Lactate Threshold - Basic Information
The Lactate Threshold Test - Its Importance for Training
Dr. Edward Coyle has identified three factors that are 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 though we believe that V02 max varies quite dramatically over time and what Dr. Coyle refers to is the maximum value for V02 max that an athlete can reach. At any moment the V02 max of an athlete as measured on a V02 test can change from one period of training to another due to training, racing, illness or inactivity. That is a somewhat different issue than training what affects the value of the Lactate Threshold is at any given moment but they are not unrelated. Generally as an athlete's V02 max goes up or down the lactate threshold will do the same. But not always and that is what is important to know. Just when are these two important indicators of performance not tied together and why?
Understanding this relationship is the key to proper physiological training not only for an endurance athlete but for any athlete whether he be a hockey player, swimmer, speed skater, soccer player, track cyclist or kayaker etc. But for endurance athletes such as road cyclists, marathoners, triathletes, cross country skiers, rowers and distance swimmers, optimizing their V02 max and lactate threshold is of prime importance and these athletes must emphasize this in their training.
The following will be a discussion of the Lactate Threshold and for those interested there is a more detailed discussion of thresholds in general and how to train them on our thresholds page and in our triathlon section.
To understand the reason lactate is different from every other variable a coach and athlete can measure and thus the reason why the lactate threshold is so important is based on lactate's unique role in energy generation. But first two key relationships.
First - there exist an effort level called the maximal lactate steady state (MaxLass) that an athlete can continue at for an extended period of time without having to slow down, usually an hour but sometimes longer. As long as the athlete maintains this effort level his or her lactate level will remain constant. At small effort levels above this point the athlete's lactate level will rise slowly and he or she will be forced to stop, sometimes within a few minutes or sometimes after an extended period of 20-30 minutes. Above this maximal lactate steady state there are no more steady states but an inevitable and frequently rapid progression to exhaustion. This effort level is also often called the lactate threshold, the anaerobic threshold or the onset of blood lactate accumulation or OBLA. The chart below shows that above 4.2 m/s the lactate is no longer in a steady state and the athletes is forced to stop.
Second - the maximal lactate steady state or the lactate threshold is the single best indicator of endurance performance known. Generally the athlete with the maximal lactate steady state at the higher effort level (speed or power) will be faster in an endurance event. Increases in the maximal lactate steady state are almost always accompanied by improvements in race performance for endurance events. So frequent lactate threshold testing (every 4-6 weeks) is usually the best indicator of potential race performance for endurance events. It is also generally the best measure for improvements due to training or a lack of response to training. For short events such as swimming and rowing the maximal lactate steady state is also highly correlated with performance but anaerobic capacity or the ability to produce lactate and speed will become more important as the event get shorter.
This topic is covered in detail on our Secrets of Lactate CD-ROM
While each of the terms (MaxLass, lactate threshold, anaerobic threshold, obla) are associated with this maximum steady state condition, they have other definitions and uses and we discuss these on the thresholds page. There is even a term called the aerobic threshold which has appeared in the training literature and the various number of terms has caused much confusion with both coaches and athletes.
Lactate Threshold Training
Training to improve the maximal lactate steady state is often called lactate threshold training. However, training intensities at the actual lactate threshold or maximal lactate steady state are not recommend to improve these levels. It is important to understand this distinction. Why? Because training at these specific effort levels is usually not good for the endurance athlete. They are often a formula for over training. These intensities are too stressful for most athletes, especially elite athletes. This may sound contradictory but the better the athlete the more dangerous is training near or above the threshold. If you do not understand that now, you should by the time you finish the rest of the sections on this site.
Training intensities can be based on the lactate threshold (for example often regenerative workouts for elite athletes are at a low percentage of the LT, such as 70% of the LT pace.) They also can be much higher. Training at the higher intensities is probably the most valuable training but should be very, very limited since an athlete can quickly over train when exercising at the lactate threshold or higher. Very often endurance athletes do not feel much stress when training at the lactate threshold or higher but this can be deceiving as the stress they are putting on the aerobic system at these high intensities can break down their aerobic system too much and result in less aerobic capacity, not more.
So frequent training at the lactate threshold will most likely lower the lactate threshold and training at lower levels and significantly above it will often raise it.
The lactate threshold is best used to evaluate the results of a training program. It is the best marker to evaluate whether all those hours of training are paying off.
Again a very detailed discussion of thresholds, obla and the maximal lactate steady state is on our Thresholds page. There you will find definitions of the different types of thresholds, how they are used for training and how you can train them for a better performance.
Why Lactate is Unique
Lactate is the unique metabolic variable that indicates the capability of the muscles for an athletic performance. We emphasize "unique" in the preceding sentence because no other metabolic parameter provides the same information. Lactate is an output of the anaerobic process and a fuel for the aerobic process and levels of it in the blood during exercise is indicative of the strength of each system. No other parameter provides this same information.
The ability of the muscles to reach a peak performance during an athletic event requires that the energy systems providing energy be "fine tuned" or "balanced" properly so that the athlete can generate the highest amount of energy per unit of time during a race. Proper training is what accomplishes this fine tuning or optimal balance of the aerobic and anaerobic systems and it is lactate testing that lets the coach know if the balance has been obtained or how each energy system must be trained in order to obtain the balance. To illustrate what is meant by balancing look at the following table:
Why affects the running speed at a specific distance. Before you say VO2 max, consider that world class 400 m runners have VO2 max's almost as high as marathoners. And top middle distance runners definitely have VO2 max's as high as marathoners. What is the difference? Their energy systems are balanced completely differently, such that they will excel at a specific distance. Knowing what this balance is for each athlete is the secret to success in both sprints and distance events. This balance produces very different lactate curves. Knowing your curve will tell you what you can expect to do in a race, especially the one you have been preparing for with all that training.
The Steering Principle gets you to your goal, an optimum performance?
Coaching is a profession requiring both art and science. The building blocks for an optimal performance are many and must be constructed in a proper sequence and must recognize that each individual is different. Some of these building blocks are
- correct technique
- positive mental attitude and
- a proper diet.
However, the cornerstone for this building is precise physiological training. That is the main reason an athlete spends so much time in the water, on the bike, on the track or the road, in the weight room or wherever training is best conducted. Ask yourself, do you know if all those miles/hours of training are paying out?
But what is appropriate physiological training?
- It is not volume or else those who put in the most hours/miles would be the winners.
- It is not intensity or else those who pushed themselves the hardest would be the winners.
- It is not someone's favorite workout or else everyone would be copying the magic workout or training pace.
It turns out that each individual has their own way of adapting and any smart training plan must recognize this by constantly adjusting the athlete's training based on his or her response to previous training. Has the training been effective? How do you know? That's what lactate testing tells you.
As we pointed out above the proper balance differs by event and by individual. This is a fact of life. Each has to find his or her own way to the proper balance of the energy systems and peak conditioning on the day that counts, race day. Each must measure their progress, adjust the training program and then do the training. It is a constant evaluation of the athlete's conditioning followed by a readjustment of the training program. The athlete is gradually and systematically steered to an optimal performance.
With proper protocols a portable lactate analyzer such as one of the two pictured on the left enables the coach to measure both the aerobic and anaerobic conditioning of each athlete. Information about both is necessary for the coach to optimize the conditioning of each athlete whether they are a 50 meter freestyle swimmer (about 22 seconds plus per race) or an Ironman triathlete (over 8 hours per race for the world's best). With information on each energy system the coach can plan, control and monitor the training of athletes with a precision not available before. Lactate testing provides the important information that enables the coach to individualize the intensity of each athlete's workout and control their training so they reach performance objectives. No over-training and no surprises come race day. For information on two accurate and fast portable lactate analyzers see the Lactate Scout and Lactate Plus sections on our web site.
How Does Lactate Testing do This?
Provides a multi-dimensional profile of conditioning. Because lactate is produced by the anaerobic system and used by the aerobic system it is the only marker available for measuring each system. The amount of energy an athlete can produce per unit of time depends on the development of both systems which is why they have to be balanced. (Essentially this means training the anaerobic system to a level that is appropriate for the athlete's aerobic capacity.) This balance will depend upon the event for which the athlete is competing and will also depend upon which part of the training cycle the athlete is in. The closer the athlete gets to the "big" event the balance will have to be "fine tuned" for a peak performance. See the thresholds page for more detailed information.
Show adaptation in each system. Over time changes in blood lactate levels tell the coach what physiological adaptation has taken place in each system. It tells the coach which forms of training are working or not working. Training time becomes much more efficient as the athlete performs only workouts that work. Your analyzer becomes a "training compass" that "steers" each athlete in the right direction. It is much more relevant than heart rate monitoring which reflects a general overall body response to stress and doesn't necessarily reflect what is happening in the muscles or with the anaerobic system. It is much more versatile than V02 testing which requires very expensive equipment and requires experts to administrate the test properly.
Teaches coaches and athletes what is required for a peak performance. Lactate testing is also a learning and motivating experience for coaches and athletes as they become much more aware of the interactions of variables and the other nuances that affect workouts as well as performance. Since the emphasis will be on training energy systems and not the use of very broad training zones, coaches will understand what works best for each energy system and why, what may be counter-productive and when and in what sequence various types of training are appropriate.
The Best Information in the World on Lactate Testing
Lactate Threshold Testing Information for the coach. The Secrets of Lactate CD-ROM was written for the coach and is anything but trivial. There are 16 tutorials on different aspects of lactate testing, metabolism, interpretation with in-depth discussions in three sports (swimming, rowing and triathlon). In addition there are 8 extensive discussions on various topics such as the lactate threshold and anaerobic threshold, heart rates and lactate, proper lactate test protocols and how to make your lactate testing consistent from test to test. There is a new interactive module on exercise metabolism which animates how the body's energy systems respond to various races and training exercises. The CD-ROM is the most complete discussion of lactate testing in the world. If you click on the link above or the image below you will see a more detailed discussion that also provides links to sample slides in the tutorials.
Training information for the coach. Probably the two best books in the world for explaining the science of training are Jan Olbrecht's The Science of Winning (published October 2000) and Ernie Maglischo's Swimming Fastest (published January 2003). These are two scientists who have spent their lives with athletes as opposed to academia. Both have Ph.D.'s in exercise science but don't live in academic ivory towers. Jan has worked with top athletes in Europe such as world record holders, triathlete - Luc van Lierde and swimmer - Pieter van den Hoogenband while Ernie has coached several NCAA champion teams and swimmers. Jan helped train 28 medial winners at the Athens Olympics. These two books are wonderfully clear and offer different perspectives from most on what it takes to maximize performance.
Another great book is the Physiological Tests for Elite Athletes written by the Australian Sports Commission. Here is a description of how the most successful sports program in the world is testing their athletes in 17 internationally recognized sports.