Introduction: Healthy Movements for Human Animals

First installment in a serialized book that provides an evolutionary perspective on exercise

Last week I announced my new book project: Healthy Movements for Human Animals: An Evolutionary Perspective On Exercise. Today I'm sharing the Introduction chapter with everyone as a free preview. Subsequent chapters will be available to paid subscribers only. I expect to publish Chapter 1, "The History of Human Movement," late next week.

---

Introduction: what human bodies are for

What is a human body for? One good answer is … whatever you want to use it for. We're free to use our bodies however we choose—to dance, chop wood, run marathons, sit in front of screens, or stand on our heads.

But there is another way to answer the question about what human bodies are for, and this answer is more informative if we want to understand what kinds of physical activities will make our bodies functional and healthy. This answer is based on an evolutionary perspective which applies to all animals: human bodies, like those of any other animal, evolved to move from place to place within an ecological niche to gather food, find shelter, avoid predators, and survive long enough to pass genes to the next generation. More specifically, human bodies evolved to enable: standing tall on two legs; walking, running, and occasionally sprinting; reaching for and manipulating objects with our hands; jumping, climbing, crawling, and scrambling; carrying loads with our arms; making tools and throwing things. And sitting on the ground for hours, chatting with friends around the fire.

Primal movements

This book is about primal movements—fundamental patterns like walking, climbing, squatting, jumping, reaching, and throwing that our bodies have been adapting to perform efficiently for millions of years. The word "primal" carries two meanings: "essential or fundamental" and "related to an early period of development." Both definitions matter for this book, which makes two interconnected arguments:

1. Primal movements provide the greatest return on investment for exercise. They offer the highest benefit-to-cost ratio in terms of fitness, health, ease of learning, accessibility, safety, transfer to functional activities, and intrinsic meaning.

2. To truly understand human movement, we must examine how it developed through both evolutionary history and child development. By studying how movement patterns emerged across millions of years and how they unfold as children grow, we gain insights into many questions about how to exercise, including:

• which movements are foundational and which are more specialized;

• how different movement patterns relate to each other;

• the order in which to progress movement capacities or recover lost ones.

In short, we get a simple way to make decisions about which movements are essential, which are optional, and which should be approached with caution. Perhaps most importantly, learning about primal movements provides fascinating insight into what it means to be human on the physical level, something that becomes harder to discern as the world becomes more virtual.

The orphaned animal

Consider a brief thought experiment:

Imagine finding an orphaned animal—let's call him Brian. You decide to keep Brian as a pet and you want him to be as healthy and happy as possible. To do that, you need to ask: what kinds of physical activity does Brian need? You know all animals require exercise for optimal physical and mental health. But there are many different ways for an animal to move, and what's healthy for one species might be detrimental for another.

Is it best for Brian to walk, run, climb, or swim? Does he need to chew on hard objects for dental health, or scratch for healthy claws? Are there activities he instinctively craves, like wrestling, hunting, or digging? And how often should Brian be active? Some animals sleep most of the day and sprint around briefly at high intensity, while others move slowly at low intensity for extended periods.

The easiest way to answer these questions is to study the physical lifestyles of similar animals in their natural environment. After some quick research, you learn that animals of Brian's species typically walk about 5 miles daily, occasionally engage in vigorous play and roughhousing with their friends, spend some time climbing trees, and otherwise sit and nap. So you take Brian for walks, let him play with your dog, and build him a jungle gym. Brian thrives with this new program, and thanks you for it. 

Perhaps you see where I'm going here. Like Brian, we humans have been removed from our natural habitat. We need physical activity to be healthy and happy. But we rarely ask: what are healthy movements for human animals? This question could help us design common sense exercise programs with minimal research and analysis, yet we seldom think this way. Why not?

One reason is that discovering the natural ways for humans to move is not so easy when we live in such unnatural environments. To learn how Brian should move, we simply observed other members of his species. But when we observe modern humans, we see them hunched over screens, driving cars, slouching in recliners, or walking in high-heeled shoes. When they exercise, we see a huge and confusing variety of movements that bear little relationship to everyday activities, many of which require coaches or specialized machinery. This offers little insight into the movements that human animals are designed for. In fact, the modern environment makes it easy to forget we are animals at all.

To give us some perspective, three valuable sources of information can help:

First, we can study the physical activity patterns of hunter-gatherers, whose lifestyles more closely resemble our ancestral conditions. This should give us a rough idea of the kinds and amounts of physical stresses that promote health and good function in human bodies.

Second, we can observe how young children naturally develop movement skills in a predictable sequence. This reveals the order in which different movement capacities develop.

Third, we can examine the evolutionary history of different movement patterns—how they emerged, what survival advantages they provided, and how they shaped our anatomy over millions of years.

Together, these perspectives give us more information about which movement patterns are essential, which are optional, and how they all relate to each other. Note that this framework complements rather than replaces other forms of evidence about how to exercise. In this regard, the evolutionary lens serves two key functions:

First, it helps organize the otherwise overwhelming amount of highly specialized information about exercise that we may get from the media. For example, scientific studies tend to focus on narrow questions like the short-term effects of one specific exercise on one specific outcome. Each bit of evidence is like a single puzzle piece, with no indication of how the pieces fit together. An evolutionary perspective provides a big picture that helps us arrange these pieces into a coherent whole.

Second, the evolutionary perspective helps us filter out misinformation, which is often presented in the form of absolute claims that there is an exercise that you MUST DO or MUST NOT DO. Such claims can often be evaluated by simply asking: Does this movement pattern appear in hunter-gatherer societies? Do children naturally perform versions of it while developing? Did our evolutionary history select for the ability to perform it?

Just as understanding Brian's natural behavior patterns helped determine his exercise needs, understanding human evolutionary history provides a simple way to navigate complex exercise questions such as: Should we prioritize strength or endurance? Are machines better than free weights or bodyweight exercises? Should we do short intense workouts or long slow ones? Is sitting really "killing us"? What's the most efficient way to improve posture and build functional movement patterns? 

What this book is (and isn't)

This book isn't suggesting that we need to pretend to be cavemen to be healthy! Nor does it imply that gym-based programs aren't excellent for developing health and fitness. Instead, it's about developing a big-picture, common-sense view of exercise that makes it easier to spot misinformation and make decisions about what kind of physical activity to prioritize.

Further, this book will not provide cookie-cutter recipes or blueprints. In fact, one of the key lessons from studying human movement is its tremendous versatility and adaptability. Humans have the largest movement vocabulary of any animal, and the greatest capacity to thrive in a wide variety of environments. With that in mind, the book is less about providing specific directions and more about offering a broad map of the human movement landscape that helps you recognize where you are and identify directions of interest. Some exploration is necessary!

Picture courtesy of Wikimedia Commons.

How This Book Is Organized

Most of the book is comprised of chapters that address individual movements, such as running, squatting, and reaching. 

Each chapter follows a consistent format, starting with the evolutionary and developmental context of the movements, then offering a variety of exercises at varying levels of difficulty to practice them. We'll also consider similarities and differences between the primal movements as they occur in natural environments versus how similar movements are trained in the gym.

For example, in the chapter on reaching, we'll cover how human shoulder mobility evolved during our ancestors' arboreal phase, the connection between overhead reaching and vertical posture, and the critical role that reaching plays in infant motor development.

In the chapter on squatting, we'll look at how the triple extension pattern of pushing away from the ground has been present in vertebrates since they transitioned from water to land, how this pattern forms a fundamental building block for running and jumping, and how infants learn to squat from the ground up, not from standing down.

The chapters on individual movements are sequenced in a rough order reflecting how these movements emerged on the evolutionary timeline. This structure reveals important relationships—older patterns generally serve as building blocks for newer ones, offering a natural framework for progressing movement skills and regressing them for recovery of lost capacities.

To establish this timeline, the first chapter provides a "History of Human Movement" that traces our physical evolution from fish in water, to amphibians pushing away from the ground, to primates navigating tree branches, and finally to humans walking upright. We'll examine how a similar progression unfolds as babies learn to move. The rest of the book is divided into four sections that reflect the major transitions discussed in the history:

"On the Ground" covers rolling, crawling, sitting and squatting - movements related to the earliest periods of evolution and infant development that form building blocks for more complex patterns. 

"In the Trees" examines reaching, hanging, and climbing—movements that developed when our ancestors lived in arboreal environments. (And no, you don't need an actual tree to practice these!) 

"On Our Feet" focuses on bipedal locomotion: walking, running, jumping, and evasion/pursuit. These movements form the basis for most sports, as well as exercises that build aerobic endurance, speed, and agility. 

"Using Tools" addresses movements made possible when bipedalism freed our hands: lifting, carrying, throwing, and manipulating objects. These tend to promote full body strength and power. 

The final chapter shows how to combine these movements into a coherent program tailored to individual needs, addressing each component of fitness and health. Drawing on evidence from hunter-gatherer movement patterns and activity levels, it presents recommendations about a balanced movement “diet”—identifying essential movement "nutrients" and their optimal “dosage.” These guidelines are compared with contemporary exercise frameworks, epidemiological research, and conventional fitness approaches to highlight commonalities and differences. You can use this information as a way to identify and cure any “deficiencies” in your movement diet, which is the easiest way to make quick improvements.

An appendix covers theoretical concepts from evolutionary biology that provide the scientific basis for the book's approach, including adaptation, natural selection, tradeoffs, and evolutionary mismatches. Here we'll explore deeper questions about what it means for humans to be "adapted" to perform certain movements.

---

A final note before we begin. This book isn't just about making your body more fit and healthy - it's also about finding a sense of meaning in exercise. Modern humans are very interested in self-discovery, but our explorations tend to be limited to highly cognitive domains like literature, history, or movies. We tend to neglect the vast oceans of information about human nature that are embedded in our bodies and revealed through our movements and physical perceptions. 

When you perform movements your body is well-adapted to do —such as swinging from a branch, sprinting across open ground, or jumping over an obstacle—you experience a visceral sense of competence and satisfaction. You’re connecting with patterns of organization that have persisted for millions of years. In essence, you are gaining an embodied understanding of what human bodies are “for.”

Keep this in mind as we explore the History of Human Movement in the next chapter, arriving in the next ten days. To read it, make sure to become a paid subscriber.  [Update - the first chapter has been published.] 

---

Thanks for reading. Let me know what you think in the comments - your feedback will help shape the content of the book.