“Performance Blood Testing”: Secret to Success or Waste of Money?

An increasing number of companies are popping up offering to test your blood for all sorts of things – food sensitivities, hormones, vitamin levels, and the maximal rate at which you oxidize jet fuel while running at VO2 max pace. You may have heard of WellnessFX and Inside Tracker; now, Quest Diagnostics is joining the fray with “Blueprint for Athletes”, a new service set to launch in February– and already being marketed heavily to triathletes, with recent sponsorship of Ironman Boulder and Ironman 70.3 Austin.

For the low price of (typically) several hundred dollars (note: pricing for Blueprint for Athletes not yet released), these services promise to give you a personal snapshot of what’s going on inside your body and how it may be affecting your athletic performance.

They’re certainly targeting the right crowd. Endurance athletes love data, and we’re notorious for dropping big money in the name of our sport.

But is it worth it?

Lab Values: What’s Useful, What’s Not, and How to Get the Most Out of Them

Two big issues arise when considering whether lab testing is going to be useful:

  1. Is testing for [insert biomarker of choice here] going to yield valid and actionable data?
  2. Am I going to get additional value out of having an independent company do these tests for me?

I’ll break (1) down more extensively below, but let’s quickly address (2). The most well-validated tests that will tell you something about your overall health and have a possible impact on your athletic performance include things like Vitamin D, iron status, and maybe cortisol and testosterone.

These are all things that your primary care doctor could order for you to the tune of a $10 copay if you have decent health insurance. So why would you ever pay an outside service 20-fold more to run the same tests for you?

collection tubesThe main potential advantages are context and repeatability.

Context: First, if you use one of these services you’ll receive a pretty report card with explanations of what (for example) your Vitamin D level means. If you go to your physician, you’ll come away with a number, and whether it’s within the normal range or not. In many cases this will be enough, especially since a subsequent Google search can tell you more than you ever wanted to know about Vitamin D, health, and sports performance. If you’re (1) less biology-savvy, (2) don’t trust your ability to distinguish real science from Dr. Oz disciples on the interwebs, or (3) just simply don’t want to invest time in doing your own follow-up research – then the personalized educational report is going to be more valuable for you. Again, if you’re willing and able to spend the extra money.

A second, and possibly more convincing reason to use a sports-performance testing service: it could (potentially) allow you to put your values in the context of other athletes. Here’s what most people don’t realize about blood tests: “normal” is calculated based on the range of values typically seen across the general population. For example, hundreds of thousands of people get their Vitamin D levels tested, and the lab looks at all those numbers and determines the normal range is 30-100 ng/ml, with a smaller percentage of people falling above and below that range.

So “normal” does not necessarily mean “ideal” in all cases. And if we were to look at specific sub-populations (example: endurance athletes), “normal” might be different, and “ideal” might also be different. Amongst exercise physiologists, sports medicine practitioners, and scientists, this is a sexy thing to argue over right now, and the general consensus is that yes, there should possibly be different formulas for athletes, but we haven’t quite nailed down what they are yet. In short, more data is needed.

That’s where something like Blueprint for Athletes could come in – they’ll be able to gradually build very population-specific databases of biomarker levels. At a personal level, this benefits you by allowing you to compare your Vitamin D level to not just the normal adult population, but to people similar to yourself in terms of sport, training stress, gender, age, and any other number of variables. If they’re smart, they’ll eventually have some great publishable data on biomarker changes specific to athletic sub-populations, which we can use for future (legal) performance enhancement – but that’s down the line.

This leads nicely into the final potential benefit of utilizing a testing service for your bloodwork: comparison to yourself. Knowing what your inner physiology looks like is only useful if you can work on changing it (through supplementation, diet, lifestyle, sleep, rain dances), and you’ll only know if those changes are working if you re-test (don’t hold your breath on the rain dances). So repeatability is key.

Is performance blood testing right for me?

  1. I wouldn’t pay money for these services if I didn’t intend to (or couldn’t swing it financially) repeat them on a semi-regular basis, say every 3-4 months.
  2. The nice thing is you have the ability to repeat these tests whenever you want. Your friendly family physician isn’t going to want to repeat bloodwork on you every few weeks unless medically necessitated (and last I checked, there’s no ICD10 diagnostic code for “triathlete”).

Even if your family physician is particularly friendly, your health insurance company will say, “ain’t nobody payin’ for that!”.


So employing an outside company to do your lab testing puts you in control. You pay the price in dollar signs, but if it’s within your means, you’re now in the driver’s seat in terms of tracking your own health (what, endurance athletes who like control? Really??)

What is testing, and what is possibly baloney? 

Vitamin D

Since I harped on Vitamin D as an example so far, let’s start there. Vitamin D is simply a steroid hormone produced by your body in response to ultraviolet sunlight. If you’re a pasty white triathlete living at Northern latitudes, there’s a decent chance you’re on the low side of normal – combine that with the upregulation of certain enzymes that affect Vitamin D metabolism1 with exercise, and athletes may be more susceptible to Vitamin D deficiency. So not a bad thing to monitor.

However, Vitamin D is a great example of something where we haven’t yet teased out “normal” versus “ideal” – most docs won’t push supplementation for the average person unless they’re below 20 ng/ml (the range considered “normal” is usually 30-100), but there’s some evidence associating better athletic performance with the upper end of that range (thorough review here). For example, athletic performance tends to peak seasonally at the same time that Vitamin D levels peak (around 50 ng/ml), administering Vitamin D may increase the size & amount of fast-twitch muscle fibers, and – particularly in older adults, as the body’s ability to produce its own Vitamin D declines with age – greater Vitamin D has been directly associated with musculoskeletal performance2.

There are further studies showing a positive correlation between Vitamin D levels and VO2 max3,4,, that supplementing with Vitamin D enhances recovery5, and that Vitamin D may increase testosterone production in men6. However, most of these studies are done in non-athletes, many are correlational and thus don’t prove causation, and much of the nitty-gritty research on musculoskeletal effects is done in rats.

Does that mean that just because you’re not a couch potato (or a rat) that you won’t see some of the same effects? Not necessarily. It just means no promises. And if you do test and decide to take a Vitamin D supplement, you’d be wise to take it with Vitamin K.


Monitoring inflammation seems to make sense for athletes, right? Some of the biomarkers commonly tested for include CRP (C-reactive protein), TNF-alpha, ESR (erythrocyte sedimentation rate), and Interleukins. None of these are terribly specific, but they can provide an overall picture of acute inflammatory activity in your body.

300809832_a9638ca888_nLet’s take a look at the big picture here. Inflammation is a tricky beast – most people think of it as “bad”, but the truth is, you need a certain amount of inflammation to make improvements. Why? It’s the signaling mechanism that triggers your body’s repair-and-rebuild-stronger process. Example: you ride your bike up a 20% grade hill ten times. This results in lots of tiny tears in your quadriceps muscles, which you experience as soreness. All that local inflammation causes your body to send in growth factors, and over the next few days, your muscle fibers repair themselves stronger.

If you go on that bike ride and pop some NSAIDs or immediately dunk yourself in a tub of ice afterward, you’re generally less sore. Great, right? Not so great if you’re trying to get a performance benefit out of that workout. If you block inflammation, you block part of the stimulus to rebuild stronger.

Part of this breakdown-inflammation-buildup cycle is going to be reflected in any inflammatory marker you’re testing for, so it’s important to keep in mind what portion of your training cycle you’re in (and specifically, what you did training-wise around the time you got your blood drawn). For example, during periods of heavy exercise, CRP and TNF-alpha increase, and then trend downward during recovery. Meta-analyses show that this short-term inflammatory/long-term anti-inflammatory effect of exercise holds up.

Chronic inflammation – where you see persistently high levels of circulating inflammatory markers, even during recovery periods – is what should set off red flags, and could be worth monitoring – particularly if you’re a high-stress person who could benefit from some lifestyle changes. Just one snapshot of elevated acute inflammatory markers, however, doesn’t tell you much on its own – you might be overloading your body, you might have just carried rocks across the bottom of the pool the previous day, or you might have a head cold. Basically any physical or psychological stress could produce a temporary bump, which limits the amount of useful information you can get out of these tests.

Iron Status 

You need iron to transport oxygen. Kind of an important thing for exercise. Several tests go into creating a full picture of iron status: serum iron, ferritin (a measure of stored iron), total iron-binding capacity (TIBC), and transferrin (a protein that binds iron in your blood). Iron-deficiency anemia is not uncommon in endurance athletes (particularly women), due to the combination of increased nutrient requirements, faster red blood cell turnover, and small amounts of exercise-induced blood loss through the GI tract and urine. Frank anemia is marked by low serum iron, high transferrin and TIBC, low ferritin, and low hemoglobin.

The jury’s still out on what to do when the picture’s less clear – is endurance performance affected when your iron stores test as low, but you’re not completely anemic? A recent meta-analysis of the literature concluded that we don’t really know – there isn’t good evidence either way. But if you have reason to be concerned about true anemia, get your blood iron tested – this is a fixable problem.

Testing for Food Sensitivities

This is my favorite. Every time someone hands me a list of the 152 things their favorite homeopath told them they were sensitive to, a small part of me dies. So, what do we know about food sensitivity testing?

First, intolerance does not equal allergy. Food allergies are mediated by Immunoglobulin-E (IgE) and cause things like difficulty breathing, throat swelling, itching, and flushing. Then there are non-IgE conditions like celiac disease (which is tested for in your blood by tissue transglutaminase-IgA, as well as intestinal biopsy). On the other hand, the typical battery of food-intolerance testing measures Immunoglobulin G (IgG), which is – as of yet – not considered diagnostic of anything7. Having IgG antibodies to a certain food just signifies exposure, not intolerance – and importantly, positive IgG results are often seen without any corresponding clinical symptoms8.

This is not to say that food intolerances can’t be real. You probably do feel a lot better when you don’t eat XYZ, and there probably is a real reason for it – maybe your particular set of gut bacteria, inflammation in your GI tract, or genetic variants. The point here is not to hate on food sensitivities, but simply to point out that there is no good scientific test for them – so I wouldn’t waste my money.

However, the absence of evidence isn’t evidence of absence. If you’re still curious, before you hand over your credit card, (1) look for labs that use independently verified tests that produce consistent and reproducible results. They should be able to provide you with this info. (2) Get clarification on whether the lab is using antigens from raw or cooked food – they’re different. And you’ll need to know whether to avoid raw pineapples or cooked pineapples. And (3), look for a lab that tests 2 samples and makes sure the results agree.

Testing for Environmental Allergies

Honestly, I hadn’t thought about this one in terms of athletic performance until grilling talking to the Blueprint for Athletes folks about their plans for world domination upcoming offerings. They raised some interesting points. Many athletes race in different parts of the country (or world) than they train in. Theoretically, you could be sensitive to pollen/grass/pollutants that you’re unaware of because they’re not present in your natural habitat. Or maybe you’ve noticed that you really feel horrible at races in the southeastern United States during the springtime, but never really understood why.

If I was going for my KQ on a course filled with pine trees and unbeknownst to me my immune system really hates pine trees, that would be useful information to have beforehand. Would it be at the top of my list of blood tests to spend my money on? Probably not. But an interesting consideration? Sure.

Testing for “Overtraining”

Overtraining syndrome. Everyone seems to be scared of it. Thus, a test – or battery of tests – for “overtraining” is a great selling point for a testing company.

My conclusion: Be skeptical of any single test claiming to diagnose “overtraining”, but don’t throw out the data you do receive.

Most of the tests we’d like to use as markers of overtraining syndrome do give us interesting athletic performance-specific information. Just not about overtraining syndrome. Consider testosterone and cortisol. Your testosterone-to-cortisol ratio drops with greater intensity and duration of training, and goes back up during recovery periods9. Thus, it’s useful for monitoring actual training load, but not necessarily diagnostic of overtraining.


What about creatine kinase (CK)? CK is an enzyme in muscle that’s released when muscle breaks down – i.e., when you train or race hard10. It’s an acute marker of over-exertion, but high levels of CK in your blood don’t mean you’re overtrained. They may mean that you recently completed an Ironman.

Heartwarming Conclusions

As mentioned, I chatted with some of the bigwigs at Blueprint for Athletes when prepping this article. I came away with the impression that they’re smart folks who’ve assembled a sizable crew of physiologists, coaches, trainers, and PhD’s as part of their advisory board, and their hearts seem to be in the right place.

They’ve had individual athletes as well as professional teams beta-testing their services, including the New York Giants (resulting in stories about watching 300lb linemen get into locker room competitions over whose bloodwork looks better when they receive their report cards, which is oddly heartwarming). Just keep in mind that they’re still selling you a service – so just as you would do before upgrading to a carbon fiber bottle cage that’s 2.03 micrograms lighter than your current one, turn off your crazed-triathlete brain for a moment and turn on your rational-person brain. Go back to the original question – is it worth it for you?

Maybe. If:

  1. You want your lab values translated for you.
  2. You’re willing to actually adjust your diet/habits/training/take supplements based on those values.
  3. You have an interest in environmental and food sensitivities, and can maintain a healthy sense of skepticism as far as those tests go.
  4. You have enough disposable income to do repeat testing.
  5. You just need more data in your life.

In which case, let’s hope you’re not afraid of needles.

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About the Author

Adrienne Taren
Adrienne is a MD/PhD in Neuroscience researching stress, your brain & the neuroscience of mindfulness training. She is also a fairly decent triathlete/runner/writer and an average ultra-distance swimmer, if there is such a thing. Visit her blog: http://www.adriennetaren.com/. Follow @SeeSpondyRun

1 Comment on "“Performance Blood Testing”: Secret to Success or Waste of Money?"

  1. Avatar Roberto Garuti | January 28, 2017 at 12:39 pm |

    could you remove the picture of an arrogant white person who doesn’t know anything about socialism? I don’t think it is very appropriate

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