Lactate Analyzers

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Lactate Testing - Some Questions

Some Basics

What is Lactate?
Lactate is an organic molecule. In past versions of this page we have said it was a carbohydrate. It is technically not a carbohydrate but an ion with a negative charge or an anion. Its chemical formula is C3H5O3-. It is found in every cell in the body; it is on the skin and in sweat and saliva. It is harmless.

What is Lactic Acid?
Lactic acid is an organic molecule. Its chemical formula is C3H6O3 and has the same ratio of carbon, hydrogen and oxygen as carbohydrates but it is technically not a carbohydrate. It is rarely found in the body. It is harmless. Many people believe wrongly that lactic acid occurs in the muscles after hard exercise, causing a burning sensation. This is not true.  Actually, if lactic acid is produced in the body, it breaks down almost immediately into lactate and hydrogen ions. What persists in the body is lactate. Notice the chemical formulas are very similar. A very kindly and professional chemist suggested some of the wording in these definitions.

Does lactate or lactic acid have anything to do with breast milk or lactation? What about lactose intolerance?
No. Lactic acid was discovered in sour milk in the late 1700's. Because it was discovered in milk, it was given the name lactic acid. But that is it. There is no connection to lactation or lactose intolerance or a type of milk called Lactaid.

What is glucose?
Glucose is a simple sugar (monosaccharide) and an important carbohydrate in both animal and plant metabolism. Its chemical formula is C6H12O6. Cells use glucose as a source of energy and a metabolic intermediate. Glucose is one of the main products of photosynthesis and starts cellular respiration (this first part was taken from Wikipedia.) Now look at the chemical formula and the one for lactic acid. Glucose is exactly double. This relationship is why lactate is important. Glucose is one of the main fuels in our bodies for energy and when it is broken down it ends up as two lactates. For those of you who are chemistry wiz's, you know we skipped something and we will now get to it.

What is pyruvate?
Pyruvate is an organic molecule used for energy. Its chemical formula is C3H3O3- and sometimes appears as pyruvic acid C3H4O3. It is found in every cell in the body, but in much smaller quantities than lactate. It seldom persists and is either converted into lactate or used for energy. Notice that the pyruvate chemical formula is similar to the formula for lactate. It differs by two hydrogen ions.

What is glycogen?
Glycogen is just a string of glucose molecules. So if you hear the term that someone is glycogen-depleted or low on glycogen it just means that there is little glucose in their muscles. If there is little glycogen in the muscles then glucose cannot break down to form lactate and this form of energy production is cut off.

Do you have to know chemistry to use lactate testing?
No, we just showed the chemical formulas to demonstrate that these molecules are all related. All the coach or athlete has to know is that lactate, glucose, pyruvate and glycogen are changed during exercise and that they turn back and forth into each other. Actually lactic acid is not part of anything but a high percentage of the coaches and athletes think it is. Many will refer to a lactic acid threshold instead of a lactate threshold.  Actually, there is no such thing as a lactic acid threshold. To understand all this better go over the energy generating processes on our CD-ROM or a briefer version in our triathlon section.

So where does lactate come from?
Glucose is used to produce energy. The process does not use any oxygen. Thus, the process is call anaerobic or not aerobic because it does not use air or oxygen. This anaerobic process has a name which is glycolysis. Remember glycogen from above. That supplies the "glyco" part and "lysis" is just the suffix from the Greek which means to break down as in analysis or catalysis or paralysis or dialysis. Well glycolysis breaks down glucose and produces energy and lactate. It really produces 2 pyruvates but the 2 pyruvate immediately turns into 2 lactates. An important part is that this process does not need oxygen and is called anaerobic. For those who don't mind chemistry here is the process that produces lactate.

glycolysis to lactate


The chart above is not quite accurate. Of the 4 H+ two of them are free hydrogen ions but two come from a molecule called nadh.

Are there other anaerobic processes that produce energy?
Yes, another important process is the creatine phosphate process and there are other minor ones.

Where do you measure lactate?
This could be a very long answer. It would be ideal if you could measure lactate in the muscle but that is impossible for normal testing. What one is trying to measure is not lactate but anaerobic metabolism in glycolysis. The amount of lactate produced is a surrogate for this. Most of the pyruvate at low levels never turns into lactate but is used by the muscle as fuel for aerobic metabolism. The pyruvate not used turns into lactate and then it is mostly used by the current muscle but can drift out into the blood stream. As energy intensity picks up more lactate is produced and more appears in the blood stream. So it is blood lactate or the lactate that leaves the cell and ends up in the blood that one measures.

There are lots of places where you can measure the lactate in blood. If you have been to the doctor you are familiar with the technician taking blood from a vein in the arm. That is venous blood. It is possible to use venous blood but that requires a trained specialist. In the 1950's it was shown that lactate in arterial blood is a much better indicator of physical activity than venous blood. But only trained doctors should be attempting to get arterial blood so this is very impractical. It turns out that the blood in the ear lobe is close to arterial blood and the finger tips are also ok. That is why most top level exercise physiologists in Europe will use blood from the ear lobe but this takes someone with practice. On our CD-ROM there are instructions on how to take blood from the ear lobe. The easiest place to take blood is from the finger tip and this is the most common place.

What type of blood is preferred?
By this we mean do you want to take whole blood or spin it down and take plasma. In theory plasma is better because the concentration of lactate in the plasma is much closer to the concentration in the muscles. But plasma was very difficult to get so in the early 1980's laboratory instruments were able to more easily use whole blood than plasma and ever since the standard in journal articles and with testing athletes has been whole blood. But plasma is a more accurate estimate of the muscle lactate.

One time we were at a rowing conference and one of the sports scientists complained about the Accusport analyzer we were selling because it essentially measured plasma lactate and did not measure whole blood. Our competitor was telling potential customers that the analyzer was inferior to theirs because it did not measure whole blood. There was two things wrong with this. First, the plasma was the better measure and second the other portable analyzer also measured plasma. But the average coach and sports scientist did not know this so the competitor falsely disparaged the Accusport which was a very accurate instrument.

Why is plasma preferred but whole blood ok for lactate?
The reason plasma is preferred is as stated above because it is in close equilibrium with the muscles. Whole blood is composed of plasma and red blood cells (rbc's.) The red blood cells are negatively charged and because of this the lactate which is a negative anion is repelled as two negative charges repel each other just as in a magnet. The lactate levels in the rbc's is much lower than the plasma so the mixture of the plasma and the rbc's which forms whole blood is also lower than the plasma and the lactate levels in the muscles. Red blood cells make up on average about 40% of the volume of blood. Despite this, whole blood is the medium that most use in lactate testing. All portable lactate analyzers measure the plasma lactate but provide an estimate of the whole blood value as its basic reading. The Accusport or Accutrend Lactate and now the Accutrend Plus is the only analyzer that provides a true plasma reading. It has an option that estimates the whole blood lactate and this is what most people use.

This does not mean that the current portable blood lactate analyzers are not useful. They are extremely accurate and useful to the coach or athlete that is trying to understand what is happening with the body's response to training. They estimate whole blood lactates and they do this very accurately and whole blood lactate is highly correlated with the plasma lactate value.

Some Essentials

Why measure thresholds?
Researchers have identified three factors that are highly correlated with performance in endurance sports. These are

  • V02 max
  • Lactate Threshold
  • Economy of Movement

Of these three the most trainable is the lactate threshold. So most endurance training should be focused on improving this factor. There are many related concepts to the lactate threshold and all involve a transition. Some are more important than others. This section discusses these transitions and whether an endurance athlete should measure them. And if the athlete should, how best to do it.
What is the anaerobic threshold?
The anaerobic threshold is a term coined in 1964 by Karl Wasserman when he used V02 measurements to show a change in the gas curve that seemed to correspond with an increase in lactate in the blood. At a point on the curve, C02 increased more than he expected. The subjects were producing more lactate than the muscles could consume; the buffering of this lactate was thought to cause the observed increase in C02. Wasserman called this the anaerobic threshold because it was thought that the body was suddenly transitioning to anaerobic metabolism. Some other researchers later pointed out that while excess lactate was being produced and it appeared in the blood stream, the body was in a steady state. Oxygen was still being used in ever greater amounts.  So while the lactate in the blood indicated a somewhat greater involvement of the anaerobic system, and C02 increased confirming this, aerobic metabolism was still the main source of energy, was still increasing and was not near maximum.
(It should be noted that the term anaerobic threshold has in recent years been re-defined to mean a much higher effort level:  the maximum level that an athlete can maintain for a long time without causing lactate to rise sharply.) See What is the lactate threshold? just below.

More on Wasserman's study.
Here are two quotes from the original Wasserman study. First,

"The onset of anaerobic metabolism during exercise can thus be detected in three ways: (1) as an increase in the lactate concentration in blood, (2) as a decrease in arterial blood bicarbonate and pH and (3) as an increase in the respiratory gas exchange ratio (R)."

and second,

"Thus, it is possible for the examiner to detect the threshold of anaerobic metabolism during the work test"

He then went on and used the specific term, "anaerobic threshold" because he believed that this was where the anaerobic system took over.   He was wrong about this and that is what science is about. Discoveries like Wasserman's are what move the ball along but unfortunately his idea of a major abrupt change in anaerobic metabolism was wrong. This misconception persists till today with many people. Anaerobic metabolism occurs before this so-called threshold point, and aerobic metabolism continues after it.  And the place on the gas curve he pointed out is not an important point for training for endurance sports. Wasserman was not the first to find this point:  Hollmann had published the same information in 1959, but Hollmann’s work was in German and not known in most of the world at that time. Both Hollmann and Wasserman are still alive. Hollmann was head of the German Sports Academy where Alois Mader worked and Jan Olbrecht got his degree. And who are these people? They figured out how the body mixes aerobic and anaerobic metabolism and how to use this information to train athletes.  There is more information about them and their discoveries below. We also have a more detailed discussion on this topic on our thresholds page especially on how to train the thresholds. But before you do that, you should read about the term, "lactate threshold."

What is the lactate threshold?
Originally what was called the anaerobic threshold point coincided exactly or approximately with the point where blood lactate rose over baseline levels. Other researchers then re-named this point where the lactate rises, as the "lactate threshold". In fact there is no real threshold here, nor has any real transition taken place; still, two different researchers used the term “threshold” for these points.

The curve below is a typical lactate curve. Several measurements have been taken as well as a resting lactate. Notice that the lactate remains close to the resting rate for several measurements even though the muscles are producing anaerobic energy, and producing pyruvate and lactate. When the lactate starts to rise, this means some of the lactate being produced is entering the bloodstream. It is hard to pinpoint a specific place on the curve where the rise really starts. There are no gas measurements here so there are no V02 and C02 measurements to find the ventilatory threshold, which is what the original anaerobic threshold is now called. We will ask a question of the reader:  where does the lactate curve start to rise? The problem with getting an acceptable answer to this question has taken up a lot of the time of many researchers. We will take the point of view that the answer doesn't matter, even if there is a correct one. So the athlete should not worry about it.

lactate curve for recreational runner

An athlete could continue to increase his intensity above this point where the curve starts to rise and still be in a steady state in terms of lactate in the blood. A steady state means that if the athlete continues at that pace, most physiological measures will remain constant.  Lactate, oxygen consumption, heart rate, perceived exertion will stay fairly constant just at slightly higher level. At 9 mph, this athlete’s lactate is now a little higher, but it is still in a steady state:  he can maintain this pace for a long time without his lactate changing.

At some point for every athlete, there is a higher effort level, where lactate is no longer in a steady state. Trying to continue indefinitely at this pace will not be possible:  lactate rises sharply and the athlete has to stop.  This truly represents a transition where the muscles eventually have to cease contraction – a true threshold. So this higher level became known as the anaerobic threshold even though Wassermann had named the lower effort level where lactate first starts to rise, the anaerobic threshold. The earlier concept was re-named the aerobic threshold by some, though there is no reason why it should be designated as aerobic. Aerobic metabolism does not stop there, nor does it begin there, nor does it change in any significant way there. The common name for this lower level when it is determined by gas measurements is the ventilatory threshold.

Beyond the higher level, lactate increases steadily, so this higher level is more appropriately referred to as the lactate threshold (even though this had also been used for the lower level). Since this was the effort level most useful in predicting performance, this term stuck, at least to the present time.  Most people use the term lactate threshold to mean the second and higher level.  This terminology is a mess since most people use the term anaerobic threshold and lactate threshold to mean the same thing, and it is different from the original use. They use it for the higher point, which is a true transition. Below is a set of curves depicting steady-state runs and two after the runner reaches a point where the runs are no longer steady-state.

steady states runs and lactate levels

In the spirit of compromise some researchers want to use the term "lactate threshold" to mean two things, the lower level and the higher level. They want to rename these points Lactate Thresholdaerobic and Lactate Thresholdanaerobic They want to call the range in between the two points the aerobic-anaerobic transition. Unfortunately none of these terms makes sense. There is only one transition and that is at the higher effort point. The transition has nothing to do with any changes to or from aerobic or anaerobic metabolism. At both points, the lower point and the higher point, there is a gradual increase in both energy systems and neither point has anything to do with training effects. The transition at the higher level has to do with the capacity of the cells to utilize lactate as a fuel versus the rate at which it is being produced. It has nothing to do with one system producing more and the other system producing less or even staying still. Both are increasing at the threshold. It is more like a pump in your basement trying to empty water that is coming in due to heavy rains. If the rains are too heavy, eventually the best pump will be overwhelmed and the basement will flood. So the transition at the higher threshold has more to do with the relative strength of the two energy systems than any transition of either one to some new state. At both points aerobic and anaerobic energy are increasing. There is no transition in the energy systems other than each getting a little bit higher. Using terminology that implies that there is some change going on in either system has only led to confusion. We have a more detailed discussion on this topic on our lactate threshold page and thresholds page especially on how to train the thresholds.

So who is Alois Mader?
Mader has done more than anyone else to focus attention on lactate testing as a possible way to assess athletic performance. His later findings on how energy metabolism works in humans, largely through the various uses of lactate, have largely been ignored. In the late 1960's and early 1970's Mader worked for the East German sports machine. He noticed that when his athletes would run at a pace that corresponded to the production of 4 mmol/l of lactate in their blood, they could seemingly run for a long time, and their lactate did not increase above the 4 mmol/l level. When they increased their pace they were forced to stop and the lactate had risen to much higher levels. He then postulated that the anaerobic threshold was 4 mmol/l. When Mader escaped from East Germany and went to The Sports School at Cologne, he published his results and immediately popularized lactate testing as a means of optimizing performance in athletes.

Rivals were quick to point out that the lactate level at which this maximum lactate pace took place varied considerably among individuals from as low as 2.5 mmol/l to as high as 6 or 7 mmol/l and that it varied by sport. Also a couple of his students and a local swimming coach went off to conquer the swimming world using the 4 mmol/l concept. And they failed. But in the meantime Mader solved the problem and in the process developed his model of energy metabolism which explains how the muscles decide to produce energy, how much aerobically versus anaerobically. He found that the key to energy production was in the anaerobic system and not just in the aerobic system as most sports physiologists believe.

So who is Jan Olbrecht?
Jan was one of Mader's student's who failed to conquer the swimming world. He came back to Cologne, completed his doctorate and validated Mader's ideas for swimming. He has been using them ever since to train athletes and the athletes he helps train have won over 50 Olympic and World Championship medals including the world record holder of the Ironman triathlon. He wrote the book, The Science of Winning, that explains his methods. His ideas form the basis for this web site and most of the CD-ROM, The Secrets of Lactate. The book's focus is on swimming but two top triathlon coaches rate this book as the best book on training for triathletes and it is popular with rowing and skiing coaches as well as swimming coaches. Jan recently presented at the First World Congress of Science in the Triathlon in Alicante, Spain.

What is OBLA?
Early on several sports scientists experimented with the 4 mmol/l level and the training of athletes. Two, Bertil Sjödin, from Sweden, and Ira Jacobs, a Canadian graduate student working with Sjödin, did some studies on the correlation between the pace at 4 mmol/l and running performance and published their results starting in 1981. The title of the first article they wrote was "Onset of Blood Lactate Accumulation and Marathon Running Performance." This quickly became OBLA and marathon performance in common discussions and since that time the 4mmol/l level has been associated with OBLA as well as the anaerobic threshold. Before them in 1979 in an article by Farrell and several others, they used the term Onset of Plasma Lactate. They were trying to identify the place where lactate increases exponentially in plasma or essentially they were trying to find the point of maximum sustained effort.

And this is just the beginning of the confusion. Today, OBLA is a moderately searched term in google which means that some athletes still hear it. And 4.0 mmol/l of lactate is still a commonly used variable in the assessment of an athlete's conditioning. We will discuss this more below. And many researchers are using OBLA to mean the maximal lactate steady state which is what the original intent of the term was. And some are using it to mean where the blood first starts to rise over baseline or near 2 mmol/l.

What is IAT or the Individual Anaerobic Threshold?
Three German sports scientists in 1981 showed that the lactate levels at this maximum steady state varied substantially and frequently were below 4 mmol/l and sometimes higher. They developed a test to find this individual level and called it the Individual Anaerobic Threshold. (Stegmann H., Kindermann W., Schnabel A: Lactate kinetics and individual anaerobic threshold.) Notice that the anaerobic threshold which was originally associated with an initial rise of lactate above baseline at a lactate level that was probably near 2 mmol/l for most people was raised to 4.0 mmol/l by Mader and now is for most athletes somewhere in between these two points. Confusing, you bet. We are far from done with confusion, because enter a new term that perhaps makes more sense. It is the Maximal Lactate Steady State or MaxLass or MLSS

What is the maximal lactate steady state?
I do not know who first named this term. In 1966 a German sports scientist Joseph Keul used the term maximal steady state but in German. In 1975 an American, Londeree used the term maximal steady state in the title of an article using non-athletes on a treadmill. In 1981 another American, Lafontaine showed that for male runners the pace that produce 2.2 mmol/l of lactate on a treadmill correlated extremely high with the pace used to complete a 8 km run. Similar to what the OBLA people had shown but using 2.2 mmol/ instead of 4 mmol/l. Lafontaine called the lactate level the maximal steady state implying that it was the highest steady state for which lactate remained constant. In 1982 in an article by Stegmann and Kindermann, they used the term "maximal lactate steady state." That is the earliest that we have found the term used in any literature. If any reader knows of an earlier use of this term, let us know.

The maximal lactate steady state or MaxLass or MLSS is the term of choice to indicate the effort level where a real transition takes place. Above this pace, lactate will accumulate rapidly in the muscle and blood. Eventually the muscles affected will not be able to contract. When this happens the athlete will often adjust by using awkward movement, essentially using other muscles, to finish a race. It is not uncommon to see a swimmer's perfect stroke break down a few meters from the finish. The swimmer will continue on for the final few seconds by adjusting his or her stroke thereby using muscles to finish the race that are not shut down by acidosis. You also often see this in running races especially those from 800 m to 3000 m when the runner's normal stride falls apart. In the above chart on steady state runs the maximal lactate steady state is somewhat above 4.2 m/s and below 4.4 m/s. To find the exact spot is painstaking and, we believe, not worth it. It is of interest to researchers but it is not necessary to know it to train wisely.

Why isn't the Maximal Lactate Steady State worth measuring?
We have just said that the maximal lactate steady state is the only valid point where there is a real transition or threshold, but that it is not worth measuring. First, of all it is certainly worth the effort for researchers to measure it because it will be a variable in their work that should be accounted for. But for a coach or athlete, it is probably a waste of time. There are other measures much more easily done that correlate almost perfectly with MLSS. And there is no need to train at or near the MLSS because it is too intensive for most athletes to handle, especially elite athletes. So for a coach it is expedient to use these other easier methods. And what is another measure? We recommend that the most useful measure is the pace or effort at 4 mmol/l.

So the best measure for lactate testing is the one that most say is meaningless?
We have had many conversations with respected researchers in exercise physiology who have told us it is a complete waste of time to measure the 4 mmol/l level because it has been completely discredited years ago. We say we understand this but the more sophisticated point of view is to measure it and forget about attempts to measure the lactate threshold or MLSS. This sounds like heresy to these researchers some of whom have invested a lot of time in using various methods to estimate the MLSS. We counter that there is an even more sophisticated way of looking at lactate testing than they are using. This often does not make too many friends but we have found that many of the coaches understand what we are doing when it is explained to them and that the ideas of Mader and Olbrecht coincide more with the views they have for training their athletes.

Why is 4 mmol/l the best measure for lactate testing?
First, it is not the best measure but it sure is an easy one to find and use. Look at the curve we presented above. It is presented again here for convenience. Is it difficult to find the point where the lactate is 4 mmol/l?

lactate curve for recreational runner

The 4 mmol/l pace or effort level is easy to find. And 4 mmol/l correlates with performance for most endurance athletes. You do not want to train at the 4 mmol/l pace so if someone is planning training zones it is just as easy to do it with this measure. See the triathlon assessment section for some ideas. And over time the 4 mmol/l represents a measure to evaluate the progress of an athlete. Here is one from a world-class rower. There is an interesting story that goes with this rower concerning training and is on another part of our web site.

lactate curve for world class rower

What we are recommending is not 4.0 mmol/l specifically but a fixed level that is easy to measure. We were once at a sports medicine conference in Barbados and some Cuban sports scientists were there. They worked mostly with runners and used a 3 mmol/l level instead. It was closer to the threshold for most of their runners. The reason why we recommend 4 mmol/l is that is nearly always on the upswing of the curve and easy to identify. Too much higher and it is getting out of the range of what the threshold could be and too low and it might be too close to the gently rising part of the curve. It is a good compromise, based on lots of historical data, and it works.

What about all those ways people try to measure the lactate threshold?
On our CD-ROM we discuss several methods people have come up with to measure the lactate threshold. A year and a half ago a long extensive review of all the ways people have used to measure the threshold was published. It was by Oliver Faude, Wilfried Kindermann and Tim Meyer. In the near future, there will be a thorough discussion of thresholds by Sports Resource Group. Here is the Faude reference and another good one by Ronald Binder and several other authors.

Faude, O., W. Kindermann, et al. (2009). "Lactate threshold concepts: how valid are they?" Sports Medicine 39(6): 469-90.

Binder, R. K., M. Wonisch, et al. (2008). "Methodological approach to the first and second lactate threshold in incremental cardiopulmonary exercise testing." European Journal of Cardiovascular Prevention & Rehabilitation 15(6): 726-34.

In these two references the controversy over the various uses of the same terms across studies is discussed in detail. It is confusing. We prefer that lactate threshold, anaerobic threshold and maximal lactate steady state be regarded as defining the same phenomenon. We know that this will probably not happen universally in the near term, as many people believe differently. But you should know about the controversy so you are less confused. Here is a blog on rowing that illustrates the confusion. But also remember that there is no value to training at any particular lactate value. That sounds like heresy for people recommending and selling lactate analyzers. But not if you understand the logic of what we are saying.

Will there be more on this topic?
Of course but this is all for now for this section. Send in your questions and we will try to answer them.

Some Myths

Does lactate or lactic Acid cause muscle soreness?
No. First of all lactic acid is not in the muscles. It is lactate. And lactate does not cause any problems. When lactate is produced during the breakdown of glucose, hydrogen ions are also produced. This causes the muscles to get more acidic, and may cause fatigue. This was thought to be part of what causes the soreness or as some have described it the burn in the muscles. It is what the manufacturers of the first portable lactate analyzer thought when they developed it back in the early 1990's. Our 800 number is based on the concept of "burn" as the last 4 digits spell BURN on the telephone dial. However, it is now thought that the burning sensation in the muscles is cause by tiny muscle tears. This is just one of many myths surrounding lactate or lactic acid. From now on we will leave out lactic acid since the reader gets the idea that it is like a ghost, not really present.

So lactate does not cause fatigue?
That is the current understanding. Hydrogen ions and some other metabolites are thought to be the culprits. The importance of lactate in this is that it rises at the same rate as the hydrogen ions that cause fatigue. And lactate is easy to measure.  So measuring lactate allows you to know when fatigue will occur.

Fatigue is not the best word to use but many use it. During intense exercise the muscles refuse to contract properly or quickly so some has called this fatigue. But if the athlete just slows down a little bit he can often continue at a fairly fast pace. Just not as fast as he wants to.

What is fatigue?
Fatigue has many definitions. When a marathoner has to slow down about 2 hours into a race is that fatigue? When an competitor in an Ironman race has to stop during the run and walk in or ask for a ride to the finish, is that fatigue? When a football defenseman cannot keep up with the receiver he is covering, is that fatigue? Imagine a dozen or more ways that an athlete is not as fresh as when the race or game began. Fatigue has many forms including the one that causes you to sleep 12 hours after you have been working 20 hours a day for nearly a week.

Isn't lactate a waste product?
This myth is pretty much buried today but when we first went to Kona 14 years ago for the Ironman world championships, more than one coach thought lactate was nothing more than an unwanted by-product of energy metabolism. While most know now that is not true, few know just what part lactate plays in a race. The answer is that lactate is the main fuel for nearly all athletes during an athletic competition. It is not a waste product; it is what enables an athlete to win.

Isn't lactate only produced when I go fast, above the lactate threshold?
It wasn't just coaches and athletes who were confused. Many exercise physiologists didn't understand what was happening either and even today some don't. You see the comment that the lactate or anaerobic threshold is the point where the body starts to mainly use anaerobic metabolism. This is complete nonsense. Below the anaerobic threshold the body uses a mixture of aerobic and anaerobic energy. Above the lactate or anaerobic threshold the body uses a mixture of aerobic and anaerobic energy. The percentage of each may only be a small bit different just above from just below. Thus, the term anaerobic threshold is a poor term to describe what is going on. An exercise physiologist who saw the first curves that showed the effects of oxygen consumption as exercise increased pointed to a break in the curve and said that is where the body is going anaerobic. He was wrong but the idea has stuck for nearly 50 years (this is discussed in the answer to another question above.)

How does lactate testing help me get better?
When lactate testing first arose in the West (it was mainly something the East Germans and Soviets did), exercise physiologists thought some kind of magic was involved. An ex rower who was in the 1976 Olympics said that every one on the US team was spooked because the Soviets and the East Germans were getting their blood taken after the races. When they asked what it was for, they were told the East Germans were measuring lactate. They were also winning most of the medals. There is no magic. But lactate testing tells the knowledgeable coach a lot that no other testing can. So properly used it may look like magic but in reality it is mostly straightforward.

Doesn't lactate tell me the optimum intensity to exercise at?
Not by itself. But in the hands of some real experts, lactate testing can tell you how much both your aerobic and anaerobic systems are being utilized at each intensity. From that you can learn what kind of training effects a particular pace will produce. A few high-level coaches have sophisticated simulation programs that fine-tune this analysis for extremely elite athletes.

Lactate tests can be used to develop good training paces and we discuss this in the triathlon section.  But the main use of testing is to assess the athlete and his or her training. Over time a good coach will learn what works for each athlete. Not magic but good insight using the best tools to assess the conditioning of the athlete.

Isn't the anaerobic threshold or lactate threshold the optimum point at which to train?
It is amazing the number of people who still believe this. The truth is that the anaerobic threshold or lactate threshold is the one point not to train at. One of the coaches that uses our products calls it the “no-go zone.”  That statement will blow away of lot of high-priced coaches’ training philosophy. The rationale went something like this. The anaerobic threshold is the highest effort level that one can maintain for an extended period of time. Thus, it will produce the biggest training effect. So train at the anaerobic threshold and then when it increases, keep increasing the training intensity and the athlete will get better and better. Sounds logical, doesn't it? Unfortunately that is not how our bodies work.

Why doesn't training at the anaerobic or lactate threshold work?
Simply, because our bodies get better by breaking down from exercise, and then rebuilding.  They respond by making the muscle, joint, cells a little bit better at doing what caused it to break down. The problem with the anaerobic threshold as a workout pace, is that it causes a maximum break-down: the longest possible workout possible at the highest intensity. It will take the body a long time to recover from such a major break-down.  And by repeating this killer pace in daily training sessions, the body is broken down even more and there is no chance to regenerate back to where it once was, let alone reach a new level.

No, the best training philosophy is one that allows enough time for regeneration and finds workouts that actually speed regeneration up as opposed to prolonging the break-down phase. That is the science of winning and is the title of Jan Olbrecht's book on training.

Do sports scientists understand what causes the lactate or anaerobic threshold?
Nearly all do not and some will say it is a mystery. They will generally say the LT is not well understood. Well in 1986 Alois Mader published a paper that explained it quite well. He started from the point that some athletes did better than others at races even though their anaerobic thresholds were at exactly the same effort level. He had no idea why.  What was perplexing, was that two athletes each with the same anaerobic threshold level would beat each other but at different distances. For example, Athlete A would win the 100 m freestyle swimming race over Athlete B, while at 200 m Athlete B would comfortably beat Athlete A. That threw out the whole idea of the anaerobic threshold as a predictor of race success. So was it all nonsense? Some coaches and exercise physiologists said it was mumbo jumbo and lactate testing was a waste of time. So these enlightened scientists decided to ignore the anaerobic threshold because they did not find is useful.  But what did Mader find out that nearly everyone even today ignores? It is all over this site and covered in detail in the CD-ROM. Mader discovered that the anaerobic system was also important, and explained the differences in race performance.  Interestingly, lactate testing allows you to assess the anaerobic system as well.

Some References for Mader's work. They can be a little daunting but are described in detail on our CDROM and briefly in the anaerobic pages of our triathlon section.

Mader, A. and H. Heck (1986). "A theory of the metabolic origin of "anaerobic threshold"." International Journal of Sports Medicine 7(Sup): S45-S65.

Mader, A. (1991). "Evaluation of the endurance performance of marathon runners and theoretical analysis of test results." Journal of Sports Medicine and Physical Fitness 31(1): 1-19.

Mader, A. (2003). "Glycolysis and oxidative phosphorylation as a function of cytosolic phosphorylation state and power output of the muscle cell." European Journal of Applied Physiology 88(4-5): 317-38.

Hartmann, U., & Mader, A. (1996). The metabolic basis of rowing. In Rogozkin & R. J. Maughan (Eds.), Current research in sports science (pp. 179-185). New York: Plenum Press.

Mader, A., Hartmann, U., Hollmann, W. (1988). Der Einfluß der Ausdauer auf die 6minütige maximale anaerobe und aerobe Arbeitskapazität eines Eliteruderers. S. 62-79. In: Steinacker, J.: Rudern: Sportmedizinische und sportwissenschaftliche Aspekte. Berlin: Springer.

Mader, A., (1994). Aussagekraft der laktatieistungskurve in kombination mit anaeroben tests zur bestimmung der stoffwechselkapazität. In: Clasing, D., Weicker, H., Boening, D.: Stellenwert der Laktatbestimmung in der Leistungsdiagnostik. Stuttgart: G. Fischer.

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