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New VO2 Max research (Read 1151 times)

Scout7


CPT Curmudgeon

    At least, according to this article.

     

    Personally, I don't really think this information is necessarily all that earth-shattering for most of us, and certainly won't change the way we train.

     

    But it'll get a rise out of spaniel, I'm sure.

      I was reading about this similar concept from a study by Samuele Marcora.  In the study, he was able to show through a 12 minute test that the "fatigue" and exhaustion associated with high output was mental rather than physical.

      To prove so, he had athletes ride a stationary bike and produce a high amount of wattage in a sustained environment for 12 minutes (put them through a VO2 max test), and after fatigue and minor rest, did a 10 second sprint cycle at a wattage in excess of what they did before.

      According to the study, (as I understand it), the athletes did not break down and collapse, they gave up (since they were able to exert more than their max).

       

      "Fatigue in endurance exercise is always voluntary and always occurs as a response to an intolerable level of suffering, or what exercise scientists call perceived effort.  The problem is never lactic acid buildup or muscle glycogen depletion or any other form of running out of gas.  These things happen, but they never become so extreme that they directly stop the muscles from working.  They merely force the brain to make a greater and greater effort to keep the muscles working at a desired level until this effort becomes so unpleasant that continuing no longer seems worth the agony." (From Iron War, by Matt Fitzgerald).

      2014 Goals:

      #1: Do what I can do. <DOING>

      #2: 365 Hours training <NOPE, INJURED>

       


      Interval Junkie --Nobby

        @KerCanDo70 - sounds like the brain knows your muscles are red-lining and encourages you to shut off the engine before damage is inflicted.  I'm not sure I'd take a pill that allowed me to completely ignore the perceived pain.

        2014 Goals:  sub-3 Marathon 

        Current Status 08/28: Slowly working back up from a pelvic stress fracture.  4mil distance PR w00t!


        Feeling the growl again

          Good to see Noakes and his students now bastardizing his own definition of the central governer -- which used to be an unconscious, innate, and instinctive mechanism of the brain that protected the body from self-destruction -- to now include conscious response to mind games around the effort structure of a test.

           

          If I really cared I could pull up quotes where he said you can't override the central governor, yet now in his own student's test that's exactly what they do to supposedly prove the brain is in control.

           

          Essentially it's a hoh-hum finding that, at some level, someone's mental toughness is going to dictate when they call it quits.  However, this has nothing at all to do with his original claim that the brain is the ultimate limiter of performance.  It's quite different.

           

          MTA:  IMHO the study was somewhat flawed, in that it seems that the decremental test is inherently advantaged since subjects don't go into the maximal stage with the inherent fatigue of the incremental test.  It would seem to me that some components affecting VO2max (like the heart) may not perform as well after an extended tiring phase as they would a quick ramp-to-max effort.

          "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

           

          sport jester


          Biomimeticist

            It always resorts to one question for me; Is it more efficient to try and optimize how much oxygen the body can process, or decrease the amount of oxygen the body needs?

            Experts said the world is flat

            Experts said that man would never fly

            Experts said we'd never go to the moon

             

            Name me one of those "experts"...

             

            History never remembers the name of experts; just the innovators who had the guts to challenge and prove the "experts" wrong


            I'm back!

              Essentially it's a hoh-hum finding that, at some level, someone's mental toughness is going to dictate when they call it quits.  However, this has nothing at all to do with his original claim that the brain is the ultimate limiter of performance.  It's quite different.

               

              I agree that it's not at all surprising, and doesn't really suggest any changes in training strategy. But what do you mean when you say it's quite different? 

               

              That the brain is involved in fatigue is no surprise. But if it is merely the agent of turning glycogen depletion, high lactate levels, etc., into cessation of running, is it really reasonable to say "the brain is the ultimate limiter of performance"? Is that what you mean, or something else?


              Feeling the growl again

                I agree that it's not at all surprising, and doesn't really suggest any changes in training strategy. But what do you mean when you say it's quite different? 

                 

                That the brain is involved in fatigue is no surprise. But if it is merely the agent of turning glycogen depletion, high lactate levels, etc., into cessation of running, is it really reasonable to say "the brain is the ultimate limiter of performance"? Is that what you mean, or something else?

                 

                If you go back, Noakes' original assertion with the CG model is that subconscious protective mechanisms in the brain are the very basis for the limits of performance.  He has overtly stated that the focus on aerobic conditioning is incorrect and it's really the brain which is the major contributor to the limits on performance.

                 

                When one use the word "ultimate" it becomes, admittedly, a matter of definition.  If by "ultimate" you mean that the toughness to handle a higher perceived effort and take 5sec off at the end of a 5K, then sure.  I'll go with that.  However, that's not what Noakes has been selling.  He's said that max O2 uptake...glycogen depletion...lactate threshold and the peak speed of aerobic metabolism....none of this matters, in the end it's training the brain that matters. (So now we get into asking why easy runs make you faster etc...all of which I've asked Noakes and none of which he could explain with any satisfaction.)

                 

                If you really take Noakes' definition of the CG at face value, the only thing that separates a 20min 5Ker from a 15min 5Ker is their brain's CG set point...not aerobic conditioning.  Both athletes have the same potential if only the slower one set their brain better.

                 

                Having sparred directly with Noakes' on this, his logic becomes annoyingly circuitous as he tries to defend himself.  In one post "you can never override the CG", just a post or two later "I overcame the CG several times myself during Comrades", then when you point out the contradiction to him "Oh, I was mistaken, you can never override the CG".  You try to push why aerobic conditioning far below max levels improves performance, and point out that it is really aerobic conditioning then making the difference and not some brain set-point, and he gets inconsistent and cannot explain the difference.

                 

                You are entirely correct.  That the brain is involved in fatigue is not very surprising.  However, to say the biochemical metabolic processes we know to be important are not, and that instead a mysterious brain mechanism -- of which no structural, biological, biochemical, or other direct evidence has ever been produced -- is #1, IS surprising.

                 

                IMHO, fitness determines O2 uptake...as effort increases the brain is going to interpret these effort signals, of which all proficient runners are aware and attunted to.  At some level, your "toughness", or willingness to push to extreme effort levels, is going to determine your finishing time.  However, the difference between a non-tough person and a super-tough person over typical race differences will be relatively small.  The "ultimate" factor -- the one which will make you 2:30 marathoner instead of 3:00 -- is aerobic fitness...."toughness" may get you from 2:33 to 2:30 at the end.

                 

                So I hope this was clear...Noakes' position has been that the brain is the ultimate -- ie primary -- determiner of running speed, discounting the magnitude of other factors.  The bulk of evidence -- direct evidence, which Noakes still lacks -- points to aerobic fitness.  Toughness may get you on the podium but it's not going to put you in the lead pack to begin with.

                 

                Having read more articles by Noakes and his students than I care to admit...what really annoys me is the departure from the practice of science.  Most science starts with evidence...develops a hypothesis...then tests to either prove or disprove this hypothesis.  Noakes started with no evidence...formed a full model out of not much more than thin air...then has proceeded to conduct years of research which have produced no direct evidence to support his model, yet passes off as proven fact an unproven model.  When I've read the discussion/conclusion sections of the papers, they consistently make long leaps of logic to connect the results back to the model, rather then tying a concise, data-driven relationship back to the root hypothesis.  In other words, he has invested his career in the model and will pretty much fit any data produced back to the model in some way.  I was very confused how the logic all fit together until I actually corresponded with him...and realized that he could not put the chain together himself in a logical and consistent fashion.

                 

                 IMHO it's an example of someone who has sold themself to an idea, and will follow it no matter what the data says.  Those of us without a dog in the fight can fit both pieces (aerobic and brain) together.  Noakes, however, has invested himself in brain being #1 and has lost objectivity.  Do some Journal of Exercise Physiology searching on the editorial threads following a few of his articles...the attitude of some of his peers towards Noakes' writings is enlightening.

                "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

                 

                  I am not an expert or a scientist, but I thought that Noakes' claim was weaker: only that the feeling of fatigue is not due to the collapse of any one physiological system, but is a feeling produced by the brain in response to physiological stress as a protector of the body.

                   

                  The suggestion is not that we can overcome this feeling (override the CG) through toughness, but that through familiarity with the limits of certain systems, the brain allows them to run closer to their actual limits. What we are doing in training is two things, for Noakes: 1) improving the base physiology so that our physiological limits are higher (this is the classical theory) and 2) training the brain to allow the body to run more closely to its limits before producing the fatigue feeling. This "training" is much less about being mentally tough and more about habituating the body and the brain to certain physiological states.

                   

                  Traditional physiological models are unable to explain fatigue--they can only talk about the collapse of certain physical systems. Noakes' theory is an attempt to remedy this and to explain why fatigue comes at us wholesale (it is produced by the brain in response to certain physiological stimuli) instead of the body simply "failing" when a physiological limit is reached.

                   

                  Spaniel, I know that you are a scientist, and I trust your take on Noakes as a scientist. If Noakes made the claim that aerobic development or physiological development was irrelevant and that the difference between a 20min 5k and a 15min 5k only boiled down to the brain, then I think he misinterprets his own theory. There is a stronger version of this theory that would not make such reductive claims. This version of the theory is an attempt to explore the relation between subjective feelings of fatigue and physiological limits by looking at the way in which the brain synthesizes information subconsciously.


                  I'm back!

                    However, that's not what Noakes has been selling.  He's said that max O2 uptake...glycogen depletion...lactate threshold and the peak speed of aerobic metabolism....none of this matters, in the end it's training the brain that matters. (So now we get into asking why easy runs make you faster etc...all of which I've asked Noakes and none of which he could explain with any satisfaction.)

                     

                    If you really take Noakes' definition of the CG at face value, the only thing that separates a 20min 5Ker from a 15min 5Ker is their brain's CG set point...not aerobic conditioning.  Both athletes have the same potential if only the slower one set their brain better. 

                     

                    I have a hard time believing that's what Noakes really thinks. That's not what I got from Lore of Running. In fact he specifically refers to things like a "glycostat" by which the brain registers blood sugar level, and I'm sure he has mentioned similar sensors for lactate etc. None of which is controversial. Of course the brainstem monitors such things, and regulates behavior based on them. 

                     

                    You are entirely correct.  That the brain is involved in fatigue is not very surprising.  However, to say the biochemical metabolic processes we know to be important are not, and that instead a mysterious brain mechanism -- of which no structural, biological, biochemical, or other direct evidence has ever been produced -- is #1, IS surprising. 

                     

                    I don't think the brain mechanism is at all mysterious. I'm not a brainstem expert, but I'm sure those circuits are in there somewhere, maybe also in the hypothalamus. But all they do is detect physiological state and regulate behavior based on that. I will grant that the emphasis Noakes puts on the brain part seems to suggest that there is some important conclusion to be drawn from this idea -- but what that conclusion is supposed to be, other than that fatigue is not a local, purely muscular phenomenon -- which I agree with -- I've never been quite clear on.

                     

                     Having read more articles by Noakes and his students than I care to admit...what really annoys me is the departure from the practice of science.  Most science starts with evidence...develops a hypothesis...then tests to either prove or disprove this hypothesis.  Noakes started with no evidence...formed a full model out of not much more than thin air...

                     

                     

                    What bothers me is that he doesn't even have anything I can identify as a model. His statements seem either obvious or meaningless. However, you've obviously read far more Noakes than I have.

                     

                     

                    I am not an expert or a scientist, but I thought that Noakes' claim was weaker: only that the feeling of fatigue is not due to the collapse of any one physiological system, but is a feeling produced by the brain in response to physiological stress as a protector of the body. 

                     

                    I'm certainly not an expert here either, though I did do a postdoc in computational neuroscience.

                     

                     The suggestion is not that we can overcome this feeling (override the CG) through toughness, but that through familiarity with the limits of certain systems, the brain allows them to run closer to their actual limits. What we are doing in training is two things, for Noakes: 1) improving the base physiology so that our physiological limits are higher (this is the classical theory) and 2) training the brain to allow the body to run more closely to its limits before producing the fatigue feeling. This "training" is much less about being mentally tough and more about habituating the body and the brain to certain physiological states. 

                     

                    That's basically my reading of Noakes, from Lore of Running.


                    Feeling the growl again

                      bhearn/Jeff,

                       

                      If what is in Lore was the be-all, end-all of it, my opinion may be different.  I'm too far past caring to listen to Noakes to search and look up links to all the information driving my opinions.  I'm sorry if this is confusing to understanding my position.

                       

                      The frustrating part is as the three of us try to understand exactly what his position was....this was my experience with him.  It shifted depending on the quesition, to the point of being inconsistent with prior statements.  As I indicated, his logic is inconsistent especially when questionable points in it are pushed for harder confirmation.  It's easy to agree with his points on the surface but when you push deeper, that's where the inconsistencies start.  I'll point out that he and SJ have gotten along famously, if that says something.

                       

                      bhearn, you kind of hit on it when you say "his statements are either obvious or meaningless".  When I pushed on the apparently meaningless parts to derive meaning, this is when the issues started.  To him, they are meaningful but the logic did not follow.

                       

                      At the base of it all, any brain-related governor would start to kick in at the point when there is some stressor on the brain/body so severe that a protective mechanism would need to kick in.  It would seem reasonable to say that this is at or near a certain perceived effort that takes place within a relatively narrow performance range.  In other words, this brain mechanism is nor responsible for someone running an 18min vs a 15min 5K....a 15:10 vs a 14:59, perhaps.  I see nothing "ultimate" about the last few seconds off a race time....the "ultimate" determinate is that with the greatest magnitude of effect, which would be aerobic conditioning, for anything over 800m.  I'm sure if you look around you can find some quotes from Noakes poo-pooing the importance of aerobic conditioning (as the article originating this thread alluded).

                       

                      Scout, are you happy yet?  If you want a bigger rise you'll have to send your mom, I'm chuck out of energy to invest in this further.

                      "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

                       


                      Feeling the growl again

                         

                         

                        "Fatigue in endurance exercise is always voluntary and always occurs as a response to an intolerable level of suffering, or what exercise scientists call perceived effort.  The problem is never lactic acid buildup or muscle glycogen depletion or any other form of running out of gas.  These things happen, but they never become so extreme that they directly stop the muscles from working.  They merely force the brain to make a greater and greater effort to keep the muscles working at a desired level until this effort becomes so unpleasant that continuing no longer seems worth the agony." (From Iron War, by Matt Fitzgerald).

                         

                        This definition only works within a certain performance bandwidth.  To say that a 18min 5K runner only fails to run a 15min 5K due to voluntarily giving up is silly.  Yes, as one reaches the limits of their ability, "toughness", or willingness to take on the next level of fatigue, will become meaningful.  But this is always incremental in magnitude compared to the performance difference driven by aerobic conditioning.

                        "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

                         


                          At the base of it all, any brain-related governor would start to kick in at the point when there is some stressor on the brain/body so severe that a protective mechanism would need to kick in.  It would seem reasonable to say that this is at or near a certain perceived effort that takes place within a relatively narrow performance range.

                           

                          Not to keep this going, but as I understand it "perceived effort" is the brain related governor. It's not that the governor switches on at a certain effort, but instead that the feeling of fatigue or effort is itself the effect of the governor.

                           

                          I think these governor "set points" which may be genetic more than trained could tell us something about the difference between a guy like Hall and your standard 2:15 marathoner. Though he may be equally trained [impossible to measure] Hall's brain--through training or genetics--may allow him to run closer to his physiological limits without the feeling of fatigue.

                           

                          I understand this is totally speculative, but I imagine that as brain science develops and we get a better picture of brain states associated with fatigue, we might reach a point where we could test the theory.


                          Just a dude.

                            I hesitate to comment here because I am mostly ignorant.

                             

                            I do have the perspective of a runner who was once pretty good, then stopped for a long time, and am now coming back.

                             

                            A lot of my thinking is still left over from when I was able to click off 6 minute miles without much effort. Often I look at things from the perspective of a 15 minute 5k runner, not a 20 minute 5k runner.

                             

                            But then when I am out running, I start to run low 7 minute miles and my brain panics. I can be breathing easily. My legs would feel ok. My form is good. But everything is moving so fast that the brain freaks out and tells me to slow down. All the pushing I have to do to maintain that pace is mental.

                             

                            Once I push through that a few times, my brain accepts that 7:30 miles are ok... And only starts to panic at 7s. It's like the front of my brain knows that 7s are perfectly doable, and should even be easy, but the back of my brain is convinced that I am seconds away from passing out and dying.

                             

                            Now, could I go out and just shut off my brain and run 8 miles at 6 minute mile pace like I used to be able to do easily? No way. But I do spend some thinking about how I need to work on the mental part of running faster. Workouts like Fartleks and tempos really help me mentally get to those faster times. I work a lot on not watching my time as I run and just trying to be smooth and efficient.

                             

                            (I hope that was on topic... Wink Wink

                             

                            -Kelly

                            Getting back in shape... Just need it to be a skinnier shape... 

                              I hesitate to comment here because I am mostly ignorant.

                               

                              I do have the perspective of a runner who was once pretty good, then stopped for a long time, and am now coming back.

                               

                              A lot of my thinking is still left over from when I was able to click off 6 minute miles without much effort. Often I look at things from the perspective of a 15 minute 5k runner, not a 20 minute 5k runner.

                               

                              But then when I am out running, I start to run low 7 minute miles and my brain panics. I can be breathing easily. My legs would feel ok. My form is good. But everything is moving so fast that the brain freaks out and tells me to slow down. All the pushing I have to do to maintain that pace is mental.

                               

                              Once I push through that a few times, my brain accepts that 7:30 miles are ok... And only starts to panic at 7s. It's like the front of my brain knows that 7s are perfectly doable, and should even be easy, but the back of my brain is convinced that I am seconds away from passing out and dying.

                               

                              Now, could I go out and just shut off my brain and run 8 miles at 6 minute mile pace like I used to be able to do easily? No way. But I do spend some thinking about how I need to work on the mental part of running faster. Workouts like Fartleks and tempos really help me mentally get to those faster times. I work a lot on not watching my time as I run and just trying to be smooth and efficient.

                               

                              (I hope that was on topic... Wink Wink

                               

                              -Kelly

                               

                              All of this is good and reasonable. I think what you describe is really important for all runners--some of what we think of as fatigue is really fear and unfamiliarity, and working through that is a key to taking the next step in racing.

                               

                              However, I think what Noakes is talking about has more to do with training the brain as an organ rather than working on the mental aspect as you describe here. Conflating these, I think, is at the heart of the difficulty in understanding Noakes' thesis.

                               

                              We train the brain at two levels: through conscious attention, mentally, (this is what you are talking about Kelly) and also, physiologically, just as we train the other organs and muscles in the body. Noakes' point (I think) has more to do with the second form of brain training. If he's right, our training has physiological effects on the brain that help it to regulate effort. Through training we shift values like VO2max, Lactic Threshold, muscle strength, etc. but we also produce effects on the brain that allow it to distinguish between truly life-threatening effort and a simple jog. His idea is that the brain has to "learn" this difference by undergoing physiological changes in training that then affect the extent to which it regulates effort through the subjective feeling of fatigue, and that part of what we are doing in training is teaching this.

                               

                              A further question is the extent to which we can alter the point of fatigue through conscious practices like the ones you are talking about: visualization and relaxation (and less conscious ones like competing and running in a group,) allowing the brain to let us reach closer to our physiological limits without fatigue.

                               

                              It seems clear to me that this is possible. A great deal of the art of coaching, seems to me, is actually convincing the athlete to let down his defenses and run. The best coaches do this through a combination of conscious mental practice and workout sessions that work physiologically to allow the brain subconsciously to familiarize itself with certain efforts and paces.

                               

                              As for the experimental science behind this, I understand spaniel's skepticism. The sort of science that would distinguish a "classic physiological effect" from a "brain-regulated effect" is very hard to do with any level of accuracy or control because quite frankly we lack the technology to explore these questions in a laboratory. Further, I think [here's me talking out my ass] that these two different paradigms of thinking about what's happening in the body are both overly reductive. Most likely what is "really happening" is an ongoing interaction between brain regulation and physiological feedback through certain hormones, etc.

                               

                              The good news is that as runners and coaches, we don't necessarily need to understand the ins and outs of all of this. We know, for example, that visualization and relaxation are important elements of racing. We know that runners do better when they jog the course before a race. We know that the training effect usually doesn't come incrementally but in "breakthroughs" and "plateaus" that often have as much to do with psychology than physiology.

                               

                              Finally, we know there are no secrets--there's just the glorious grind.


                              Feeling the growl again

                                \

                                I think these governor "set points" which may be genetic more than trained could tell us something about the difference between a guy like Hall and your standard 2:15 marathoner. Though he may be equally trained [impossible to measure] Hall's brain--through training or genetics--may allow him to run closer to his physiological limits without the feeling of fatigue.

                                 

                                 

                                I think I'd really need to see some solid evidence to buy into the assertion that someone like Hall is so much faster than 2:15 is just because they can work their body harder (ie not feel fatigued).  

                                "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

                                 

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