Bodybuilders who have overcome controls steroids and not only differ in the amount of muscle mass they have obtained. For those who are interested in knowing the science of being a true natural bodybuilder, this article will shed some light.


Basically, there is a physiological limit to the amount of muscle that a human being of a certain height can accumulate without taking drugs of any kind (steroids, growth hormone, pro-hormones, etc.) (Kouri et al. 1995). Surprisingly, there is both subjective and objective way to determine if a builder is natural, and in addition, if aesthetic.

Aesthetics, for the purposes of this article, it is defined as being provided, symmetrical and have a good balance between muscle groups (Hansen. 2005). The problem with this definition is that it lacks formulas that provide a clear canon.

Although there are many bodybuilders standards, there are two sources that I consider of utmost importance for natural bodybuilding. They are the book “Natural Bodybuilding” by John Hansen and the book “Super Athletes” David Willoghby of DC personal trainer. In “Super Athletes” Hansen indicates what should be the action of certain body contours and Willoughby does the same, based on bodybuilders champions pre-steroid era.


P478The standard criteria for identifying natural bodybuilders is the rate of fat-free mass (FFMI) (Kouri et al. 1995). This has been used in other investigations and has application even among different age groups (Kyle et al., 2003; Schutz et al., 2002). However, our particular interest are only bodybuilders.

To my surprise and fascination, there is a study that sets the gold standard for detecting drug use among bodybuilders (Kouri et al. 1995). The data used to tabulate the FFMI bodybuilders partially comes from the pre-steroid era.

The data is first extracted from 84 drug users and 74 natural bodybuilders, and then were added to the analysis all winners of Mr. America during the years 1939-1959. It was concluded that there is a limit of 25 in the FFMI for natural athletes (Kouri et al. 1995). However, it should be noted that some of the Mr. America exceeded this value, being the highest of 28 and 25 the average FFMI.

It was argued that genetics and the margin of error with the actual fat percentage may have contributed to the above 25 values (Kouri et al. 1995). Based on the data, however, we can say that anyone with more than 25 FFMI is a genetic privileged and belongs to the elite of natural bodybuilding.

It might be possible to get a FFMI 30 being natural, but this tiny group of individuals represent the elite as stated before,. For most, the limit of 25 is the reference. Accordingly, if someone exceeds a FFMI 30, we should be very skeptical if it claims to be natural.

Finally, it should be noted that the maximum values of FFMI are based on state of competition bodybuilders (3-5% body fat), and for individuals who are overweight or more overweight the formula becomes invalid (Kouri et al. 1995). This formula is based on subjects as defined and large at the same time as possible.

You can use the following calculator to estimate the FFMI the greatest possible accuracy in the data (only valid for men) still needed:


FFMI men:

16-17 Well below average

18-19: Average

20: Above average

21: Noticeably on average

22: Excellent

23 to 25: Superior (Inalcanzable for ordinary adults but accessible to 10% of natural bodybuilders)

26-27: Some natural bodybuilders could reach this level, according to genetic

28-29 It is possible but very unlikely to reach this level without drugs, as science has shown that natural bodybuilders never exceeded 28.

30 or higher: This person is not a natural bodybuilder, according to common sense, but also according to science.

I’ve always admired bodybuilders 70s rather than current. For example, some of my favorites were Arnold Schwarzenegger and Frank Zane. The interesting thing is that my initial thoughts on the natural appearance of the body were confirmed by the FFMI.

State of competition Frank Zane measured 1.75m and weighing 81.5 kg, and its FFMI 25.3.For Arnold, it was 28.7. When I introduced some of the past winners Olympia FFMI both were much higher than 30. The irony is that both Arnold and Zane were my favorites for its aesthetics.

We have therefore a numerical target value confirming subjective perception. In short,individuals with values above 30 FFMI lose the aesthetic appeal and the natural look.

As for the controls to detect the use of steroids, have some shortcomings:

  • People can learn to lie and beat the polygraph.
  • There are many drugs and masking substances in the body during the controls, even blood tests and urine may appear normal although steroids are used.

However, although the findings of this study were preliminary, the FFMI can be a useful tool in conjunction with polygraph testing and steroid use. In other words, a natural bodybuilder would be one that would overcome the 3 tests (polygraph test steroid test FFMI).


Although it is possible that even then a bodybuilder drug user pass the tests, at least its FFMI would equal chances to the point that drug users could be defeated by a natural in a bodybuilding competition. In fact, I have had news of similar events, when a natural competed in an event uncontrolled substances.


Employing the FFMI, whether natural or not individual, we help to level the possibilities. At this juncture, muscle mass and other aspects of bodybuilding as symmetry, proportion and stage presence are equanimously applied by judges (Gaines, 2001) are equal.

Not surprisingly scientific research has shown that the only difference between natural bodybuilders and drug users lies in the amount of muscle mass (D’Antona et al. 2006). So the question without profit ofender- is it really worth exposing several health problems only by the single component (muscle mass) that make us different from a natural?