Home Blog A New Paradigm for Performance Testing – Part 2

A New Paradigm for Performance Testing – Part 2

Written on April 22, 2010 at 7:00 am, by Eric Cressey

Yesterday, I featured Part 1 of this interview with Rick Cohen, MD, the president and founder of Bioletics.  Today, we pick up where we left off.

EC: Please tell us about the tests you use to determine mineral levels.  For what specific minerals are you testing, and what are some of the common findings you’re seeing that can make a big difference in how someone feels and performs?

RC: Our daily diet must contain adequate amount of macro minerals, which are necessary for all biochemical processes in the human body.  These minerals include calcium, chloride, magnesium, phosphorus, potassium, sulfur and sodium.  Among these, the most important are calcium and magnesium. Calcium helps to neutralize acidity, clear toxins and build bones; it also increases alkalinity and muscular flexibility. And while calcium receives a lot of media attention, the true king of all minerals is magnesium.

Magnesium is not only the single most important mineral in sports nutrition, but it is also one of the most critical elements in our body.  About 350 enzymatic functions depend on magnesium, including ATP, the key factor that creates energy for every cell.  Optimal magnesium levels enhance athletic endurance and strength by increasing metabolic efficiency.  Magnesium promotes muscular contractility, decreases oxygen consumption, and improves cardiovascular efficiency.

Unfortunately, magnesium deficiency is very common.  Inadequate dietary intake, sweat loss, physical and psychological stress and acidic beverages-such as energy drinks and sodas-cause the body to extract both magnesium and calcium from the bones and tissues in an effort to maintain proper blood pH.  This combination of mineral loss and acidity in the body will decrease athletic performance and prolong recovery.  It will also increase bone turnover and the resulting risk of stress fractures.  This is exactly what we were seeing in younger female athletes with accelerated bone loss.


Despite magnesium’s pivotal role in energy production and muscular health, many athletes are completely unaware of its critical importance.  Part of the problem is that there is not an easy or inexpensive test available for intracellular magnesium levels. While it may seem easy enough to assess levels of minerals – especially of magnesium and calcium in the blood – it’s not.

We have overcome this problem by using a functional marker of mineral balance called NTx.  Bones are living tissues that are constantly breaking down and rebuilding.  When they break down faster than they can rebuild, the body excretes increased amounts of NTx.  While NTx is not specific indicator of low magnesium, it tells us when an athlete has an intracellular calcium/magnesium imbalance as well as poor amino acid and/or vitamin D status.

EC: What’s your take on the most effective way to combat a magnesium deficiency that’s discovered?

RC: That’s where the other issue with magnesium comes into play: oral supplements work slowly; it can take more than a year to adequately restore your levels.  In the past, intravenous infusions were considered the most effective way to go.  But this was expensive and impractical for most athletes.  Based on our research at Bioletics, we have found that the use of a topical magnesium oil spray to be very effective at restoring low magnesium levels after only two to three months of use.

EC: What about the hormonal panel you guys run?  What does it include?

RC: As athletes, we want our body to have a positive anabolic to catabolic ratio.  In simple terms, anabolism is the process of growth and repair.  Your anabolic state is at its highest in your teens. Testosterone is the key anabolic hormone.  Catabolism is the process of breakdown and destruction. Your catabolic state is as its highest after injury and illness, and increases as we age.  Cortisol is the key catabolic hormone.  By measuring your saliva, it is possible to create a snapshot of both an athlete’s testosterone and cortisol balance as well as their anabolic/catabolic status.  Unfortunately, we frequently find low T/C ratios in athletes.


Testosterone is an important health and performance hormone-for both men and women.  It plays a key role in directing muscle growth and repair; it is what enables the body to generate optimal power and recover fully after such a hard effort.  Testosterone contributes to an athlete’s ability to stay focused, motivated and positive.  A premature decline in testosterone levels can be attributed to a number of different factors: poor diet, lack of sleep, excess body fat, nutritional deficiencies, environmental estrogens, and/or the use of medications, alcohol, and drugs.

Cortisol is a major steroid hormone produced in the adrenal glands.  It allows the body to cope during times of stress. Without proper cortisol response, you will not be able to effectively meet the daily challenges of life.  Cortisol levels exhibit a natural rise in the morning and fall at night.  If this rhythm is disrupted, the body’s mineral balance, immune response, blood sugar and stress responses will all be negatively affected.


While it is very difficult to reverse the natural age-related decline in testosterone, the effects of stress and training on testosterone can be minimized. Since even “positive” stress can deplete testosterone, those who participate in endurance-related sports are especially at risk for having lower than optimal levels.

Research shows that testosterone levels are temporarily decreased as a result of overtraining, while serum cortisol levels increase.  These changes in testosterone to cortisol balance are sometimes disastrous for an athlete, as they lead to elevated resting heart rate, poor performance, slow recovery, sore muscles, poor appetite, lethargy, muscle loss, irritability and a low sex drive.

Periodic assessments of both testosterone and cortisol are important when it comes to uncovering a potential hormonal deficiency or to simply fine tuning your training program.

EC: I’m curious about the essential amino acid test.  In particular, I’m wondering if you’re seeing issues in this regard not only in people who don’t consume enough protein, but also in folks who DO eat a lot of protein and for whatever reason don’t utilize it properly.

RC:  Of all the Bioletics assessments, the widespread deficiency in essential amino acids was the one that surprised me the most.  Almost every athlete knows that they need to eat protein and most athletes supplement their diets with additional protein powders. Yet, 90% of the athletes whose plasma amino acids we’ve tested were essential amino acid deficient.


Essential amino acids are the building blocks of protein.  They allow the body to build and maintain muscle, neurotransmitters, hormones and key digestive and metabolic enzymes.  Research shows that the lack of just one essential amino acid can significantly interfere with these processes.

What I’ve come to realize is that athletes don’t have a protein need; they have an essential amino acid need.  And it’s not how much protein we eat that is critical; it’s the biological value of the protein we eat that counts.

It’s a common belief that one protein is just as effective as another when it comes to rebuilding tissue.  But dietary proteins all contain a different mix of the eight essential amino acids we need.  Therefore their biological value-their ability to be utilized anabolically by the body-differs.

Research indicates that approximately 40% of the protein in high biological foods such as whole eggs, meat, fish, poultry is used by the body for anabolic purposes.  Only about 20% of that found in low biological food such as whey, soy, egg whites, beans and nuts is used for growth and repair.  So, vegetarians and those who consume much of their daily protein as a bar or powder should know that these proteins are not well utilized by the body.


And the problem gets even more complicated.  Even if you are careful to consume only high quality proteins, you still may not be utilizing them effectively.  Stress, age, the use of medications, and/or certain cooking methods can reduce your body’s ability to fully digest the protein you’re eating.

Athletes need to be aware that competition, training, and injury all damage structural proteins.  As a result, the athlete’s body naturally requires greater amounts of essential amino acids for repair, recovery, and growth.  An amino acid deficiency will prompt the body to break down body tissue-primarily muscle-in an attempt to access the missing essential amino acid(s) it needs.

Because of all these issues, we strongly recommend that all athletes use an essential amino acid supplement formula.  These formulas do not require digestion and are almost 100% utilized for anabolic purposes.  While many of us have come to rely or believe protein powders will cover our protein needs-and I was one of them-we now understand that protein supplements are just not as effective as we once thought.

EC: Lastly, you’ve just added an essential fatty acid (EFA) panel.  What are you looking for on this?

RC: Yes, I’m very excited about this new assessment, as the benefits of optimal essential fatty acid status are numerous and it brings us closer to our goal of being able to conveniently and inexpensively assess EVERY key, biological process in the athletic body.

Essential fatty acids perform many physical functions. No cell, tissue, gland, or organ can function normally without them.  Optimal EFA levels are critical to reducing overall inflammation in the body.  They help you work harder and recover faster; they protect your joints, improve your mood and promote deeper sleep.

Our EFA status becomes stronger when we eat foods that are similar to those eaten by our primitive ancestors – lean meats, antioxidant-rich fruits and vegetables, and fats with a high omega-3 to omega-6 EFA ratio.


Over the past 50 years, we’ve developed an unfounded fear of healthful fats.  And we’ve started over-consuming processed fats.  Most Americans consume very little natural omega-3 fats, which can be found in fish, grass-fed meats, seeds and nuts.  Instead, we eat  processed omega-6 fats: corn, soy, canola, and safflower oil.  As a result, we’ve created a very unhealthy omega-3 to omega-6 fat ratio in our bodies.  Recent research has shown that this low omega-3 to omega-6 ratio (Omega-3 index) is not only the most powerful marker of inflammation, but the strongest predictor of sudden, cardiac death.

Last year, when Bend suffered the loss of a 39 year-old world class athlete and the cause of his death was attributed to unknown cardiac cause, I became very motivated to find an affordable, at-home EFA assessment for athletes.  I am excited to say that we now offer athletes the opportunity to assess inflammatory status and their critical Omega 3 index with just a single drop of blood.

EC: Very cool.   Nothing like some cutting-edge stuff to wrap this great interview up!  Thanks for taking the time today, Dr. Cohen.

For more information on Dr. Rick Cohen and Bioletics, head over to their website.  And, don’t forget that they’ve arranged a sweet discount for all EricCressey.com readers.  Enter the coupon code ECCPP25 at checkout, and you’ll receive $25 off the cost of your initial basic or complete panel.

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12 Responses to “A New Paradigm for Performance Testing – Part 2”

  1. Derek Says:

    great stuff, thanks eric!

  2. Mary Says:

    This is the most useful nutrition article I have read in a VERY long time. Thank you for this!!

  3. Lance Goyke Says:

    “Because of all these issues, we strongly recommend that all athletes use an essential amino acid supplement formula. These formulas do not require digestion and are almost 100% utilized for anabolic purposes. While many of us have come to rely or believe protein powders will cover our protein needs-and I was one of them-we now understand that protein supplements are just not as effective as we once thought.”

    I thought he was saying protein supplements (quoted “essential amino acid supplement formula”) were a great decision: almost completely used for anabolic purposes, don’t require digestion, and they “strongly recommend them.” Then he says that they now understand that “protein supplements are just not as effective as we once thought.”

    Could someone explain what I’m missing?

  4. Cris Says:

    Interesting interview.

    I live in the UK and am just getting in to offering similar tests for my clients. I’ve signed up with a company that offers Metametrix tests to the UK.

    I’ve found that gut health (i.e. presence of parasites, candida, excessive unhealthy bacteria) is fundamental to nutrient absorption and immunity.

    Anyone serious about their health, longevity and athletic performance would do well to get their gut health checked out.

    Lance, re Dr Cohen’s point about amino acid/protein powder formulas, it’s my understanding that the amino acid supps aren’t the same as the protein powders. They’re what the powders are formulated from. Taking in the aminos is like getting protein in a purer, less processed form and so it’s more absorbable.

    When you take in protein powders you’re consuming something that’s been processed to a greater or lesser degree (depending on the brand)and hence the quality, absorbability and usefulness is reduced.

    Anyway, that’s my take on it.

    Stay well and happy.


  5. Eric Says:


    Amino acids are the building blocks of all protein (similar to how glucose and other simple sugars are the building blocks of all starches). Eight of them are known to be “essential” (possibly more…). Because, as Dr. Cohen noted, they do not require digestion, they are more readily absorbed (close to 100%) than any other protein supplement you might consider.

    Great stuff Eric and Dr. Cohen! Falls right in line with what many of the greatest minds in nutrition are recommending.

    I remember Dr. Eades saying that if there was only one supplement he could take, it would be magnesium. Deficiency is pretty much widespread throughout most of the population. And, again as Dr. Cohen mentioned, it is very hard to detect as the standard serum test do not show true tissue-levels of magnesium. Proper testing then becomes even more important…

    EFAs are probably one of the most important aspect of health and nutrition. We are only beginning to understand their implications. One of the most important recent findings has to do with the fact that omega 3 and omega 6 actually compete for the same enzymes required for their metabolism, and that their behavior conforms to the “Michaelis Menten” enzyme kinetics, which implies a HYPERBOLIC rather than a LINEAR relationship between omega 3 and omega 6 intake such that consuming more than a certain threshold (often cited as 4%) of dietary calories as omega 6 will put you in the flatter, nonlinear regime of the hyperbolic curve, which means that, exceeding that dose, you can supplement with omega 3 until you are blue in the face, but usually to no avail. You can Google Professor Bill Lands for more info on this fascinating area of research…

  6. Curb Ivanic Says:

    Thanks for letting us know of this Eric. Great stuff. I’ve offered Metabolic Typing to my clients and am just beginning to offer adrenal function testing and hormone testing so I know the value of these types of tests. Dr. Cohen’s mineral status and EFA tests look very interesting.

  7. Yael Grauer Says:

    Good stuff. I started using topical magnesium chloride (Ancient Minerals magnesium oil–though it’s not really an oil) a couple months ago and have noticed a small but significant difference. I switched after reading a study that showed that some forms of oral mg have absorption rates as low as 4%!

  8. Eric Starkweather Says:

    Good stuff, Eric — as usual!

    After reading Dr. Cohen’s website, I’m curious to see how his ideas & recommendations (seemingly derived/descended from Chek) correspond with or contradict what the Precision Nutrition folks (Berardi/ Walsh, etc.) are recommending. Both advocate for blood testing as a path towards maximizing results/performance, but each seems to emphasize different aspects of testing as most important.
    Can you shed any light on the similarities in or differences between the two companies’ approaches?
    How about some thoughts about which client populations might benefit most from each approach?

    Thanks again for the thought-provoking content!!

  9. Benjamin Kusin Says:

    Charles Poliquin figured out the amino acid thing long ago. He always has his guys take ludicrous quantities of them during workouts and they grow like weeds. I don’t take them because I can’t really afford any supplements.
    But this is great stuff, Eric. Thanks for letting us all know about BioLectic and Dr. Cohen. Someone mentioned gut health – that ought to be Cohen’s next project!

  10. Rick Cohen, M.D. Says:

    Few more comments…

    Essential amino acids are critical for endurance athletes as they are along branched chain deficient and generally one or two others. The key point we have found is that protein powders make nice meal replacements but will NOT efficiently enhance growth and recovery.

    GI testing is certainly beneficial but a second line assessment for most. Our key is not to overwhelm with data. Find your diet type add in aminos, EFA, vitamin D and things usual will repair themselves. We are recommending most people favor first whole foods supplements such as green foods with probiotics as opposed multivitamin supplements. John Berardi has actually gone through out testing. He is very committed with nutrition and health and was good for the most part but still had a few holes. This is par for the course. That is the beauty of baseline assessments. Keep it simple.

  11. Andy Says:

    Awesome. This guy should write for T-Nation. 😛

  12. Federico Says:

    I would like to know, because I couldnt find it anywhere, what would be the best ratio of testosterone to cortisol, in order to be in an anabolic state (I dont mean to be very bulky, just lean, hard, strength body and lose the excess body fat). I hope someone could answer me that. Thanks

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