic games and they can actually compete in the able body olympics as well right right yeah it'll be interesting to see how things progress in that area there are few athletes with bilateral amputations especially those that can compete at the highest level like that so it is
remarkable when you can see someone work so hard and get there get up to that level and hopefully we'll see some of those athletes athletes continue to improve in their performances there's a couple NCAA level athletes that are performing in different events different distances so it'll be fun to see what happens there as well but still there are a lot of misconceptions and I think there are more misconceptions at the collegiate level and then even sometimes at the high school level where once again people like look they just they observe they look and they come up with some rational some kind of like rational excuse in their mind that a person without lower limbs is somehow going to be better than a person with lower limbs and the excuse I've kind of heard it a few different ways oh they're lighter they're quote unquote really good springs you know they're able to provide more traction like they're engineered they look fancy it's a carbon fiber blade you know for heaven's sake like you've probably heard all of those what is your when you're talking to somebody who's like just less informed and observes that how do you go about just educating them on the subject and like kind of bring them back to reality of what the situation actually is yeah I think there's a couple of different approaches but one if it looks different it doesn't mean that it's better so it's hard to
get away from that because it does look fancy it's carbon fiber is it lightweight yeah it is lighter but is it better functionally absolutely not it's a spring we have a great spring in our legs too it's the Achilles tendon right and then we've got all these different tendons and ligaments in the foot and we're able to regulate how those things work and interact together we're able to sense the ground you can't sense the ground with a piece of carbon fiber right the only sensation that person's going to get is through the residual limb which is in a rigid socket so imagine running with a ski boot on that's a rigid socket basically that's around your foot and you can't really feel the ground through that so there's lots of challenges I think and if you really think about the function of that prosthesis it's just not the same at all there's no control the person can't go okay flex the foot and it happens it doesn't it it's sort of a dumb spring in a lot of ways I love that a dumb spring so a lot of ultra runners will be familiar with Dave Mackey's case who I know is right near there near you in Boulder Colorado and there's also been a number of other amputee ultra marathon athletes including Amy Palmero Winters who's done a number of races including the kind of the bad water 135 and I
always feel that I can like somewhat appreciate what they're going through having some experience working with Paralympic athletes albeit in a different sport but to to speak to how much more difficult in a trail and ultra running situation that is I have never been able to to accurately or cohesively explain it to somebody can you take a shot at that in terms of how you mentioned something you mentioned some things about the proprioception that's hugely important in trail running but what are the other things that make those types of accomplishments so remarkable when we see either double or single leg amputee compete in a trail ultra marathon event yeah it's hard to know where to start my mind just went in five different places but it's so prostheses are designed to go forward really well they're not really well designed to go side to side or or do they have any ability to negotiate if you hit a rock or something like that and it wants to throw you to your right or to your left a prosthesis isn't designed to do that it's just designed to go forward well and on flat ground well so we don't really know yet how a prosthesis behaves on a slope but when you're running uphill let's say you really rely heavily on your ankle and your calf muscles to be able to drive you up the hill and if you don't have that it's
really difficult to even start to explain how that must feel or work same thing with going downhill you can't extend your foot out to reach for the ground or you can't really control if you step just a little bit wrong that spring's going to want to drive you in the opposite direction so there's a lot of challenges that are nuanced and hard to explain I think to someone that hasn't had that experience but yet I mean Dave and Amy are fantastic athletes they're amazing and they've told me a few things about you know running especially those ultra long distances that we probably don't need to account for if we have biological limbs things like sweat right in the socket and I remember Amy specifically telling me about how she would stop and basically dump out the sweat from her socket because it just kept building up and then she had the complication I think in Badwater where she from her injury she had a motorcycle accident I believe she lost a lot of neural sensing especially in her residual limb and she got to a point in Badwater where she was actually burning her residual limb without her knowing of it and had 30 degree burns or something along those lines on her skin which kind of speaks to this idea like the sensing and the control are completely different
when you have a prosthesis versus a biological limb. Well one of the things that we've worked with with our Paralympic athletes is just realizing that they can't cool as well because they're missing some of the surface area in order to dissipate heat which that is lost on most people they're like well like what does that make a difference right that muscle's not generating heat so therefore it doesn't need anything to dissipate from but just the fact that there's not the surface area there that once was there we see and I actually don't know you would know better than I do I don't know if there's a lot of research actually in this area but we just see those athletes don't tolerate the heat nor do they tolerate heat acclimation protocols quite as well yeah and that makes sense from a circulation point of view too I think that's what you're relating to but yeah I don't know much research in that area I know there are some folks that are working on socket cooling technology so trying to come up with different liners or different materials for the socket that goes around the limb to try to regulate the heat that's experienced in that residual limb but on a whole on a whole body level you're still gonna have some challenges with heat yeah so suffice to say if you ever see Dave or Amy or anybody else out there on the trails training doing a race give them way more props than you think they need because what they are doing is
so much more enormously difficult than what you are doing at the same place in the same time totally fair statement and Dave's a really humble guy and he would not say that but I can I can say I can say it for him since he's such a nice guy I appreciate you like coming in with your expertise and as I mentioned before the podcast a lot of this is just me kind of geeking out and satiating my own personal curiosity I think the listeners will find that fascinating as well but I'd be remiss if I didn't do a little bit of a hard pivot towards some more kind of ultra ultra running stuff and one of the fascinating pieces that we have within that sport is that is it really combines different modes of transportation it combines walking and flat level running uphill running and downhill running and I've always viewed coaching ultra marathon athletes through the lens of training them for these four different sports because they are slightly different it's not like you know high jumping and and uh and distance running it's not that different they're all connected by the aerobic system but they're different enough that you need to take them kind of under consideration and I know a lot of your research in in your area has to do with quantifying walking from a biomechanical standpoint and running from a biomechanical standpoint across all of these different kind of modes uphill downhill flat different speeds and things like that this is going to be a really hard question for you to
answer in a short amount of time so it's so forgive me for it forgive forgive me for asking it for the onset but if you from your biomechanics lens could describe how different biomechanically all four of those different things are just from a joint mechanic standpoint or force you know standpoint however you want to pick it how would you describe that to somebody that is just trying to like learn about the sport learn about how to get better at it yeah that's a big question to answer quickly so we have done a lot of research looking at walking and running on different slopes and at different speeds to try to use that information to think about assistive device designs like prostheses and so it is really important in that regard it's also important in understanding ultra marathons which I love as well and have luckily had the chance to do a few in my past but yeah there's I mean there's different coordination patterns and different forces that you're exerting on the ground you're changing the muscles that are active and you can probably figure that out after you've been running uphill for a significant amount of time that your calves start fatiguing and you may want to you know you have to sometimes shift a little bit to make sure that you don't completely wear those
out so I guess to put it succinctly to go faster on level ground and on different slopes you're going to elicit the calves more and they're going to be pushing harder on the ground at the ankle to go uphill that's similar to but you're also eliciting the hips and muscles around the hip and going downhill is really that eccentric contraction the quads and sort of using the knee to absorb energy and so you'll find that and you'll feel that in those muscles surrounding each of those joints of course as you're going a longer distance and definitely for a sustained pitch can you put can you somewhat synopsize how different those that how how differently we use those muscles either in terms of force or the joint torque as we go from running on flat level ground to just a normal grade 10% grade or something like that like how different how different is it from a biomechanical standpoint when we change running across those different conditions yeah it's a good question and we're right on the cusp of trying to get those percentages more precisely but I would say that the the torque at the ankle and
the hip are going to increase to go uphill and and the torque at the knee is going to increase in magnitude in the negative direction to go downhill where the knee and hip are going to stay about the same compared to level ground so all the joints are active in in in going uphill but the the percentage I guess or the importance of the ankle and hip are are increased for uphill and the knees increased in magnitude for downhill yeah and we see this with athletes where some of them are really good in one of those modes they're really good on flat level terrain they're really good in the uphill they're really good on the downhill but they might be worse across some like something else and I've never I mean as my coach bias talks it up to just training right they train more on the uphill they train more on the downhill or things like that is it as simple as that or are there some like natural like bound like just inherent biomechanical properties or physiological properties that they have that would allow them to excel uphill downhill or level and I mean you could even take it as soon as simple as hey listen their you know power to weight ratio is different so that's what's enabling them to go uphill it's it's a great question that I don't have a good answer for I'm afraid is is trying to tease that out and whether there's like a
physiological or biomechanical benefit for certain athletes on the uphill versus downhill let's say I don't know if there is something like that I can imagine that there could be and maybe that relies on sort of a force effectiveness or how you're exerting force on the ground how your legs are lined up and how the ankle knee and hip are aligned with that that force that you're exerting on the ground to me that seems like it would be something that you could work on and train for and think about because that would then potentially if you can align that better you might be able to reduce your metabolic cost which would then benefit you in the long run so um that's my yeah I it's a tricky question to answer so I'm not sure that I have that specific answer but that's my hunch yeah I mean what from a coaching standpoint that's been my hunch as well and there's there you mentioned there's not a lot of research on it and whenever there isn't I always just take the I take the the very blunt and kind of gross okay we just need to train for the demands of the event and if the event has a lot of climbing and descending we're going to do a lot of climbing and descending if it doesn't have a lot of climbing and descending we're not going to do a lot of climbing and descending that's just kind of like the stupid default to go to but I mean it seems to work to a lot of extents you know yeah for sure so
whenever you I mean you mentioned you're an ultra marathon runner and I'll I'll have given you the intro to this podcast on some of your ultra marathon accomplishments do you look at that through your biomechanics lens every once in a while like when you're out on the trail and you're like oh my gosh I'm gonna I'm gonna have a whole lot of you know negative joint forces when I'm running down this hill and things like that like what are the things that come to your mind when you're out there on the trails yeah you know it's it's interesting I I do sometimes think of that and I think of it more from a effort standpoint than I do from an injury standpoint and maybe that's just because I haven't really sustained knock on wood I haven't really sustained any injuries in my running career which has been great but yeah I mean I do think about stuff like that I think about it I guess now I really think about how would this terrain feel if I had a prosthesis or you know what device could change the way I'm running how does footwear have an impact so there's so many different things that we're lucky enough to be able to change and think about so those things definitely go through my head when I'm on long runs and you bring those into the lab or into the students that you teach as well definitely definitely yeah in fact um a fun story I think is uh I have gone on runs a lot with my colleague Roger Crone and I'm not sure if you've interviewed him or not but he's uh he's also really intrigued
by the biomechanics metabolic cost of running and we would go up to James Peek and do a trail run and so he would start um speed walking and I'd be jogging and and we would look at each other and be like uh you know which one's better should we be walking or should we be running it's the same slope and he's also you know hand taller than me for sure but um that led to a study that he did in his lab where he looked at extreme slopes and he looked at the different metabolic costs and biomechanics of running or walking at a given steep slope and tried to figure out where the best transition would be and if there is one and so I think there's still a lot to learn in that especially when I think about our height difference and how that might have an influence um but it seemed like right around 30 degrees was sort of that switch point where it might be better to walk than to run but I don't know I still enjoy running and the feeling of that in my body so um it's hard for me to walk when I'm going to those deep steps oh that's so hilarious so I don't think you knew this I actually took an undergraduate biomechanics class from Roger way way long ago um and I can always remember him coming into the classroom with those personal experiences sometimes from the weekend before and he would completely change his lecture about what he had just experienced I do have him on the
docket to get on the podcast we are going to specifically talk about that but the listeners will remember maybe five months ago I had one of our mutual friends on the podcast Jackson Brill who is obsessed about the walk to run back to a walk transition point and how grade and speed affects that and we will probably have him or you or maybe all three of us back on the podcast to talk about that as this starts to get teased out more and more because in an ultra running from an ultra running perspective I actually think and I've I've seen this up front I think that that's a big performance determinant like having the athletes have the ability to say I'm going to run here and walk here and run here and run this little part and figure out that piece of the puzzle that comprises how they're ultimately going to finish the race and we do not have good answers to that we don't have good answers to that at all I think right now right and I think it it plays into fatigue a bit too yeah so and how to maybe mitigate that by changing from walking to running or vice versa and that's from personal experience not from the lab um how to tease that out and then figure out how how it looks throughout the course of a race and right if you know if an athlete has an inclinometer and goes oh it's you know a little more than three degrees I'm gonna walk here or how do you do that I mean how do you organize that I think it's it's really interesting to think about yeah maybe we look to our best runners and and see what they're doing to get a start and
then do something fun in the lab yeah well as always when I have one podcast with somebody who's really smart I come out with four more podcasts so thank you for continuing that tradition Alina I really appreciate it listeners can look forward to that again and again and again we'll bring Jackson back back on the show he's a delightful uh young athlete and young student as well yes totally all right we're gonna leave it there I I can't tell you how much I appreciate your time and expertise and indulging me in satiating all these curiosities I've had with these elite amputee athletes I just think it's a really fascinating area and I have I really appreciate professionals like you that can bring this to the public and also educate us including myself on what's going on with these athletes in an effort to just create a fair equal level playing field that is also fair for each individual out there that's trying to accomplish something uh some of their dreams where can people find any of your work and uh anything kind of like related to your lab if they are curious that I'll put in the show notes yeah um I would say probably my website uh within the department of integrative physiology at CU Boulder I can give you a website link if that's easier perfect we will do that we'll put that link to in the show notes I will also shamelessly put your TED talk that you did at TEDx Boulder in the show notes I encourage people to go check that out it was really fascinating and once again Alina we really appreciate your time yeah thanks so much it's been a
pleasure all right and there you have it super fun podcast really really good time talking to Alina today I just can't tell you I'm grinning ear to ear I had so much fun with that conversation it's been an area that I've been absolutely fascinated with over the course of maybe 20 years now and um talking with somebody like Alina like I said earlier I think it just really humanizes this element of performance that we get all too caught up into uh when we're looking at these Paralympic athletes appreciate the heck out of everybody listening today if you have not had a chance head on over to Apple Podcasts and give this podcast a rating or review that means a heck of a lot to me personally when I see those reviews come in appreciate you guys listen and we will see you out on the trails you