As Graham Scarr writes in Biotensegrity: The Structural Basis of Life, “Part of the problem with classical mechanics is that these laws… were described through experiments on inanimate objects with relatively simple and uniform internal structures. Living tissues, on the other hand, are multiscale composites where each anatomical part is a complex module made from smaller modules nested within its complicated, heterarchical organization… and their physiological interactions conform more to the relatively new physics of soft matter than standard engineering.” (Scarr, 2014, p. 40)

Bones bend. Fascia responds. Tissues under high strain stay supple. Even the most ‘rigid’ parts of the body—bones, tendons—store and return energy like a spring. Structures that would collapse under classical assumptions remain fluid, stable, and alive.

The problem isn’t with physics. It’s with the belief that bodies are best understood as machines.

The Cracks in Classical Biomechanics

Traditional biomechanics gave us a way to understand the body in mechanical terms: bones as levers, joints as hinges, muscles as motors. It made sense, especially in a world reshaped by industry. Bodies were measured, mapped, and modeled like machines. Movement was simplified into vectors and torque. Rehab focused on correcting angles and restoring symmetry. Coaching drills emphasized alignment and force production.

But something never quite added up.

Living tissue doesn’t follow engineering rules. Muscles don’t contract in isolation. Fascia doesn’t behave like rope. And forces aren’t neatly transferred along a single axis—they ripple, radiate, and reorganize across the system. Most importantly, real-world human movement is messy, variable, adaptive. It’s not rigid—it’s responsive.

This gap between the predictable world of physics and the emergent nature of living systems is where biomechanics starts to fall apart.

Why Biomechanics Took Hold

The mechanical view of the human body found fertile ground during the Industrial Revolution. As engineering principles transformed industries, it was natural to apply similar reductionist thinking to biology. Giovanni Alfonso Borelli (1608–1679), often called the “father of biomechanics,” played a pivotal role in this. His seminal work, De Motu Animalium (“On the Movement of Animals”), laid the groundwork for viewing bones as levers and muscles as motors, applying Archimedean physics to human motion with concepts like Class 1, 2, and 3 levers.

At the time, this was revolutionary and offered a seemingly logical framework for understanding complex movements. This approach offered a sense of predictability, which proved useful in nascent fields like prosthetics, orthopedics, and early sports science.

However, it’s crucial to understand that these lever-based models, while offering approximations in highly controlled or cadaveric settings, have never been empirically validated in living, dynamic human systems. We continue to teach these Class 1, 2, and 3 levers as if they explain real-world movement, even though modern science repeatedly shows that the body functions far more complexly than rigid lever mechanics can account for. As Scarr subtly points out, “Even the most fundamental laws of thermodynamics have been revised since their original formulation.” (Scarr, 2014, citing Evelyn 2005 & Beijing 2016).

Classical mechanics isn’t inherently wrong—it’s just profoundly incomplete for understanding life.

From Euclid to Collapse: Geometry, Biology, and the Blind Alley of Biomechanics

The problem isn’t just with the mechanics—it’s with the geometry.

Euclidean geometry, first codified by the Greek mathematician Euclid around 300 BCE, offered a logical and consistent way to understand space. His system of points, lines, and angles was so intuitively “correct” that it shaped the way humans conceptualized reality for over two thousand years. Classical mechanics grew within this spatial system—flat, rigid, predictable—and it was only natural that early biomechanics would adopt it as well.

But biology doesn’t unfold in straight lines.

As Graham Scarr writes, “Classical mechanics thus developed within this spatial system because it was the only one that could be recognized at the time, and its application to biology was inevitable. But it has led biomechanics down a blind alley.” (Scarr, 2014, p. 41; citing Levin, 2002; Noble, 2017)

Living structures aren’t defined by perfect shapes in static space. They are defined by tension and compression, by continuous deformation and dynamic equilibrium. The heart spirals, bones curve and twist, fascia glides and adapts. Nothing in the body is square. Nothing truly aligns.

The continued use of Euclidean logic in biomechanics may help draw diagrams or model force vectors, but it cannot explain how life holds itself together. It cannot model the self-organizing, shape-shifting, heterarchical nature of living movement. For that, we need a different geometry. One that curves. One that responds. One that lives.

Biotensegrity: A New Structural Language

This brings us to biotensegrity, a revolutionary model for understanding biological architecture. The term “tensegrity” was coined by R. Buckminster Fuller, an architect and inventor, to describe structures that maintain their integrity through a continuous tensional network, rather than continuous compression. Think of a tensegrity sculpture: rigid struts (compression) float within a web of continuous cables (tension), holding the shape without touching each other.

Dr. Stephen Levin, an orthopedic surgeon, was instrumental in applying Fuller’s tensegrity principles to biological systems, recognizing that this non-intuitive geometry perfectly describes the human body. As Scarr elaborates, living tissues are “multiscale composites,” where each part is a “complex module made from smaller modules nested within its complicated, heterarchical organization.” (Scarr, 2014, p. 40)

In biotensegrity, bones are the discontinuous compressive elements, ‘floating’ within a continuous, pre-stressed tensional network formed by fascia, muscles, ligaments, and even fluid dynamics. Force is not transmitted through stacked levers but distributed dynamically throughout the entire tensional system. This means that a force applied anywhere in the body is immediately and widely disseminated, allowing for remarkable resilience, adaptability, and energy storage, much like a spring. The body doesn’t stack in segments; it floats in tension.

Heterarchy: Coordination Without Command

A key concept intertwined with biotensegrity is heterarchy. Traditional biological and mechanical models often assume a hierarchy: a top-down control system where the brain dictates every movement, or where one system is inherently more important than another. However, as Scarr’s description of nested modules and complicated organization suggests, living systems are heterarchical.

In a heterarchical system, there is no single “boss.” Instead, all components—from the molecular level within cells, to the cellular, tissue, organ, and musculoskeletal systems—are equally interactive and influential. They co-regulate through complex feedback loops, adapting and influencing each other in a multidirectional, omnidirectional manner. It’s not top-down, nor is it purely bottom-up; it’s a constant, dynamic interplay from the middle to the outside, from the outside to the middle, from the top to the bottom, and from the bottom to the top. This distributed control and mutual influence allow for incredible adaptability and emergent behavior in human movement.

What This Means for Movement

The shift from a biomechanical to a biotensegrity and heterarchical understanding of the body has profound implications for how we approach movement, training, and rehabilitation:

• Coaching: We no longer focus on rigidly “aligning bones” or instructing isolated muscle contractions. Instead, the emphasis shifts to managing tension relationships throughout the entire system, cueing for adaptability, responsiveness, and global force distribution. Critically, this also involves designing movement as behavior aimed at solving problems and tasks. Coaches can leverage task-led constraints to guide the development of motor learning and foster real-world capability, recognizing that movement solutions emerge from the body’s dynamic interaction with its environment—a core tenet of the MovNat philosophy.
• Rehabilitation: Injuries are less about a single “failure” at a joint or muscle and and more about a multifaceted breakdown in the body’s ability to adapt. This can manifest as a disruption within the tensegrity matrix, a lack of sufficient movement solutions (variability) to effectively solve a movement problem, or even influence from lifestyle factors such as cognitive distraction, fatigue, or insufficient readiness for a given task. Treatment, therefore, moves beyond localized fixes to addressing patterns of strain and tension across the whole interconnected system, enhancing motor learning and adaptability, and considering the broader context of an individual’s readiness, fostering systemic resilience.
• Performance: Fluidity, efficiency, and resilience in athletic performance are better understood as the result of distributed coordination and continuous tension modulation, rather than brute force production by isolated levers. Optimal movement is emergent, not simply instructed, and is always contextual to the task at hand.

Closing: From Rigid to Responsive

The human body is not a machine built from predictable parts. It is a dynamic, living system, a “multiscale composite” of astonishing complexity and adaptability. As Graham Scarr, quoting Stephen Levin, reminds us: “Structures that would burst or collapse if constrained by classical laws remain intact.” (Scarr, 2014, quoting Levin, 2006, p. 76).

The shift from the rigid, linear world of classical biomechanics to the fluid, interconnected realm of biotensegrity is not merely an academic exercise. It is a fundamental re-evaluation of how we perceive, touch, train, and heal the body. You’re not a machine in need of calibration. You’re a constellation of living tensions, adapting in real time to the forces of the world.

ABOUT THE AUTHOR:

Brian Betancourt

Director of Curriculum & Performance

A movement strategist and exercise physiologist with over a decade of experience coaching athletes, leading performance programs, and designing educational systems. As MovNat’s Director of Curriculum and Performance, Betancourt is responsible for evolving the brand’s instructional framework, certification pathways, and benchmark systems to meet the needs of a modern, capability-driven audience.

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