Fuel Efficiency and Overtraining with Dr. Justin Mager

credit: iStock @lunamarina

credit: iStock @lunamarina

If you’ve never tried WellnessFX, you might be wondering: so what can a bunch of numbers really tell me, anyway?

Or maybe you just received your WellnessFX consult, gotten some great recommendations, and want to know more about how everything fits together.

During a recent WellnessFX visit to Krav Maga Worldwide Training Center: West LADr. Justin Mager talked about the science behind the numbers. We’ve already gone through the first two parts of his presentation (Perspective, Process, and Performance and Training Your Fuel System) and are now ready to look at some of the performance markers around athletic ability and overtraining, many of which can be found in our new WellnessFX Performance Panel.

The Glucose Dilemma

To start off, let’s look at a comparison of numbers between a Paleo dieter (top left) and a triathlete carb-loader (bottom left).


The Paleo dieter has a fasting glucose of about 80. According to Dr. Mager, this is ‘pretty good.’ But this number only tells part of the story. We look to HbA1c as an indicator of how blood glucose levels look over an extended period of time (three months, to be exact). Our Paleo eater’s 4.7 reading lines up pretty well with her glucose levels, meaning she keeps her numbers fairly steady. The body favors this kind of stability and consistency, so this is definitely a desirable characteristic.

Now let’s look at the triathlete. She is a very fit individual who just so happens to use carb-loading in her training. Her fasting glucose level is comparable to our Paleo dieter and is also in the ‘pretty good’ range. But what about her HbA1c? As we can clearly see, that has spilled over into the ‘not so good’ category. The one point difference between the two translates to a 30 point difference in blood glucose levels! This means that, on average, our carb-loader has a blood glucose level of about 110 at any given time of the day.

What’s going on here? Even though our triathlete has very good glucose blood levels when fasting, the rest of the time her numbers are pre-diabetic. These high levels also shut off her metabolic gene, which could possibly hinder athletic performance.

Peak Fitness vs Overtraining

Next we look at an Olympian versus a CrossFit Games Competitor to demonstrate the effects of overtraining.


Our Olympian, who competed in London, has good testosterone and a modest amount of sex hormone globulin. The latter is an indicator of overtraining (more of it means less Free Testosterone available to the body for use), but our Olympian is in the safe range. His DHEA, a mild anabolic substance produced by the adrenal glands, also looks good.

Our CrossFit athlete is about 25-30 pounds larger than the other competitor, so off the bat we expect higher testosterone levels. Yet this is not the case: both Free and Total testosterone are significantly lower.

What gives?

Overtraining. It’s very possible our athlete is going a little bit too hard, isn’t giving his body enough rest, doesn’t have the proper nutrition for recovery, or a combination of all three. Further looking at his numbers (for example, cortisol is a strong indicator of stress and overtraining) can inform tweaks to his regimen for greater recovery, bringing his hormones under control, and helping him to reach peak performance levels.

We hope you’ve enjoyed our talks with Dr. Mager. Have any burning questions? Don’t hesitate to ask below!

The posts on this blog are for information only, and are not intended to substitute for a doctor-patient or other healthcare professional-patient relationship nor do they constitute medical or healthcare advice of any kind. Any information in these posts should not be acted upon without consideration of primary source material and professional input from one's own healthcare professionals.