In the 1940s, a University of Houston professor named William Sheldon created the concept that all people belong to one of three body types, or somatotypes.

It is in bold. It is revolutionary. This is complete nonsense.

The whole notion of a three-size-fits-all The classification system was never supported by science. In fact, it has been largely abandoned since its introduction. But this did little to slow the flow of misinformation, which Sheldon based largely on personal observation.

In case you’ve forgotten or sadly lost track of this classic junk science, a brief review might be in order.

What are the 3 Different Body Types?

Like many of us, there’s a good chance you learned about the three somatotypes in a junior high health class. And, on the surface, they probably appear quite reasonable.

Ectomorph

Ectomorphs are described as tall and thin, with a thin waist and little body fat or muscle mass. Gaining weight can be difficult, but losing weight is relatively easy. Think Zoe Saldana or Bruce Lee.

Endomorph

According to Sheldon, endomorphs carry large reserves of body fat and muscle, which makes gaining weight easy and losing weight more difficult. Here, think Serena Williams or Chris Pratt (circa Parks and Recreation).

Mesomorph

Mesomorphs are characterized as athletic, solid, and strong — daywalkers between the other two somatotypes. Let’s go with Mark Wahlberg or Alex Morgan.

Are Body Types Real?

Again, Sheldon’s somatotypes are inaccurate and oversimplify the human body.

“Few people fit perfectly into one of the classic body types,” says Trevor Thieme, CSCS. “Most people are a mishmash of them. For example, you might have the upper body of a ‘mesomorph’ and the lower body of an ‘ectomorph.’ But the ability to classify your body type is not important, because it does not necessarily inform you of what is being done: how your body will respond to training.

So why is it so hard to dispel this fitness myth?

“I think a lot of it has to do with the fact that most people want an easy solution when it comes to fitness and fat loss,” says Thieme. “And the idea that if you have X body type then you should focus on Y type of exercise gives it away.”

But such thinking is backwards, says Thieme. “You have to start with your goal, because that will shape your training program, regardless of your ‘body type.'”

Can You Change Your Body Shape?

Somatotype doesn’t predict response to training, which means you can do a lot to change your body composition. And starting with your goal (say, get fitter), then working backwards to determine your optimal training plan is really liberating.

This means that if you are a classic ectomorph, you don’t have to favor distance running with pumping iron. And if you’re an endomorph, there’s no reason why you shouldn’t train for a marathon if that’s on your bucket list.

The bottom line here is that you won’t know what you’re capable of until you try. But it’s important to know what is in your control and what isn’t.

The role of genetics

To be clear, just because somatotypes are not predictive of performance does not mean that the training field is level. Regardless of your goal or the route you take to get there, you will likely meet others who are traveling there faster or slower than you, because what is written in your DNA is still important.

“There are many factors that we can manipulate to our advantage depending on the goals – training frequency, training intensity, what exercises we prioritize, periodization of programming, nutritional factors – but it is also important to understand that some people to choose the right parents,” said Tony GentilcoreCSCS, owner of CORE, his training studio in Brookline, Massachusetts.

“Some people just look at a dumbbell and they grow. Some people have to fight tooth and nail and exercise many to see the fruit of their hard work,” he added.

The most important factor in choosing an exercise

And that’s the case regardless of your end goal. “But at the end of the day, what ‘work’ is is anything you really want to do and will keep at it,” Gentilcore says.

So tailor your training to your goals, exercise preferences, time constraints, and strengths and weaknesses, advises Thieme. “Your training plan needs to be customized for you as an individual, not based on a body type category that isn’t even designed with exercise in mind.”

The History of Somatotypes

Sheldon doesn’t even catalog body types for fitness purposes. He was a psychologist who posted that it was possible to attach personality features in every body type. He was more interested in how our bodies shape who we are than how they actually function.

Sheldon hypothesizes that ectomorphs are introverted, artistic, and emotional. Endomorphs are cheerful, relaxed, and friendly. Mesomorphs are assertive, strong-willed, and competitive.

If that sounds like poppycock, balderdash, or any other 1940s word for bull effluvium, it is: Sheldon’s entire motivation for his studies has been thoroughly debunked.

“Sheldon’s virulent eugenic views and equation of physique with destiny in the post-World War II years made him unpopular,” according to a 2015 article in Canadian Bulletin of Medical History. “The death knell of his career was dealt by his former female assistant, Barbara Honeyman Heath. Publicly denouncing his methods as fraudulent and his somatotypes inaccurate, he went on to build a successful career transforming approach to somatotyping and participation in projects around the world.”

Why Does the Body Type Myth Persist?

You’d think with that kind of emphatic blowback from the medical and fitness establishments, Sheldon’s idea of ​​three basic body types would have gone the way of the Segway, Zune, New Coke, and Cheetos Lip Balm (yes, that’s a real product).

But the myth of somatotypes is surprisingly strong, as any quick Google search will tell you. For just one of many examples, in London Daily Mail the newspaper asserts, “Scientists say we all fit into three groups (and knowing your shape is key to choosing the right exercise).”

The three-body-types theory gained so much attention so quickly that it soon passed more or less into conventional wisdom, where it has remained ever since. Just like the zodiac, somatotyping works because almost everyone can find traits of themselves in almost every “personalized” assignment.

Sorry if we just ruined astrology for you too.