Intersting post by Tom Venuto

Once an Endomorph Always an Endomorph? (Can Your Body Type Change?)
Tom Venuto

Are you an ectomorph, mesomorph or endomorph body type? To maximize your results, regardless of whether your goal is fat loss or muscle gain, it’s helpful to know your body type and adjust your approach according to your type. But a big question that almost no one has ever answered is, “Does your body type change over time?” If so, then what? Do you have to totally change your nutrition and training again? And if your body type doesn’t change, does this mean you are stuck being a fat endomorph for the rest of your life, doomed because of genetics? Read today’s blog post to find out..

Somatotype is a 3-part, 7-point body type rating scale developed by a guy named Sheldon back around 1940 or so. Ectomorphs are the linear, bony, lean types, mesomorphs are the naturally muscular body types (yeah, the ones we hate!), and endormorphs are the ones with the round body shapes and the genetic tendency toward storing more body fat.

Generally, you have a combination body type, which is why you are scored with 3 numbers (Arnold Schwarzenneger in his bodybuilding prime: think pure mesomorph with the highest score of 7).

The question is, Does somatotype change? this is a very interesting question that has been asked and debated before both by the layperson (often bodybuilding and fitness enthusiasts) and by scientists.


Two of those scientists were JE Lindsay Carter, a physical education professor from San Diego State University and Barbara Heath, and Anthropologist from the University of Pennsylvania.

There was initially a lot of debate and antagonism provoked by the classic Sheldon system of classifying human body types (“somatotyping”), because initially, Sheldon was very rigid in his insistence that body types were permanent and did not change.

However, Heath and Carter proposed that it was plain to see that body types DID change due to normal growth, aging, physical training and dietary deprivation (they cited the Minnesota starvation study, where subjects started out looking somewhat mesomorphic and ended up looking like ectomorphic POW camp victims, literally).

Heath and Carter weren’t trying to dismiss somatotpying, they supported it and wanted to validate it.

However, they wanted to address the shortcomings of the somatotyping method and one of those was the fact that the Sheldon system didn’t accommodate for changes in physique as a result of training and nutrition.

In their voluminous 1990 textbook on the subject, Heath and Carter define somatotype as:

“A quantitative description of the present shape and composition of the human body. It is expressed in a 3 number rating, representing three components of physique: (1) endomorphy, (2) mesomorphy and (3) ectomorphy. The somatotype can be used to record changes in physique and to estimate gross biological differences and similarities among human beings. This method of somatotyping is sensitive to changes in physique over time and is used for rating both sexes at all ages.”


Look at a guy like John Bartlett for example, one of our inner circle contributing authors and an outstanding natural competitive bodybuilder. When you see him today and you ask what is his body type, you would say, “MESOMORPH all the way!”

That’s because today he is ripped and muscular

But if you look at his before picture and ask “what is this guy’s body type” you would say, “Endomorph” all the way!

Well, which is it? Or did his body type change? Clearly, John gained a lot of muscle and lost a lot of fat and looks totally different today. So could we say his body type changed? If we go by current outward appearance, then yes, absolutely.

But does this mean his body type really changed or did he overcome an inherent endomorph body type to achieve where he is now?

Or, to play devil’s advocate here, was he always a mesomorph inherently and he just really let himself go for a while and he was just returning to his normal body type of mesomorph?

These are interesting questions. The Heath-Carter method simply includes body composition as part of the rating scale of a person’s body type and says that you can rate someone based on how they look now. That includes bone structure (which changes little or not at all after adulthood) AND body composition (which can change throughout life). So you could say John was an Endomorph and is now a Mesomorph. Predominantly Mesomorph is his present classification.

However, at the same time, we could say that a person DOES have an inherent body type or set point - a physique that they will gravitate towards in the absence of circumstances or concerted efforts to change it.

I addressed this issue of changing body types versus an inherent (or “permanent” body type) in Burn The Fat, Feed The Muscle (BFFM). The way I explained it is that I said your true body type is what you will gravitate to naturally when you are not in a highly trained state. It’s your inherent tendency. In that respect, you could say somatotype does not change, while body composition does.

In chapter 5 of BFFM I said there were three additional ways to know your inherent body type beyond Sheldon’s scale, which take into account changes in physique due to training and nutrition:

1.How you looked before you took up training (your “natural” body shape)
2.How you respond to training and nutrition (ease of muscle gain or fat loss)
3.How you respond to de-training (how well you retain lean mass and low body fat or how quickly you lose lean mass and gain fat on cessation of training)
If you wanted to make this even MORE complex, we could look at somatotyping by considering not just the outward bone structure and body composition of an individual, but also the metabolic (interior) characteristics

My “Burn The Fat” system of body typing is like a combination of:
(1) Metabolic typing (internal metabolic characteristics like carb tolerance)
(2) Somatotyping (external body shape - linearity or roundness, fatness or leanness)
(3) Miscellaneous other genetic factors.

That would be a pretty good three-part body typing system that covers the concerns about changing body types, individual metabolic types (“carb intolerant types” or protein types, etc), and genetics (which is especially relevant since obesity genes have been identified fairly recently).

I hear criticisms of the somatotyping system all the time, where people say it is not useful. I disagree. Yes, it’s perhaps too crude of a system to base your entire training and nutrition plan upon, but I believe it’s very helpful as a general tool to “KNOW THYSELF”.

In other words, if you are inherently an endomorph and you KNOW IT, then you know darn well what happens when you don’t do any cardio. You know what happens when you cheat four or five times in a week. You know what happens when you slack off. You gravitate towards gaining fat, because that is your body type’s tendency! So you can adjust your training, nutrition and lifestyle accordingly.

If you are an ectomorph, then you know what happens when you skip meals… you don’t gain any muscle! You know what happens when you do too much cardio… you don’t gain any muscle, or you lose some!, etc. etc.

And if you’re a mesomorph…. did I mention…. we hate you!

If you’d like to learn more, chapter 5 in Burn The Fat, Feed The Muscle is about body typing. It’s full of some really valuable and motivating lessons about knowing yourself, your body and your genetics and understanding the importance of taking personal responsibility, regardless of your hereditary predispositions. If you already have the book, it’s worth re-reading periodically.

Tom Venuto
Author, Burn the Fat, Feed The Muscle
Founder & CEO, Burn The Fat Inner Circle