The Biology of Movement · The Practice

How movement shapes the organism

In Part 1, we described movement as a practice of freedom: maintaining and expanding the range of actions available to us, while developing our capacity to adapt when something new is required.

But why should movement, often treated as an optional extra, have such a profound effect on us?

Because movement isn’t something that happens to the body. Movement is one of the things that continually shapes the body. Our bodies are adaptive systems. They change in response to the environments we inhabit and the demands we repeatedly place upon them.

Every movement is therefore a kind of biological conversation.

We move.

Our tissues experience mechanical forces.

Our sensory systems gather information.

Our nervous system predicts, coordinates and adapts.

Our cardiovascular, metabolic, endocrine and immune systems respond.

And over time, these repeated experiences influence what we, as an organism, become.

The body is always listening

A useful way to think about the body is that it is constantly asking:

What does my environment require of me?

If you regularly lift heavy things, your body has reason to maintain the capacity to produce force. Spend time hanging and your tissues and nervous system repeatedly experience the demands of suspension. Move through large ranges often enough and those ranges become part of the environment your body is adapting to. Balance, and your nervous system receives continual information about orientation, position and instability. Sprint, jump and decelerate, and your tissues meet forces and rates of loading that walking cannot provide.

The body doesn’t maintain every possible capacity equally. It allocates resources according to experience.

This is one biological foundation of use it or lose it. But it is also the foundation of something more positive:

Use it, and give your body a reason to keep it.

Adaptation is not just muscular

It is easy to think about adaptation as something that happens to muscles. But movement is an experience involving the entire organism.

Muscles adapt. They respond to loading, velocity, duration and metabolic demand.

Tendons adapt. They respond to repeated mechanical loading and help transmit and store force.

Bones adapt. Mechanical loading influences bone remodelling and helps determine the structural properties of bone.

The cardiovascular system adapts. It responds to changes in the demands placed on circulation and oxygen delivery.

Metabolism adapts. Muscle activity influences glucose regulation, mitochondrial function and a range of signalling processes throughout the body.

The nervous system adapts. Perhaps most importantly for movement practice, it continually changes with experience. Connections strengthen and others weaken. Sensory representations change, motor maps reorganise, and coordination becomes more efficient. New skills become easier to learn when the nervous system already has a wider range of related possibilities to draw from.

Movement is therefore not simply “training the muscles”; it is training an interconnected biological system that is far more intelligent and prepared for movement than our brains give it credit for. Build the capacity of individual parts, develop coordination and ease, use it regularly, and trust the innate intelligence of a body designed for movement to do the rest.

The nervous system is plastic

Neuroplasticity is the capacity of the nervous system to change in response to experience.

This isn’t a special phenomenon that occurs only when we learn a new language or recover from an injury. It is happening all the time.

Every time we practise a movement, we provide the nervous system with information about:

what matters
what is possible
what is safe
what requires attention
what can be automated
what needs to remain adaptable

Repeated experience can strengthen particular neural pathways and make particular actions easier to coordinate. But learning also involves removing or weakening connections that are less useful.

This is where use it or lose it becomes physiological: the nervous system is continually editing itself.

Some of that editing is physical. Connections that are repeatedly used are strengthened and stabilised; others weaken, and some are removed altogether. Motor learning reorganises whole networks to better accommodate what you do most often.

Our nervous system is not built to preserve every possibility indefinitely. It adapts to the experiences we give it, and our movement environment is a central part of the information from which it constructs itself.

Attention is the currency

If the nervous system adapts to experience, the obvious next question is which parts of an experience it adapts to. Not all of it, and not equally.

Attention is the currency of the nervous system.
Where you place it is where you adapt.

This is why two people can do the same exercise for a year and end up somewhere different.

Take a pancake: sitting with the legs wide, folding forward. I teach it as a hip movement. You hinge at the hip, tilt the pelvis forward, and use the hip flexors to actively pull yourself deeper. Near the end of your range it is difficult to connect to those muscular pathways, so I cue it from positions where it is easier and build towards the harder ones.

Some people can readily put their attention there, on the hip. Others cannot yet connect to that pelvic rotation and end up creating the fold shape mainly from the spine flexing.

Both groups get deeper in the shape over time. But the first group learns the pathway. They can find the hip movement, produce it deliberately, and keep improving because they are training the action that can create a deeper fold. The second group tends to reach a limit and then try to solve it with more spine, because that is the only route they have learned.

The exercise was identical. What differed was where the attention went, and that is what each nervous system adapted to.

The same is true of how much you appear to care, which is why I like to say: “play as though your life depended on it.” Your nervous system does not know that you are only catching a stick. It knows how important you appear to think this is, and allocates accordingly. Going through the motions gets you part of the way there. It does not get you all of it.

From capacity to access

This leads to an important distinction. A person can possess a physical capacity without having easy access to it.

Consider a deep squat.

Perhaps the joints have enough mobility and the muscles, tendons and ligaments tolerate the position. That is what build develops, and it operates on the level of body tissues.

But the nervous system also needs to perceive the position, coordinate the necessary muscles, regulate balance and predict the sensory consequences. That is control. Even once you can hold the position, it may still require far more effort than it should, leaving nothing spare for anything else. That is the second half of control.

And even if all of that is present, you may rarely use the squat outside of training it specifically. It isn’t part of your spontaneous behavioural repertoire. That is use and it creates access.

The three are described in full in Movement as Freedom. What matters biologically is that they can diverge. A person may have plenty of tissue capacity and very little control. Or plenty of both, considerable refinement, and almost no access.

Understanding which one is limiting us can change how we approach training the movement. Sometimes we need more strength, sometimes more range. Sometimes we need coordination, sometimes refinement. And sometimes we need exposure and confidence. And sometimes we simply need to use a possibility more often. We don’t have to fix every limitation before we move. We can move while we build, improving coordination and making better use of the access we already have.

At Totum, we build these different layers simultaneously, and having an understanding of them can help improve your mindset and approach.

Evolutionary health and the movement mismatch

There is another reason this matters.

The human body evolved in natural environments that required a remarkably broad range of physical behaviours.

Walking long distances.

Carrying.

Climbing.

Squatting.

Getting up and down from the ground.

Navigating uneven terrain.

Manipulating objects.

Reacting to unpredictable environments.

Occasionally running, jumping, scrambling and climbing.

Not necessarily as exercise. As life.

Modern technology has changed this dramatically. We can now obtain food without walking. Travel without carrying ourselves. Communicate without moving. Work while sitting. Live on smooth, predictable surfaces.

This is an extraordinary achievement. But it creates an evolutionary mismatch. The environment has changed faster than our basic biology. Our bodies, right down to our DNA, still respond to mechanical and sensory demands according to biological rules that were established long before modern life.

So movement practice can be understood partly as a way of deliberately reintroducing biological signals that modern environments have reduced. Not by attempting to recreate ancestral life.

But by asking:

What capacities might a human organism benefit from continuing to maintain?

Variation matters

This is why movement variety matters so much.

Doing the same thing repeatedly is useful. Repetition develops capacity. But variation exposes the organism to different demands.

Consider hanging from a bar. The simplest version:

reach up → hang → let go

That alone gives the shoulders, hands and connective tissue a signal they rarely receive in modern life.

But now change the context.

Hang from one hand.

Hang and rotate.

Shift your weight from side to side.

Draw your knees up.

Change your grip.

Hang from something thicker than a bar.

Hang from something you can only just hold.

Swing, and control the swing.

Move hand over hand.

Let go and catch again.

Get from hanging into standing without using the floor the way you usually would.

Now the nervous system has to do more than reproduce a known solution. It has to adapt.

This distinction, between repetition and exploration, is central to my approach. We need both.

Repetition builds reliability.
Variation builds adaptability.

The session is a poor witness

How a session feels can be a poor guide to what you got from it. Practise one simple thing repeatedly and it gets smoother. You leave feeling capable, and you should: you performed it well.

Change the context, vary the problem, and keep bumping into things you cannot yet organise smoothly, and the session can feel worse. You leave less certain than when you arrived.

The smooth session measured your performance that day.
The messy one is building something.

A comfortable session can feel good. But comfort is a weak signal of learning. When a movement is genuinely new, it can feel awkward, effortful and confusing. That isn’t the practice going wrong. It is more likely the feeling of a nervous system working out a solution it does not yet own.

This does not mean harder is better. If you practise far beyond what you can currently organise, you will recruit tension, compensation and frustration, and your nervous system will learn those too.

The useful zone is where you can still work the problem: enough difficulty to demand adaptation, enough control to keep solving it. It often feels like effort with a thread of confusion running through it. Working in that zone is the loop in action. Learning to find and stay there is a “muscle” of its own, and the more you practise it, the easier it becomes to learn something new.

The organism as an evolving possibility space

Perhaps the most useful biological metaphor is not the body as a machine, that was debunked a long time ago. It is the body as a possibility space.

At any moment, your body has some things it can do easily, some things it can do with effort, some things it can do only with practice, and some things it currently cannot do.

That space is not fixed. Training can expand it and inactivity can contract it. Injury can alter it, age changes it, environment changes it, and learning reorganises it.

And movement is one of the ways we deliberately participate in that process. This is why we don’t only want to become “fit.” We want to remain adaptable.

A resilient organism is not one that can resist all change. It is one that can change in response to change.

Movement as biological agency

We cannot control everything our bodies become. But we can influence the signals we give them.

We can choose to expose ourselves to:

force
range
speed
instability
precision
coordination
novelty
play
effort
recovery
exploration

Each provides a different kind of information. And over time, those experiences become part of the organism.

This is the deeper biological meaning of movement practice:

We are not simply maintaining a body.
We are participating in its continual construction.

Movement is one of the ways we tell our biology:

These possibilities still matter.

And when we deliberately explore unfamiliar possibilities, we tell it something else:

The world can change. Stay adaptable.