Metabolic Testing


Receiving Pre-Test Instructions With SportsLab




  Metabolic testing is the most accurate and reliable way to establish your daily training intensities and ensure the best possible results for your effort.

  SportsLab utilizes specific metabolic testing methods and unique personalized protocols that will identify things such as:  optimal fat burning intensity, aerobic threshold, adaptations to training, optimal interval training effort, optimal recovery time, analyzing equipment performance and/or optimizing bike fit…etc.


 What can Metabolic Testing provide answers to ?

- “How hard should I be pushing myself each day”?

- “How long should I train/exercise each day”?

- “How often should I have days off”?

– “How can I know if I’m under or overtraining”?

these questions (and others) can be answered using metabolic testing.

Unfortunately, most people assume metabolic testing is only useful for elite athletes or research work and not needed at their current fitness level.

– The truth is, regardless of your fitness level, metabolic testing is one of the best values available to you.  It saves you time, eliminates uncertainty, optimizes your effort, and accelerates results while at the same time eliminating most causes of fitness and conditioning failures.

– Regardless of your current fitness, recognize the value of the above statements. Metabolic testing will help.

The various metabolic tests that may help you can be discussed anytime.   I welcome your inquiries and questions and invite you to call me to learn about metabolic testing.

Steve, (719) 360-5050



FyI reference —

Common Test Abbreviations

Blood Lactate Tests -

LBP /LBPHR  (lactate balance point / LBP Heart rate)

MLSS  (maximum lactate steady state)

ILC  (isolated lactate concentration)

LT – lactate “threshold” curve  (outdated, specific request only)


Common Respiratory Gas Analysis Terms-

Vo2 max (maximal oxygen uptake)

AT  (anaerobic threshold)

VT  (ventilatory threshold)

RER  (respiratory exchange ratio)

RMR  (resting metabolic rate)

Ve  (minute ventilation)

O2 Pulse  (oxygen pulse)

O2 Kinetics  (monitor)

CO2 Kinetics  (monitor)

 ECG (electrocardiograph)


More About Common Terms -

VO2 Max 

Maximal oxygen uptake during exercise, this defines the upper limits of the cardiopulmonary system. A few of the factors governing this are heart rate, stroke volume, and muscular ability to utilize oxygen. Some will argue this is the most important, and therefore the only variable worth measuring.

I agreed that VO2 max can be important to test for, However this is absolutely not the best way to determine your training intensities.

Maximal O2 uptake can however be useful  for monitoring plateaus during training and help keep track of overtraining by identifying disproportionate fluctuations in VO2 max.

For many decades now, achieving an individual VO2 max has been thought to be an essential part of a “well-structured” training plan.  Surprisingly, for essentially the same length of time, it has also been known that VO2 max is not the best way to determine your training intensities.

I also agree that maintaining high VO2 values during the season is really what it’s all about for VO2 measurement.

*Consider this:   (countless very well structured studies have proven at every level, from weekend enthusiast to fitness buff, to professional and world elite athletes) Athletes with equal VO2 Max often have very different athletic abilities (or, athletes with equal ability often have very different VO2 max).  Yet, these athletes with equal VO2 max train very differently day-to-day to achieve the same ability.

ATge / VT 

Anaerobic threshold via gas exchange (ATge) and Ventilatory Threshold (VT).

These terms are shrouded with misunderstanding and confusion. What follows is very brief and condensed.

I’ll open up the “can of worms” right now with the facts that has been known for years…… there is actually no Anaerobic Threshold, and there is actually MORE  available O2 as our metabolism shifts and relies more on Anaerobic metabolism.

The terms Anaerobic Threshold and Ventilatory Threshold are often used for the same (or similar) metabolic occurrences.  It was thought that A.T. designates a/the cause which occurs within the muscle (muscular anaerobiosis), and V.T. designates the ventilatory, or breathing pattern response to lactate buffering in the blood via off gassing CO2 through breathing.

The cause being the muscles production of lactic acid beyond the aerobic systems ability to maintain Ph balance.

Part of the response IS increased lactic acid production and blood lactate levels rising. This acidic pH condition in the blood is metabolized with bicarbonate buffering of the positively charged hydrogen ions (H+) of lactate. This buffering process produces an additional source of CO2 in the blood. Our body’s way of handling this CO2 is through expiration (breathing out). The more CO2 there is the more we need to off-gas it, causing a rise in respiration frequency. This produces what sometimes can observed at VT.

The problem with AT/VT as a means to determine training intensity lies in how our bodies actually “transition” from low to high intensities of effort.  Keep in mind there is rarely a recognizable “shift”, and there is actually not a “threshold” when looking at anaerobic metabolism.  In reality, using the antiquated standard “Lactate Inflection Curve”, any noticable  “shift” in aerobic/anaerobic metabolism is difficult if not nearly impossible to plot.  Reproducing these results with any consistency during testing has not be done.  Further, some athletes can control their breathing ways that makes the AT/VT pointless and completely inaccurate.

At best, AT/VT during CPX testing is referenced as a marker only and used in conjunction with parameters such as LBP, Ve, RER and O2/CO2 kinetics to help verify other data of the testing.


Respiratory Exchange Ratio –  This measures CO2 production divided by O2 consumption. We know that approximately 75% (+/- 5%) of O2 consumed is converted to CO2. At rest this value falls between .75 and .85. The type of fuel being utilized by the cell (carbs vs. fats) will alter this value.

Values of 1.0 or greater indicate carbohydrate metabolism, or anaerobic efforts.

Values below .85 indicate a greater reliance on fats for fuel. Since much greater O2 saturation (nearly 100%) is required to burn lipids, this measure can be useful for additional verification in determining aerobic levels.

RER is one of the key measures for those interested in weight loss. Be it for performance, personal, or clinical reasons. 


Resting Metabolic Rate.

This measures your daily basal caloric requirements.

I know this will likely trigger a lot of counter comments by the masses of pseudo-experts out there, however….. RMR/BMR are nearly useless measurements in healthy individuals and are certainly not a preferred way of determining caloric needs.

Ask me to explain this when you call, it is too complex to get into here.

RMR is attained via a 20 minute sampling taken during your most relaxed state. This sample can be done more than once if the state of relaxation seems elevated. By multiplying this 20 minute sample into a 24 hour time frame you have an estimation of daily caloric requirements.  Considering the cost associated with a RMR test, and this is still an estimation that is significantly influenced by numerous factors of varying intensity, this data can be obtained from formulas with essentially the same degree of accuracy needed for weight loss and other fitness training at no cost or discomfort.


Minute Ventilation.

This measures the volume of air moving into and out of the lungs. More specifically, it is the product of respiratory rate and exhaled volume of air with each breath. Ve has a direct correlation to VO2Max, as VO2 increases so does Ve in a linear sense.

Analysis of Ve on a comparative timeline graph helps in validation of other tests.

Monitoring and analysis of Ve while Field testing at altitude (above 10,000 ft.) here in Colorado has also produced some interesting data that has proven useful for research purposes at least.

O2 Pulse

Oxygen Pulse is an index number that represents O2 uptake divided by heart rate. For these uses O2 Pulse is monitored during testing and may be looked at during analysis as another variable for verification of other test data.

O2/CO2 Kinetics

O2/CO2 kinetics is simply the metabolic/respiratory dynamics of these gases. O2 kinetics is most active within the aerobic systems capabilities. Much to the surprise of many athletes, O2 utilization actually becomes more difficult for our bodies as we increase demand beyond current capacities even though the available O2 actually increases. Although logging of O2/CO2 kinetics data is available upon request, this is mostly used in real time breath-by-breath analysis. During high altitude testing this can be of value.


Electrocardiography is available as an add-on to any CPX test. By monitoring cardiac function during testing we are better able to realize the stress placed upon the cardiopulmonary system. This helps during test analysis as well. Extraneous factors such as the environment (altitude, cold, heat, humidity…), and more central factors (C.N.S., circulatory, cardiac…) have a significant impact on metabolic response and are often overlooked. ECG helps us determine whether responses are due to central/metabolic factors or environmental factors, and also to better estimate how much impact each is having. ECG is also a must for anyone post-acute cardiac rehab.



Lactate Balance Point/LBP heart rate is used to show the power and efficiency of the aerobic system. This test identifies the aerobic systems power by its ability to provide oxygen in the buffering and conversion of lactic acid after hard efforts. As lactate is cleared a “balance point” heart rate is determined which correlates to equilibrium in lactate clearance vs. production. When lactate production and clearance are equal, this is the true anaerobic/aerobic threshold. This is perhaps the most important test we use for determining training intensities.



Maximum lactate Steady State is simply the maximum effort level one is capable of sustaining without a steadily increasing lactate accumulation. This measure is useful in determining time trial and/or long race intensities. It is extremely important to know this before races to avoid “blowing up” “burning out” or “bonking”. This can also be used as a tracking measure during the season.


LT (classic lactate “curve”)

This is the standard lactate threshold test that has been in use for decades. We offer this test per request only. The problem with this test is it has always had poor tracking ability as well as repeatability. When analyzing the data for this test it is supposed to look like a checkmark when plotted. One of the problems with this test is that the test values build vague and inconsistent “checkmarks” (some are too round and others are flat with little shape). This leaves too much room for error and interpretation as well as inconstant follow up capacity.