Why I No Longer Like Lactate Testing: Prime Appraisal or Wasted Effort?

By April 30, 2015 December 9th, 2016 Exercise

As both physician and coach, working with an athlete is an ongoing process of intense assessment followed by specific actions. Included are various physical, biochemical, mental, and emotional evaluations that yield essential information vital for follow-up activity.

Follow up actions include treatment of abnormal physical findings, such as muscle imbalance, recommending optimal eating, and creating a training program based on individual needs. Other issues involve regulating stress, mental imagery, and simple biofeedback. Responses to these actions are also assessed, and become part of an ongoing process.

The back-and-forth assessment-action process persists with the continual goal of building fitness and improving performance without sacrificing health. Pushing one’s body while maintaining this delicate balance may be the best way to reach optimal athletic potential.

Testing 1, 2, 3 . . .

When I started working with athletes in 1977, measuring an individual’s many health and fitness features was a priority. My education emphasized this process, and the experience quickly taught me how important it would be in uncovering the cause of an injury and other problems that interfered with athletic progress. In a real sense, a large database of personal information was vital for success.

Evaluations included treadmill and cycling testing in my clinic, and field evaluations on the track, in the pool, and at other locations. From samples of blood, urine, and saliva, more assessments meant additional data to better fine-tune the athlete. Specific tests included lactate, along with hormones, fats, vitamins, minerals, enzymes, red and white blood cells, and many others. In addition, analysis of posture and gait, and biofeedback assessments including muscle testing were important. By measuring oxygen uptake and carbon dioxide output, the percentage of sugar- and fat-burning at specific heart rates could be determined. An ongoing oral health history may have been the most important assessment tool, which is still true today.

This process took considerable time. As the years passed I reduced the use of those tests that gave back less information—especially the ones that told me what other more useful evaluations provided. Low on the list was blood lactate.

Unloading Lactate

Today’s technology allows for easy and accurate measurement of lactate. Traditionally tested from blood, other high tech tests will hit the market soon. For example, a new biosensor in the form of a temporary tattoo is being developed which will measure lactate in sweat.

Lactate is an important part of a healthy metabolism, during both aerobic and anaerobic activity. Far from being a “waste product” or the limiting factor in performance as once thought, this metabolite of muscle lactic acid is always being produced, and serves as an important source of energy for the whole body. But obtaining a lactate level may not be as meaningful as most think.

Training lactate levels do not reflect production from lactic acid in muscles, but rather, its clearance from the blood. This might appear academic, but those who metabolize it quicker have lower levels, while others may maintain higher ones. The ability to break down lactate is a reflection of overall health, in particular that of the liver and kidneys, with the nutritional status being especially important. All these factors can change from day to day, and even within a single day.

Thiamin (vitamin B1) and magnesium are examples of two key substances necessary in sufficient amounts to properly metabolize lactate. Lower levels of these nutrients are associated with higher lactate readings, with the real possibility of misinterpretation and other errors when applying the results to training.

A computerized diet analysis, which I used throughout my career, is still an excellent, easy, and inexpensive way to assess one’s nutrient intake. In large numbers of athletes, thiamin and magnesium (and often other nutrients) does not even reach minimum RDA levels, a reflection of poor eating. In addition to lactate, this will have negative effects on other areas of athletic function as well. (The answer to this problem is not supplementation but improving the overall quality of food consumption.)

Blood lactate is often measured to obtain information about lactate and or anaerobic thresholds (AT) associated with increased exertion, higher heart rate, and changes in energy needs. Inclusion of much more anaerobic, sugar-burning activity becomes necessary at this training level. But there is no single lactate level clearly associated with these thresholds. And, as discussed below, aerobic development, not anaerobic, is a key to endurance success.

Whenever I hear that “T” term it reminds me of the Moody Blues 1969 hit album, “On the Threshold of a Dream”—that’s creative. The lactate and anaerobic thresholds, on the other hand, are almost academic.


While endurance success follows aerobic development, there is still a place for anaerobic training. When doing so, I prefer using the full spectrum of the neuromuscular system—the brain’s stimulation of all the muscle fibers—rather than smaller groups of them associated with a particular heart rate zone. This involves increasing the pace from rest through max aerobic levels to high anaerobic states and back down. This is a “no-zone” approach, and when properly implemented, which includes a significant warm up and cool down, the full-body benefits are boundless.

Endurance racing relies primarily on aerobic metabolism. In fact, 98 to 99 percent or more of an athlete’s energy is generated by the aerobic system during a triathlon or marathon, for example. This being the case, why the popularity of such a focus on finding thresholds of anaerobic lactate levels? It is high risk with low potential return as anaerobic workouts are more commonly associated with injury, reduced health, and overtraining.

Decades ago I learned to focus primarily on developing the aerobic system of endurance athletes. When followed strictly, the results were better performance, increased physical stability to eliminate and prevent injuries, and improved overall health. And, it allowed individuals to utilize more body fat during a race, reducing reliance of foods and formulas. Many professional and amateur athletes, and trainers and coaches, use this system today.

As with AT, higher lactate levels reflect an anaerobic state. While this is very important to know during training, relying on lactate to know it is impractical. The test is not always reproducible, not always available with enough regularity for some athletes, and is associated with some cost. Keep it simple: just knowing the heart rate during different levels of activity can provide the same information.

Instead of a variety of different training zones, I prefer the simple distinction between two: aerobic and anaerobic. Just knowing you are above the max aerobic heart rate indicates anaerobic efforts. So, the lactate or anaerobic threshold is distinctly different from the maximum aerobic heart rate. And, one cannot obtain the max aerobic heart rate by measuring blood lactate or AT.

RQ and Max Aerobic HR

With proper protocol and interpretation, the respiratory quotient (RQ) is an effective treadmill test that provides athletes with the percent fat and sugar burning at various heart rates. This also helps determine the maximum aerobic heart rate, which is associated with the body’s ability to use high levels of fat for energy. As true aerobic training progresses, one will ultimately run or bike faster, for example, at the same heart rate because fat provides more fuel. Even without implementing anaerobic training, this will lead to faster race performances.

Unfortunately, RQ is still not commonly employed by coaches and athletes, despite the relative ease of today’s treadmill testing. However, the assessment is not widely available, and can be costly, especially considering follow up evaluations.

Based on many tests, including RQ, I developed the 180 Formula in the early 1980s. This allows athletes to find their maximum aerobic heart rate for use during training. In addition, the same heart rate is used to perform an important evaluation, the MAF Test, which helps monitor training progress (e.g., aerobic development and increased fat-burning).

I should add that, among the tests that remain popular, VO2max is also of little true value. For most athletes, the only benefit of performing this evaluation is that the process can sometimes also provide RQ data.

I no longer like lactate testing because there are more reliable, easier, and cheaper evaluations that all athletes can regularly utilize for effective training. Included are the 180 Formula, heart rate monitoring, and performing the MAF test. These can contribute significantly to the ultimate goal of both better performance and improved health.


  • Phil says:

    Hi Ivan,

    Had a Metabolic Efficiency Test, and here’s the RER data I got for you. I’m 24 years old and have been using 180-24-5 = 151 bpm for MAF. Took away the additional 5 to be conservative.

    0.76 at 134 bpm
    0.76 at 141 bpm
    0.78 at 149 bpm
    0.79 at 156 bpm
    0.83 at 162 bpm
    0.84 at 169 bpm
    0.88 at 176 bpm
    0.90 at 183 bpm

    So just to reiterate, is my MAF heart rate particularly at the RER of 0.70 – 0.73, or 0.85 – 0.87? Just wanna confirm since I see two different answers in the previous comments, and ultimately if I no longer have to subtract the extra 5 bpm for my MAF heart rate.


    • Phil:

      What did you take 5 BPM off for?

      It’s likely that your MAF is at around an RER of .78-.79. Do you have access to tests measuring the rate (not percentage) of fat-burning?

      • Phil says:

        I took off 5 just to stay conservative. I took the winter off completely for running, so when I started again, since I was just getting back into training, I took off an additional 5.

        I have rate data for you, and I think that answered my question. Here’s what I got:

        At 141bpm, 154 kcal/hr of carbs, 614 kcal/hr of fat (RER of 0.76)

        At 149 bpm, 228 kcal/hr of carbs, 617 kcal/hr of fat (RER of 0.78)

        At 156 bpm, 244 kcal/hr of carbs, 628 kcal/hr of fat. (RER of 0.79)

        And then…. At 162 bpm, 411 kcal/hr of carbs and 545 kcal/hr of fat. (RER of 0.83)

        So with that said, the 180 formula is an exact match to an MET test and my MAF is 156 bpm? Guess I didn’t need to take away the additional 5 bpm. It’s incredible seeing the accuracy of the 180 formula through an MET test.

      • Phil says:

        Hi Ivan,

        Took an additional 5 off because I took all of last winter off. When I got back into MAF training after a few months, wasn’t sure if the additional 5 was necessary, so I did it to be conservative.

        Here’s the rate data:

        At 141 bpm 614 kcal/hr of fat, 154 kcal/hr of carbs (0.76)

        At 149 bpm 617 kcal/hr of fat, 228 kcal/hr of carbs (0.78)

        At 156 bpm 628 kcal/hr of fat, 244 kcal/hr of carbs (0.79)

        At 162 bpm 545 kcal/hr of fat, 411 kcal/hr of carbs (0.83)

        This probably answers my question. Awesome to see how accurate the 180 formula is first-hand through an extensive analysis. Let me know if you have any thoughts on the data!


  • Alex says:

    Ok I just called then and got confirmation that my aerobic threshold (AnT) is indeed 163-178 BPM. However ventilatory thresholds were not tested.

    • Alex:

      The AnT is the anaerobic threshold, which is a point, not a range. I’m looking for the AerT (or AeT). But without knowing more except what you’re telling me, I suspect your numbers mean that the AerT is 163 and 178, for example. If this is the case, I’d suspect that your VT1 is 165 or some such. However, I wouldn’t move on using these numbers until I’ve confirmed where the AerT (as opposed to the AnT) is located.

  • Alex says:

    thats my aerobic threshold. and i will give you the exact details when i get a copy of my analysis

  • Alex says:

    Ivan, question to you and Phil. I’ve been running at my calculated MAF heart rate for two months (153) and decided to ‘treat’ myself to a blood lactate test. I am unbelievably confused now. The 153 always felt slow but the test has given me a max aerobic threshold of 173!? 20!!! Beats higher. What are your thoughts on this? Should I start training at 173?

  • Brent says:

    Hi, you mention that RQ can be used to help determine max aerobic heart rate. I have recently done a metabolic assessment which gave me RQ data for different HR. What RQ value would correspond to the MAF HR? I have read on another forum (RunningAHEAD) that a the HR at RQ of 0.78 can be used for the MAF HR – is this correct?

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