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I get a list serve from Australian coach Steven Bennet at Oztrack.com. Recently it contained the following: "I recently read an article called "How does V02 evolve during the 800m?" by Hanon, Thomas, Chevalier, Gajer and Vandawalle. It is in edition 3/4 2002 of IAAF New Studies in Athletics. The researchers studied many physiological parameters during 800m race conditions. The athletes used were about 2min athletes. Their findings make interesting reading. The summary follows: Phase 1- During about the first 315m or around 45s that VO2 increased. Phase 2 - The next 215m up until about 535m VO2max was maintained. This was a total duration of just 33s. The furthest anyone in the study maintained V02max was 640m. Phase 3- V02 gradually decreased to reach an average of 83% of VO2max at the finish line. The average decrease was 20% (range 13-27%) The explanation for the dramatic change in Phase 3 was suggested to be hyperventilation, lowered blood pH, fatigue of respiratory muscles and a decrease in heart stroke volume. All of these factors contributed to result in the reduction of gas exchange with the blood. It is apparent that only 33s of 120s in the athletes tested was spent at V02max which is 27%. However the decline phase lasted an average of 43s which is 36% of the race." My questions are: Specifically why does VO2 fall off? I don't buy the respiratory fatigue argument because at the end of an 800m I'm breathing super-hard. Why would hyperventilation inhibit VO2? Why would a decrease in blood pH inhibit VO2 if running speed is still faster than VO2max pace? I can see cardiac output dropping a little if heart rate is maximal, but this is a huge fall off. Also, what does this imply about VO2max intervals? Does this mean if you do them too fast you'll actually spend less time at VO2max? |
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Bump |
| jtupper |
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Rather confusing. I wonder where they did the running -- treadmill or actually overground. If overground then I wonder what equipment was used to monitor VO2. When you get a drop in VO2 with continued hard work you would have to wonder if the breathing valves or face mask or whatever equipment they were collecting expired air with might have been leaking. I'd want to see minute ventilation, breathing frequency, tidal volume, respiratory exchange ratio, etc. Those could hold a key to what had happened, or what may have gone wrong. Also, did the subjects run at an even pace (60-60 fo reach half of the 2-minute effort). did they actually go at each inddividual's race pace? With equipment on that could be rough. However, When I did my dissertation with Olympic runners I collected expired air samples with them running on the track (drove beside them with a car and they breathed through a specially designed valve and collection equipment (actualy named "Daniels Valve")that offered little resistance. I had one runner who breathed over 220 liters per minute (he weighed only 153lbs). A current world record holder who was 6-3 and weighed 160 breathed less -- 186 liters per minute. Just goes to show you that how much you breathe can vary considerably. We did may track tests in this manner and I often had people run under 60 sec for th elast lap of a test (54 was the fastest we had for a last lap although a great foreigner I tested back then ran 3:04 for his last 4 laps of a 5 lap VO2max test. We never saw a drop off in VO2 in one test. We did over 200 tests that lasted 800 meters each and over 100 that lasted 2000 meters each -- both at altitude and at sea level. Never saw VE (minute ventilation) drop off and never heard of breathingmuscle fatigue among this caliber runner. I guess I must say I am puzzled by the findings and initially suspect the test equipment or something to do with the way things were done. I have seen many runners hold VO2max for several minutes, during a regular max test on a treadmill. Depending on how you measure VO2 you can get some fluctuations (for example if you take a 15 second measure and multiply that by 4 to get a minute value, and if that 15 sec volume of air has an extra breath in it (because you started the 15 sec collection with an expiration and ended it with an expiration) then the 1-minute value could be way high. Of course an immediately-following 15sec collection would now start with an inspiration and maybe end with one so this minute value would now be extremely low, giving an up an down effect.) A fault of coomputerized equipment is that you don't get to see the little things that take place and that make up the final answer that is so nicely printed out for you. The higher tech we go the more we seem to trust the results and it could often be just the opposite. By the way, in our tests on the track we found that VO2 is about 70% of max the first minute and hasn't even reached max by the middle of the second minute. Remember, if you make a collection from 1min to 2min, the answer reflects the 1/2 minute value not the 2minute value. Sorry if I haven't shed the proper light on this matter. Maybe I have provided some useful information based on our own tests. |
| chicorunningfool |
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jtupper: Why doesn't VO2 reach max the first lap and a half? What could you do to reach VO2 max sooner; would this help race performance? Could this have something to do with why the 2nd repeat is always easier then the first in workouts? |
| jtupper |
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Sorry I see 2 errors in my earlier post. I meant last 3 laps the guy ran just over 3 minutes (not last 4 laps). And toward the end the answer reflects the 1-1/2min value (rather than the 1/2 minute value as I printed) Sorry |
| JimFiore |
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Is the "driving beside with a car" like that pictured on page 43 of Running Formula? (And is that you driving or sitting on the hood?) ;-) |
| CarolinaRunner |
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No, there is NO way that jtupper is Jack Daniels. That huge post was all such common knowledge. It was exactly what I was about to say. He just got to it first. J Any plans for a new book? I've worn out my copy of Daniels' Running Formula |
| Frank Booth |
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In the same vein, if you will excuse the pun, I've been looking for a copy of _Oxygen Power_ for a couple of years. It never turns up in used book stores. Does anyone have a line of how I might get a copy? Thanks. |
| jtupper |
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So many questions, so little time. Fiore-- I'm sitter, can't trust me driving (or I don't trust anyone else collecting). Chico -- I encourage harder warmup (after the usual easy running and strides, instead of the usual quick short strides as the final thing, I encourage a 2-3 minute run at moderately hard intensity, then about 10min rest, then race). Makes the start of a race feel like the second rep. Doesn't work for all but sure is worth a try when it doesn't count too much(majority who try like it). Probaly are at VO2max sooner than expired air samples indicate; remember that expired air represents gas concentrations that are currently in the lungs and left the muscles awhile ago. Warmup too hard too close to the race and go into the race with a relatively elevated blood lactate. Somewhat elevated is good however, as in the case in a series of repeated workbouts. Carolina -- the book is being revised, with a few new things. I worry that some things will hack off serious runners and other things alienate beginners. Hopefully the appropriate people can ignore what doesn't apply. Booth -- you can get Oxygen Power from the publisher at 948 Walden Pond Lane, Cortland, NY 13045 |
| Phoenix |
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Two questions, one for JD and the other for FB: JD: Does heart rate have to reach max for VO2max to be reached? Is there a zone were HR and SV trade off to produce an identicle cardiac output at VO2max. If I run 1000 meter repeats at faster than 5k pace my HR hits 185 at the end when my max is 196--I can hold max HR for about 30 seconds before my legs quit. Your book predicts my VO2max at 74. Maybe my threshold just stinks. FB: Is there any truth to the idea that distance running ability is in large part determined by the mitochondrial DNA inherited from one's mother. (If your really FB you can answer this. My PhD advisor did post doc with JH at WashU while you were there.) |
| inquiring red dragon |
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JTD look through HADD, tell us what you think of this? |
| runfastr |
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Pheonix, My guess is your AT stinks as you put it. Something I have noticed about heart rates while training at VO2 max pace is that the more rested you are, the closer you will come to your max heart rate. Also the more fit we are aerobically allows us to get our heart rate up higher much sooner and maintain it there with much less cardiac creep.Chances are you won't see your max in a workout though because you have rest breaks in there. Also you won't come close to your max on the first repeat, you will be a lot closer on the last one though. If you aren't, then I suspect poor aerobic you may be over training or glycogen depleted. Also with respect to you statement about your VO2 max being 74, the chart in the book takes into account 3 variables to come up with that number. It's an average. All things being equal though, I believe you would have to add 3.5ml per kg just to sustain ourselves at rest, but jtupper could answer that better. Paul |
| JimFiore |
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JTD: On the book revision, have you considered making separate sidebars for advanced and beginning runners? I wrote an engineering text a few years ago and my publisher was struggling with the "How much detail is enough?" problem. We wanted to keep the schools at the higher end of the spectrum but not alienate those that didn't go quite so deep. We came up with the idea of "Extended Topic" sidebars. It made the detail-mongers happy and it was easy for the other folks to ignore. We stuck them at the end of each chapter but I can see it working within each chapter. BTW, one thing I really enjoyed about Running Formula was the elite athlete profiles. |
| JXZ |
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This is the whole message Date: Wed, 14 May 2003 04:20:54 GMT From: "Steve Bennett" Subject: Energy Systems & Efficiency I recently read an article called "How does V02 evolve during the 800m?" by Hanon, Thomas, Chevalier, Gajer and Vandawalle. It is in edition 3/4 2002 of IAAF New Studies in Athletics. The researchers studied many physiological parameters during 800m race conditions. The athletes used were about 2min athletes. Their findings make interesting reading. The summary follows: Phase 1- During about the first 315m or around 45s that VO2 increased. Phase 2 - The next 215m up until about 535m VO2max was maintained. This was a total duration of just 33s. The furthest anyone in the study maintained V02max was 640m. Phase 3- V02 gradually decreased to reach an average of 83% of VO2max at the finish line. The average decrease was 20% (range 13-27%) The explanation for the dramatic change in Phase 3 was suggested to be hyperventilation, lowered blood pH, fatigue of respiratory muscles and a decrease in heart stroke volume. All of these factors contributed to result in the reduction of gas exchange with the blood. It is apparent that only 33s of 120s in the athletes tested was spent at V02max which is 27%. However the decline phase lasted an average of 43s which is 36% of the race. The 800m race is run at an average pace which is well above the Maximal Aerobic Speed(MAS). In this study the average pace was 124% of Maximal Aerobic Speed. Even in the final phase in the last 25m the athletes speed was still an average of 112% of MAS. This emphasizes that the speed capacity is being provided to a great extent by the anaerobic system. In my view it is certainly worth working the V02max and improving it. But it seems that an athlete could improve VO2max and maybe not be able to sustain it for very long. It seems more desirable to be able to sustain it for longer or prolong the distance decline starts to occur. It is also apparent that athletes also need to fully develop their anaerobic systems since the speed is always going to be well above MAS even when in the final 25m. It is no point having a highly developed aerobic system and an under-developed anaerobic system. Running at any given speed during an 800m race will require the energy to maintain that speed to come from all of the bodies energy systems. At race pace mid race the athlete is not accelerating and all they have to do is maintain momentum, Fundamentally all this required is a certain magnitude of force being delivered to the ground. One extremely important aspect to have a long term view about is in developing the athletes efficiency at race pace. This is because with improved efficiency there will be a lower energy cost to run at race pace. This way whatever their energy systems will be able to provide in total will be able to result in a faster performance. A useful analogy may be it is no point supercharging a race car at great expense and ignore improving its weight, aerodynamics, tyre pressure, gearbox etc. The added problem with running is that training that may optimize energy system outputs may also have the undesirable effect of decreasing running efficiency. This can come about as the result of the natural shaping effect on efficiency that occurs from the athletes practising the running habit in a way that exhibits bad running form. Bad running form can easily occur in any athlete who has not worked directly on improving its maintenance. Most athletes when fatigued can easily lower their centre of gravity by having a more bent support leg, lowered hips, low knee lift, overstriding in attempts to maintain stride frequency, excessive rotation of torso, footstrike not straight, etc. The same session in one athlete may shape improved efficiency where in another underprepared athlete may impact to decrease efficiency eg Wilson Kipketer doing 20 x 200m in 26s regardless of rest between would tend to hold great form and make that pace look really easy. He would get slower if super tired because of loss of prime mover power but it would not be accompanied by overstriding, wobbling etc. However a common under conditioned athlete may do a similarly intense session and look like a fun runner after 5 reps and then practise progressive worsening loss of form for the next 15. They would be typically overstriding, twisting, low knee lift - obvious long contacts , straining etc. This athlete may finish the session proud and satisfied because they know that this speed session wll make them fitter i.e. it will improve their energy system outputs. The sad part is that performance in races may decrease due to the negative impact that this session may have on their effic! iency. People may argue that if the athlete improves in each session then the session must therefore be worthwhile. The flaw in this thinking is that the energy system adaptations that are happening may be of a short term nature. The improvement in efficiency is much more longer term. As is the damage to efficiency much more longer term. This is not the sort of thing that an athlete can detect "this season". However it is a fault that will have a great impact long term on athletes who train under coaching regimes that ignore the concept. No technical training will improve an athletes efficiency "today", try running on a treadmill a a certain speed and change your technique, you will not be able to impact on heart rate at all. This is because the effect of running form changes on efficiency is a very much slower changing adaptation than we used to. I think coaches & athletes enjoy the quickness of so many of the adaptations that we can bring about with training that we ignore some of the bigger slower ones. EFFICIENCY should targetted and underpin our training philosophies because it is this important area we compromize when we forget about it. The problem is athletes often try to run with a better technique and feel that it is not working and this is because it isn't. It is just like the first time someone shows you how to swing a golf club. It initially starts of feeling really "fake"and it is. But eventually it becomes the habit and is totally normal, this happens after much shaping and then it is effecti! ve. Efficiency is like this. Training short term (season by season) in the area of energy systems can be a long term disaster for the athlete. This is especially true if young athletes do not have programs that target predominantly the development of efficiency first so that good habits are in place. They could then later introduce higher levels of energy system focused training as they improve their tolerance to maintaining really good form under high levels of fatigue. regards Steve Bennett www.oztrack.com |
| jtupper |
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At your suggestion I read through the stuff you referred me to. Lots of good information and advice. The more you delve into this stuff the more you realize there is to learn. Always remenber that not all people are designed the same (thank goodness). And the level of inherent ability, as well as the commitment to train, both vary tremendously. Of course this is the reason that various approaches work better for different people. Hadd's information does a nice job of explaining some basic principles of training and that is what I like to preach as well. It is so tempting to see what the current champion is doing and figure that is the answer to everyone's needs. Lindgren did it his way, Ryun another way. Many people have said that Ryun could have been even better if he had done less of this and more of that, but I tend to think he did exactly what was best for him (even though it didn't work particularly well for many of his teammates, who were doing the same things). Not particularly correct to copy him in hopes of being like him -- first understand the principles and go from there. We also have a very different (mainly, scholastic-based) athletic system in this country. We don't necessarily have high school coaches who are concerned about the future performances of their runners, and they will not be coaching them after HS, so the long-term plan is a non-factor for most runners (especially if you want to consider what would be best from the time they start until peak years of performance). I try to take what I can from my research background (fortunately I can draw on personal research findings -- many of which I have not had time to yet publish), listen to other researchers and successful coaches and athletes and come up with a plan (that suits which runners best?). I am so fortunate to have studied in Sweden where I became friends with Bengt Saltin and Bertil Sjodin (pronounced close to Sherdeen) and had PO Astrand (pronounced Ohstrand) as a professor. Sjodin is a coach also so I have always liked his apporach to things. Dave Costill and Bengt Saltin and I have done research together, so I feel a certain attachment to these quality men. Add to that the many successful runners I have had the luxury of testing and watching train and I often just get confused as to what is the best thing to have runners do (the old the-more-you-know-the-more-you-don't-know rule). Throw into the mix the tremendous success of the East Africans and it is hard to figure what the real answer is. I try to look at other sports and how they train (not exclusively, but it must be done) and swimmers work really hard and a lot. We say we can't do that in running because of the trauma of landing shock -- too many injuries. But it is hard to compare these sports because the longest Olympic event in swimming is 15 minutes duration (have a 25k in world championships however)so we are just comparing with runners of 5k and shorter. No doubt fractional utilization is a big factor in distance success, which relies on good lactate clearance, but some people are better at more intense efforts. How often do we hear of a great 800 or miler who is gong to set the world on fire when he/she moves up to the 5k or longer. It may work for some, but for others it is not in the genes to make that move. No single answer. I hear from many HS coaches wondering how to best get ready for this season's cross country races. The situation is this -- there are some seniors, juniors, sophs and incoming freshmen (some have not yet taken a step of running). Our season is 9 weeks long and how should I train them to get the best out of them. Or I have this runner who really wants to get a scholarship to go to college, what training will make the best impression on the college coaches. Then it turns out this runner has no intention of becoming a great runner, just has a scolarship as a goal and once achieved, will do the least possible to maintain that money (and I cannot blame them, with the cost of college now). I paid $40 per quarter for tuition and paid $5 (per month) for my share of a house to live in during college. Usually ate ducks, deer, fish or whatever we could get to keep the food costs down. So at that cost you didn't need to impress anyone with a time in HS; just go where you wanted and see how it turns out. Plotting a long-term plan was a more reasonable option. Sorry, I could spend a lot of time about where we are and what might be the best way to solve running problems, but this is not the place -- takes too much time. Be a little careful when trying to evaluate what type of training will be best for you. If your relative times drop off as the distances increase it coudl mean one of two things -- you have not done the type of training that best influences longer-distance performances or you may be built to handle shorter events better. Then the question becomes -- do you increase your emphasis on your weakness (ignoring your inherent strength) in order to improve performance, or do you improve your strength to the extent that it pulls you along even in your weakness. again, we are not all the same. Even the psychology of it all is so important. I am convinced that I do better with people I personally recruit because I probably tend to recruit individuals with the type of personality that I like and feel comfortable with (not an earth-shaking deduction). So i have great success coaching some people and not as good with others. Enough said |
| jtupper |
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I agree whole heartedly about economy being the way to go for long term improvemnt (along with increased threshold). Most important example is in swimming where technique plays such an important role. We have tested swimmers on many occasions and can watch economy improve over the years. The great young swimmers have the aerobic capacity of the older, better swimmers, but can't match their performance because of weaker economy. This, of course raises the issue of doing more fast training at early ages. Your point about some being able to hold a pace with good technique and others not is important. That's why I like to include adequate recovery between faster type workbouts. Some feel that if 10X400 at 60 with 3 min rests is good then 10X400 at 60 with 1 min rests must be better. Couldn't be farther from the truth if you are interested in promotig efficient running. The short rests are OK if you can hold form doing them, but the important system involved may not be recovered so another system comes into play and that may be counter-productive in the overall scheme of things. It always come back to the question -- what is the purpose of this workout? If you can always answer that then all is well (especially if you do as designed and for the purpose designed). |
| Phoenix |
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JD: Does heart rate have to reach max for VO2max to be reached? Is there a zone were HR and SV trade off to produce an identicle cardiac output at VO2max. If I run 1000 meter repeats at faster than 5k pace my HR hits 185 at the end when my max is 196--I can hold max HR for about 30 seconds before my legs quit. Your book predicts my VO2max at 74. Maybe my threshold just stinks. Cardiac drift occurs from dehydration. What about the effects of decreasing blood pH on the cardiac acceleration independent of O2 demand. I'd appreciate your input here. I've asked these questions to exercise phys PhDs but they can't answer them. He who has the most data wins--in this case you. Thanks. |
| JE |
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jtupper: You make an excellent referance to swimmers and economy. All four of my children are swimmers.The two oldest, both girls have never displayed either speed nor endurance in other sports i.e. soccer/softball,however as swimmers they both have excellent technique which allows them to be fairly competative with top swimmers.My two youngest sons have both displayed speed and endurance in other sports while haveing excellent technique in swimming ,enabling them to be top performers. I am curious for runners how to recognize poor form and running economy. What drills,exercises to perform in order to maximize running economy. Thanks |
| jtupper |
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Typically max stroke volume is reached at about 60 or so % of VO2max, then HR continues up as does cardiac output. Certainly HR has a max and it is partly dependent upon the fact that the faster the heart beats, the less time there is for blood to flow through the coronary system, feeding the heart (that flow is pretty much limited to taking place during the relaxation phase of the heart beat). The heart takes care of itself if at all possible, and if the flow of oxygen through the coronary system is not up to its needs (remember, the heart muscle cannot go anaerbic) the coranary system senses a PO2 that is too low and in defense HR will slow down. This is a typical occurance at altitude where max HR is usually lower than is max HR at SL. The heart could care less about your performance desires and fends for itself under undue stress. I guess this could happen during some strenuous SL runs. Since I have not researched this specifically I am not certain. It makes sense however because it has been shown that some runners desaturate (arterial blood is not as fully saturated with O2 as is normal) when working hard. It is doubtful that when stroke volume drops (due to dehydration for example)that HR will pick up the slack at maximum work. At submax, yes, because this is the way to maintain cardiac output. As heat builds up and more blood is diverted to the skin for cooling, then submax HR picks up because the working muscles still want their share and now the skin demands more -- in this case cardiac output increases as well. Cardiology is not my specialty, so much of what I have to offer is from others with specific expertise (following questions that have come up in my own studies of runners). HR can be a tricky subject. For example many studies have been done on the treadmill (TM) and HR data from there transferred to overground running. That isn't always ideal because cooling is usually better overground and even though it may be cooler in the lab, lack of air movement can make your own micro-environment quite hot. Also, even though it costs more energy to run at the same speed overground, it doesn't necessarily come with a higher HR. |
| jtupper |
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Running economy is an interesting topic. It is not necessarly how you look running that determines how economical you are. I've tested some pretty bad looking runners with great economy, and some "pretty" runners with poor economy. Often a coach says, "I'm going to work on your efficiency," and means I am going to try to make you look like I think you should look running, rather than reducing your energy expenditure running. There are times when a bad arm swimg, for example, is the result of trying to balance an imbalance somewhere else, and changing that arm swimg may cost more energy. The real proof of improving economy is if you can get the same job done with less energy expenditure, regardless of how you look doing it. Some research suggests that getting stronger improves economy -- speed work, hill running, bounding, plyometrics, etc. Some people are genetically more economical than are others, but both can improve economy. Some runners get more economical the faster they run, others get less economical the faster they run. Usually the 800/1500 types are the former and the marathoners the latter, which makes sense since they are more economical at the speeds at which they train. Since economy is a function of growth and faster training it presents a problem for those who don't want to do anything but easy mileage during early years of running. In a sense you might say that skill is what needs attention when a beginner, and certainly some coaches approach beginners this way, maybe rightfully so. |
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