How we learn to move

In school during lessons I would repeat the same sorts of things, doing lots of example questions with an emphasis on learning the fundamentals and using the best techniques.

but during my undergraduate degree in sports coaching it became clear that these fundamentals, the idea of techniques wasn't quite right.

Spaced repetition, retrieval practice, rote repetition all using the same faulty assumption.

Repetition - not repetition without repetition.

Variability in practice not being a good or bad thing, but an unavoidable thing.

Professional coaches add variability in some wacky ways like Thomas Tuchel, a Premier league football manager.

He made professional football players hold tennis balls during practice [1]

Jason Orchart, a baseball hitting director using hula hoops during practice. [2]

And then Novak Djokovic, a professional tennis player arguably one of the best in the world, practicing by deliberately hitting the ball into the ground before the net. [3]

That's not best technique.

That's not repetition of the same sorts of things.

These are examples of differential learning, the constraints led approach to coaching, and repetition without repetition.

These ideas build from Ecological Psychology.

and for this video, I have spoken with Rob Gray and will be using his book, How we learn to move, as a template for you to follow along.

you can find a link to the book in the description below.

One technique

some people argue there is a best technique or best way to do something.

a position of the body, movement angles or method to solving a problem.

that best technique is what the educator knows and needs to tell the learner.

An incredibly successful basketball coach John Wooden proclaimed 8 laws of learning

Explanation, Demonstration, imitation, repetition, repetition, repetition, repetition, repetition. [4]

Tony Robbins, world renowned life coach saying repetition is the "mother of all skills" [5]

Daniel Coyle in the bestseller book the Talent Code said

there is no substitute for attentive repetition [6]

But as Rob says in his book there is a revolution against repetition.

Its followers not only believe that repetition of the correct technique is not the key to skilled performance and learning to move - they believe that repetition of movement is not even possible. - page 2

Now Robs book focuses on movements, which will be the focus in this video.

but related ideas have been applied to other skills like maths, reading, and most areas of learning.

for this repetition without repetition we actually go back to Nikolai Bernstein in the early 1900.

He watched blacksmiths swing their hammer.

His hypothesis was that the experts would be able to repeat the same movement over and over again because they were experts.

the novices couldn't repeat the movement and missed their target, but.

the experienced blacksmith hit the same spot on the chisel but not by repeating the same movement every time - page 5

• figure 1.1/1.2 page 4/5

As you can see by these early images of motion tracking using cyclography - lights

the expert movement was different.

Jumping forward 100 years and similar results were found in professional potters. [7]

• Figure 1.3

As you can see in this image the hand movement patterns were different.

The squares are different shades, which represent the movement patterns.

There were cultural similarities between the potters but they were all still different

Looking at a professional golf swing one study looked at amateur and professional players [8]

if you average the professional golfers position you get degree angles.

Elbow at 130 degrees, shoulder at 66 degrees away from the body, and trunk rotation of 60 degrees.

but none of the professionals matched that best technique.

The average is useless.

Each player has variation.

The late Ander Ericsson's famed idea of deliberate practice is often associated with repetition. [9]

this type of group comparison the "expert-performance approach" and felt it was the critical first step in understanding the nature of expertise. page 9

but like the golfers, elite swimmers all have different profiles, different coordination styles, different movements. [10]

we can identify different elite athletes in the same sport because of their variation.

not a best technique, this suggests that

variability, not repeatability or repetition, rules the day in skilled performance. - page 12

Variability is everywhere

Variation is everywhere.

heart rate variability or HRV is a good thing.

Our heart beat is not a metronome, there is variaibility between 30-100 milliseconds [11]

Elite athletes often have a higher HRV and lower HRV could be an indicator for cardiovascular disease.

Or just a high-pressure environment.

Our eyes don't stay still when we are fixated on something, they move.

Objects can disappear from our consciousness if they are completely still, something known as perceptual fading. [12]

Similar to when you are wearing a watch, but you are not consciously aware of it.

The change or variation is what we detect.

Traditional views of this variation is an extension from information theory. [13]

There is background noise that is blurring out the signal.

So we need to remove the background noise to understand the signal.

A football study tested this idea.

22 international football players had to make ankle movements blindfolded.

One condition was barefoot, one with socks and boots, and one with insoles that had bumps.

As you could guess the accuracy of ankle movements was decreased when players wore the socks and boots when compared to barefoot.

the noise or clothes was blurring the signal or movement accuracy

then when adding the bumpy insoles you would think that is adding more noise so less accurate movement, but

Adding the bumps to the insole significantly improved performance such that it was slightly better than the level achieved when standing barefoot. - page 17

Let's just emphasize that, more noise, the bumps, showed better movement accuracy.

Variability, noise, helped.

Looking at this figure we can see that adding noise. Specifically random or stochastic noise, helps us see the lines.

• figure 2.1 page 18

Rob quotes Rafael Nadal, another world leading tennis player, who said

every shot is different; every single one [14]

suggesting variation is inevitable, which Rob rounds up nicely by saying.

If I want to produce the same outcome, under ever-changing conditions, I have to use a different movement every time - page 21

Instead of a best technique, ideal movement, gold standard execution we adjust for the context.

We should be developing adaptable movements.

Multiple solutions for the varied problems we may face

Having multiple solutions creates an advantageous state of redundancy. - page 23

Not reliant on one solution.

Practicing with nosie, variability.

and this relates to injury.

you may have heard people say someone got injured for doing it wrong.

or doing it too much.

the solution being moving the right way, or doing less.

but what if, again, it is about variability

overuse injuries related to a lack of variable practice

practicing the ideal movement an indicator of overuse injuries

for runners with knee pain, runners knee, a study added variability to their gait.

how they run.

All participants had clinically meaningful improvements in pain [15]

Adding variability decreased pain.

Boss of the body

When we look at the body, variability is everywhere.

Take my arm for example, there are 7 degrees of freedom.

3 at my shoulder, 1 in my elbow, 1 in my forearm 2 in my wrist.

But then there are the muscle contractions which add more degrees of freedom.

Controlling all of those must take a lot of energy and therefore effort.

Traditional approachs use mental models or a central executive super computer to explain how we control all these degrees of freedom.

Explain how we move.

This super computer tells our body what to do.

Some people think the super computer does it all.

Other people think there is delegation.

A motor program is sent from the super computer CEO down to the body workers [16]

This suggests breaking movements down, helps the degrees of freedom problem.

Separating skills into fundamental movements or techniques.

Training general abilities will just transfer into a persons skill.

Doing vision practice, some reaction time games would help with reaction time in sport.

Doing strength practice would help perform sport specific skills.

Or doing hand-eye coordination exercises would help catching.

The idea being that acquiring a skill is giving the boss all the instructions, the super computer central executive needs.

Once they have all the parts they just put it all together.

But does this mean there is a general motor program for every possible movement and degree of freedom?

There is no real evidence that pulling apart abilities like perception and decision-making, training them out of context, and then putting them back together will actually transfer to improved performance in the overall skill you were trying to improve in the first place - page 36

If we look at a 2019 volleyball study, they got players to follow a sphere. [17]

The idea was that the game would improve players perception and attention to a ball like sphere.

That could then be transfered when playing volleyball.

But as you could guess

Our results have shown that vision training in non-sport-specific context [...] improved cognitive performance, but seems to be less effective for improving sport-specific skills. [17]

and goes on to say

These evidences suggest that environment in which exercises were performed plays a key role to improve perception and action in sport-specific skills, supporting the ecological approach to sport learning. [17]

The FTC has even stepped in with large fines to companies promoting false claims about vision training [18]

for those of you that are familiar with the brain training movement, this is all very similar.

The evidence for brain training is so unconvincing the FTC stepped in again with Lumosity paying $2 million for deceptive advertising. [19]

But if we don't organize movement through a central executive supercomputer with motor programs, how do we do it?

self organization.

other organization like a band conductor happens, but most biological systems are self organized.

A self-organized system is one in which small, minimally intelligent pieces follow local, simple rules by constantly interacting with each other. - [20] page 272

and sometimes very complex patterns can emerge. Behaviour

This research on bird flocks is one example [21]

When testing Dunlin birds in a lab, their reaction time to startling movement was about 40 milli seconds

However, when they were acting in a flock, their reaction time was about 15 milli seconds.

The supercomputer was reacting faster when flying in a flock, compared to a shock movement.

Well the birds were anticipating the movement from the other birds in the flock, but couldn't anticipate the shock movement in the lab.

The Dunlin birds self-organized their movement with the rest of the birds.

Coordinating as a dynamic system.

Instead of a central executive supercomputer CEO boss,

Movement being organized from surroun ding local simple rules,

through the coupling of perception and action constantly interacting with each other

I shared more examples in a previous video linked up there.

the idea here is that organization arises from the birds, no mental model processing needed.

No central executive.

However, if this is true, which those that take an ecological approach believe it is, then training for self-organization doesn't come from instructions or a plan.

We do not need to come up with executive-level plans for every possible situation we might face. - page 41

by constraining environments, adaptable movement solutions can develop which are self-organized.

And these self-organized solutions are more robust to errors.

If there is a change or perturbation, the solution can be adjusted.

One study tested this when sounding out words. [22]

they tugged on participants jaw when participants were saying words like bab.

On the second b when the jaw was tugged the lips compensated to sound out bab.

the synergy of components worked to achieve a goal, not anatomical movements.

the self-organized movement adjusted to achieve a goal, it didn't follow a motor program.

when tugging on the z of baz the tongue compensated

Training an ideal technique for the supercomputer to use as instructions just doesn't seem to explain the data about how we learn to move.

Constraints

Now I mentioned constraining environments.

When I say constraint I am sure most people can think of some.

If you watch children's football they all run around and follow the ball.

you could add various positional constraints to stop them from following it.

a popular constraint I saw used when I played and coached football was the 2 touch rule.

you are only allowed to touch the ball twice. One for control one for pass.

All coaching will use constraints.

But when we think about Brazilian pickup games, sometimes referred to as the nude game [23]

Still talking about football here

There are far fewer constraints.

sometimes no grass, no nets, no lines, no markers, no coaches.

In England I know this as jumpers for goalposts.

When I was out in Uganda helping at a primary school they did the same thing.

Two jumpers on the floor at either end and a ball.

They also played bare foot over the tree roots which I couldn't do, I needed my shoes.

I tried, but kicking a tree root really hurts your toes.

The teams were worked out by the players.

If they were unfair the teams were changed.

This is unstructured, less constrained practice.

However most football coaching is in ordered academies in England, Germany and Spain

using highly constrained practice.

This does touch on early specialisation verses diversification but that is topic for another video.

So constraints are often used to help develop skills which vary across contexts.

Newell in 1986 suggested skills emerge from using constraints not prescribed by the central executive CEO. [24]

A constraint is something that eliminates certain possibilities or options for action. - page 47

Affordances

Which means constraints reduce the degrees of freedom.

Newell suggested 3 types of constraints.

• constraints triangle - figure 4.2 - page 48

Individual constraints like height, weight, strength etc

environmental constraints which we can't really control but we can use and take advantage off.

and the most common type of constraint. The task constraint.

The rules coaches give to players.

If we look at a beginner trying something for the first time they will likely freeze things.

reduce their degrees of freedom.

Stiffen their arms, their legs become robot like.

I know I have said to people in the past to loosen up, but by loosening up there are more degrees of freedom.

more possibilities or opportunities.

coordinating movements effectively therefore requires expertise. learning.

so instead of saying loosen up, I should have helped them learn how to.

adjusted the environment they were in so they could explore different solutions without failing every time for a variety of different reasons.

finding a desirable difficulty.

Helping them not just act like a robot.

and this golfer study actually shows that amplifying errors, or the wrong way, can be more beneficial than telling them the solution or right way. [25]

Some golfers were told to move their body weight backwards - the right way.

Some golfers were told to move their body weight forwards - the wrong way.

Then there was a control group.

direct instruction of the right way, and the control group didn't show improvement.

But direct instruction of the wrong way did.

Results showed that MAE (amplification of error) is an effective strategy for correcting the technical errors leading to a rapid improvement in performance. [25]

and that was with direct instruction.

so what if we create learning environments with constraints, instead of giving them the answer

adding a constraint that exaggerates or amplifies a problem in a movement solution rather than trying to give the athlete the solution to correct it seems to be more effective. - page 54

so we should let them explore solutions in a constrained environment potentially amplifying errors for them to problem solve.

self-organize solutions.

but constraints can give opportunities as well as taking them away.

Lowering a basketball hoop for player to practice.

Restricting vision or hearing encouraging other solutions.

but as we grow and develop our individual constraints change.

In strength and conditioning that is the point.

helping players get faster, stronger, more mobile.

But these changing constraints change how we perform.

think about adolescent awkwardness.

Getting taller changes your point of observation, action capabilities and coordination.

Getting bigger, stronger, older, fitter any development changes individual constraints.

therefore

Moving skillfully involves coming up with new solutions to new problems not just repeating the same old solutions. - page 56

Adding variability in practice encourages learners to find solutions.

That variability can be manipulated by constraints. The constraints led approach to coaching.

But the goal of adding constraints is to encourage learners to explore and self-organize to find multiple solutions.

Not constrain to the point of a single best technique or ideal solution.

Affordance

When considering these opportunities for behaviour, we can't talk about this without mentioning perception.

Traditional approaches to perception break things down into properties like distance, size, slant etc

These properties put together with cues, rules and most liklihoods to make a mental representation.

That is our experience of the world.

The central executive then uses these mental representations to predict what we should do.

This is often called indirect perception something I covered in more detail in a previous video but the ecological approach believes in direct perception.

not perceiving objective properties like distance but relative properties within the organism environment relationship.

We perceive things differently relative to our expertise.

If we struggle, things may seem smaller or faster, but as we develop our skills they seem to be slower or bigger.

we become calibrated

One study looking into this asked how people perceived stairs. [26]

Some were given water at the top after climbing the stiairs some an energy drink.

individuals that chose items with a greater energy density, or more rapidly available energy, estimated the staircase as steeper than those opting for items that provided less energetic resources. [26]

the organism environment relationship altered how these people perceived the staircase.

people perceived the staircase as harder to climb relative to the drink at the end.

this gets me thinking about all the caffeine consumers, maybe it is altering your perception for daily activities.

I mainly drink water, so I do have a bias against coffee and tea but something worth thinking about.

but this suggests that instead of a central executive storing programs that if x then y

we perceive directly.

James Gibson, someone who spoke about direct perception a lot, suggested we perceive affordances.

opportunities or invitations of behvaiour.

For a performer gaps do not look wide, opponents don't look near, and pitches don't look fast. Instead, performers see pass-through-ability in a gap, tackle-ability of an opponent and hit-ability of a pitch. - page 66

our action capabilities and the action capabilities of performers relate the affordances perceived

points of observation and action capabilities unique to each organism - person

so relative properties instead of objective properties.

and these relative properties work in systems.

when we are coordinating we could describe that as a dynamic system

me and mum walking though a door, we perceive affordances for the system. [27]

we twist so we can both get through the door

not adding our shoulder widths to see if they fit

but directly perceiving through action weather, when and how to act.

ie twist together to get through the door.

when people get pregnant their bodies obviously change.

their action capabilies change and so the affordances perceived are different [28]

A study looking at this said

Findings indicate that experience facilitates perceptual-motor recalibration for certain ty pes of actions. [28]

This has been seen in lots of other contexts.

The affordances perceived changes relative to the organism environment relationship. context

Attractors

but if it is always so different, how do we build habits, stable behaviour.

how can we explain expertise, those people finding the multiple solutions.

Well, If we think about drum sticks for a minute they can be in sync or out of sync.

in phase or anti phase

one study looked at the relationship between those sticks from 0 degrees to 180 degrees so there are lots of possibilities [29]

but people struggled hitting the sticks at some of those angles

they got pulled towards 0 or 180 degrees.

but if we look at this figure some were attracted to a third angle, 90 degrees

• figure 6.2 page 80

there were less timing errors at 0, 90 and 180 degrees.

we could call these tendencies, their intrinsic dynamics.

but these attractors, the 0, 90, 180, the stable behaviours happen in more than just drumming.

this figures shows attractor states for walking [30]

• walking 6.3 figure page 81

Walking attractors.png

These attractors encouraging behaviour to stabilize.

Perturbations or interruptions can quickly go back to the stable behaviour. the attractor.

I use this idea to explain why habits are hard to break.

we are attracted to stable behaviours and change or disruption needs to be enough to get out of the attractor dip.

if you think of a sheet, an attractor landscape, attractors are dips, if you fall down the dip it can be hard to get out, especially if the dip is big.

Repellers are then the tops of the dip.

But there isn't necessarily just one dip, one attractor in an attractor landscape. [31]

this is where learning can be explained through exploring the perceptual motor landscape - attractor landscape - sheet.

as players develop skills they become stable behaviours, attractors.

But if the environment changes, that attractor might not be effective.

Rob uses NFL ball throwing mechanics as an example. [32]

Tim used his developed behaviour from college football in the NFL, but in the NFL they are faster than in college, so the movement solution isn't as effective.

the stable behaviour, attractor, wasn't as effective in the new attractor landscape

the task constraints changed.

this is important because it emphasizes that we don't start from nothing.

the tabula rasa or blank slate assumption from Locke isn't quite accurate.

this assumption is used in traditional cognitive psychology approaches

but we don't start with no knowledge, we don't need a loan of intelligence.

like a programmer giving a computer information, we don't get a loan.

Unless you believe we are living in a matrix.

so yes all knowledge is gained from experience, empiricism, but that includes experiences before birth,

and changes in the organism environment relationship.

as learners we want to be efficient, so we use attractive stable behaviours.

human beings are brutally efficient learners. page 85

we are always learning, always exploring solutions through attractor landscapes.

while a learning curve looks nice and might be simpler to explain, it doesn't represent our learning experiences.

• figure 6.5 page 89

Learning is dynamic, non-linear and unpredictable.

Rob suggests educating is actually harder than rocket science.

programmed machines often lead to predictable results.

predicting human behaviour is far more complex,

you might get close, but wether when and how we act is almost, if not impossible to predict, especially when we consider variability.

An effective coach should attempt to design practice environments that foster exploration and promote self-organization rather than prescribing a solution to an athlete. - page 91

This is where teaching games for understanding and the constraints led approach can look very similar.

TGfU (teaching games for understanding) is a learner-centred approach [...] in which teachers are encouraged to design modified games to develop the learner's understanding of tactical concepts. [33]

In contrast

The CLA (constraints led approach) adopts a ‘learner–environment’ scale of analysis in which practitioners are encouraged to identify and modify interacting constraints to facilitate the coupling of each learner's perceptual and action systems during learning. [33]

Another future video topic, but Rob focuses on the constraints led approach or the CLA.

Constraints led approach

when looking at throwing mechanics one study looked at forearm flyout. [34]

the forearm flyout injury is related to the forearm separating from the body too early when pitching in baseball.

most people as Rob says and as I would think, would give direct explicit instruction - don't separate your arm to early

maybe even adding a scare factor.

if you move your forearm out to early you are more likely to get injured

not wrong by any means but if movement is self organized, explicit instruction might be less useful than constraining the environment in a different way.

A tennis study from 2015 looked implementing instructions [35]

"increase your maximum knee flexion by 5%"

"move the point of racquetball contact during your serve 10 cm forward"

although players changed how they moved, there were large errors.

instead of 10 cm they move 15cm

so the instruction lead to more errors.

then for the smaller changes, they were no different than trial to trial variability.

remember repetition without repetition - variability is inevitable

the participants couldn't implement the instruction.

but something else about following instructions is that it doesn't tend to stick.

in the next session they would likely go back to doing what they did before. [36]

following their attracted stable behaviours.

there are theories about controller kids or related ideas, something we spoke about during my degree a lot. [37]

players becoming relient on the coach to give them instructions to follow for how to play.

like when you put your controller down playing the character stops, when the coach stops giving instructions the player stops, get lost about what to do.

of course that is an extreme example but I have seen it in various sports where a team or person coached through lots of instruction looks lost without the coach pointing and telling them what to do.

this isn't to say instruction is bad, or that instruction shouldn't be used.

it should, and needs be used in some cases to communicate.

especially when it concerns safety.

but one study looked at the type of instruction for development [38]

explicit instruction, told exactly what to do through rules.

implicit instruction, not told rules just to play the activity

analogy instruction, using metaphors when guiding participants

all 3 groups improved when compared to the control

Comparing groups showed that the analogy learning group achieved the highest score in the retention test for both motor performance and self-efficacy. Moreover, the implicit group was better than the explicit and the control group.

instruction group comparison.png

you can see in the figure that explicit instruction is better than nothing, but not as good as implicit instruction or analogies.

as Rob mentions when participants were put under pressure

the serving accuracy of the group trained with explicit instructions dropped by nearly 20% while the no-instruction maintained their accuracy at the same level. - page 98

the most effective method, analogies, is what those following an ecological approach try to do.

guide for self organization

not specific instruction, not letting them do it on their own set it and forget it,

guidance through constraints the analogies guiding rather than instructing

when looking to make a change in behaviour we would use constraints.

first, destabilize existing attractors.

the attractor dips are the stable behaviours we want to alter so we shake the landscape around using control parameters.

changing the speed, the space, adding constraints all to destabilize the behaviour.

then we would want to encourage exploration.

know they have been shaken out of the attractor we want them to explore the landscape for other attractors. Other solutions.

We can help that process by amplifying information and affordances.

constraining information simplifying the task helping them self organize a different behaviour.

but then feedback of the different behaviour is important to work out if it effective or not.

most feedback is about results or performance.

knowledge of result knowledge of performance.

But instead, we could look at something referred to as transition feedback.

Instead of telling you whether you achieved your goal or about the underlying processes, it tells you whether your search for a better solution is headed in the right direction. - page 102

going back to the forearm flyout this is an example of constrained practice

ball video

As we watch the throw, the connection ball, the yellow one, falls out as the ball is thrown.

The direction of the ball forwards or backwards is the transition feedback.

it isn't about where the thrown ball goes, the result, how hard or how accurate the ball went.

it is about where the connection ball goes.

if the ball goes forwards the arm is kept closer to the body which as mentioned earlier helps prevent the forearm flyout injury.

so this is using a task constraint to guide self organization of a movement instead of telling the player, keep your arm in.

In team sports small sided games are popular.

this allows for exploration and likely resulting in different stable behaviours.

but of course, if players are only doing small sided games then they are practicing for small sided games.

transition to the larger game would difficult.

in football I have seen this loads, teams training on small pitches, because of money, resources etc

and when it comes to the weekend match they play very narrow and are often quick to play the ball.

Quick ball play is an attractive behaviour from small sided games, but in larger games, the speed constraint is different.

this is where the constraints led approach trys to keep practice representative of the whole

constrained games with a purpose, but the full game should still be practiced.

Differential learning

now some constrained games look laughable.

holding tennis balls, using hula hoops like I said at the start.

well this is differential learning.

The idea is that adding noise, destabilizing the stable behaviours can encourage different, new solutions [40]

In differential learning, the primary goal of practice is to add fluctuations in movement on top of the performer's inherent variability with the intent of increasing the strength of the signal. - page 113

so less about directed constraints and more about exposing variable movements solutions.

Rob uses a buffet example in book.

If we want to change the nutrition of a person from eating just cheese burgers to something more nutritious.

Showing the person a buffet the constraints led approach may say to only eat from the right side.

The side without the cheese burger.

Structuring their exploration.

Whereas the differential learning approach might say, try a bit of salad today, seafood tomorrow and something else another day.

They are designed to randomly pertub the system - page 115

It is about exploring movement space.

Not only is this fun, which is great, but it helps develop skills.

However, when individuals bring lots of fluctuations then we as the educators don't need to add as much.

Again finding the balance for desirable difficulty.

research has shown that the benefits of adding random conditions to practice are significantly lower in situations with more natural variability - page 116

But also, effectiveness depends on an individuals willingness to make mistakes

this is where the culture and social constraints of the learning environment impact the learning experiences.

thinking about psychologically safe environments.

for those sceptical, and healthy scepticism is useful,

This table shows studies comparing the differential learning and constraints led approach to other approaces.

spoiler, most studies found DL and CLA approaches to be more effective. But I recognize this is a biased collection.

Optimal variability

so, what if people become attracted to poor or ineffective solutions?

the fun games resulting in poorer performance.

well again it comes back to variability. An optimal variability.

the degrees of freedom problem is helped during early skill development by freezing movements.

the robot like movements.

the freezing of movements limits individuals solutions.

freezing or self imposed constraints lead to attractors that might be less effective.

solutions that aren't as adaptable to the dynamic environments they will likely find themselves in.

but freezing movements is certainly useful

However, as we develop our skills we should develop the types of freezing

starting by reducing joint range of motion then increasing the range as skills develop.

then we can consider coordination freezes

moving joints at the same time simplifies coordination, reduce the degrees of freedom.

as we develop we can move joints more independently from one another

and this is where each person will find different optimal solutions

what is effective for one, might be less effective to another

a beach volleyball study tried to help novices find optimal solutions by training them to expert players [42]

one group were trained to adopt the gaze of experts the functional group.

look at the attacker then anticipate the point of contact

one group just followed the ball dysfunctional group

and a control group received no training

Results revealed that participants did not learn to adopt the functional control pattern and there were no differences in performance between the groups. - page 131

However when novices were asked to keep their eyes still, the so called quiet eye, it was effective. [43]

constraints on the gaze reduces the degrees of freedom, and was effective.

An optimal movement solution is one that optimally satisfies the current constraints imposed on an individual performer. - page 133

This is covered well in Berstien's concept of dexterity.

dexterity is not confined within the movements of actions themselves but is revealed in how these movements behave in their interaction with the environment, with unexpectedness and surprises - page 133

and so as we develop skills we are developing motor synergies.

our self organized system working to achieve a goal.

Just like the jaw studies I referenced earlier [22]

Those synergies getting tighter and stronger as we continue practicing.

optimal variability sounding very much like desirable difficulty.

too much or too little could be ineffective potentially dangerous when thinking about the relation to injury.

In the book Rob discusses good and bad variability using the term manifold.

if we look at this figure the black line represent an uncontrolled manifold, good variability

• figure 9.6 - page 138

Rob talks holding a tray of drinks.

Maintaining 10 Newtons stops things from dropping.

Any shift along the line the drinks stay on the tray but if there is orthogonal variability

bad variability away from the line, the uncontrolled manifold, then the drinks will fall off the tray

When a performer shows variability in their movement solution it is good when it keeps the performance outcome stable and successful and bad when it does not. - page 139

If we add some labels onto the figure from the book, this might help

• figure 9.7 a - page 140

so effective practice isn't necessarily about reducing variability, but reducing bad variability

Robs basketball study found that they [44]

improved not by reducing all movement variability to as low as value as possible. Instead they restructured there variability - increasing the amount of good and decreasing the amount of bad. - page 142

Creative

This could be where creativity sort of comes from.

Most people in sports would say that the fosby flop for high jump is an example of creativity.

First seen in the 1968 Olympics.

But he didn't just watch everyone going forwards and decide, lets go backwards.

And he wasn't alone in developing this technique either.

Another high jumper named Debbie Brill also developed this technique, but her coach called in "The Brill Bend"

They never met or saw each other but they both developed similar techniques to high jump, after the sand pit was replaced with a mat.

Rob Quotes Debbie who said

There was no way anybody was going to land on their back in sand or sawdust [...] But when I saw the foam mat for the first time, I decided to try something different. - page 146

The task changed, so there were other solutions.

Creativity isn't coming up with an idea then executing it

It arises from a symmetrical, coupled interaction between the individual, task, and environmental constrains faced by a performer - page 147

Creative solutions are not locked in brain ideas

They emerge when a performer is acting and searching for solutions to satisfy the constraints of a task - page 147

through cognitive psychology working memory capacity is often discussed.

the idea that we have a limited capacity in our brain to hold information, and that capacity limits someone's ability to be creative.

smaller capacity would make it harder to hold lots of information for comparison restricting creativity

at least that is the idea

one study testing this split groups of kickboxering novices into working memory capacity groups. [46]

They were looking for creative solutions.

creative meaning original and functional something that is rare or not seen very often

and after comparing groups

There were no significant effects of WM load on creativity outcomes, solution search, or task success. [46]

What is maybe more interesting is that the higher working memory capacity group on average came up with 5 solutions to the problems.

The lower working memory capacity group came up with on average 6 solutions.

High capacity an average success rate of 35%

Low capacity an average success rate of 43%

The results aren't significant but they seem to lean in the wrong direction.

Arguably one of the greatest cricket batsman of all time, Sir Don Bradman, is an creative example Rob uses in the book.

career batting average of 99.94 runs per innings roughly 50% better than any other batsman.

How?

Well an article explains how Brodman's different technique [47]

was not consistent with the coaching manual [...] Bradman’s stance was also unconventional [47]

his creative solutions to the cricket batting problem helped him be original yes, but also functional

what is interesting here is that he developed his skills by hitting a golf ball in his basement with a cricket bat.

not the sort of task constraints you would have seen at a cricket club.

self imposed constraints leading to self organization of unique movement solutions

Becoming good at something does not require conforming to some ideal solution. It involves adapting to the constraints you are faced with. - page 151

Learners should to be given the opportunity to explore.

Now while scripting this I was watching Gotham Chess recap the candidates tournament and he talked about creative ways to play chess. [48]

creative solutions to problems - taking people out of prep [67]

A highly constrained game, with computer based best moves but still the opportunity to be creative

Novelties still happen in the game after all this time.

Original and functional ideas about how to solve a problem.

Cones

Now. Those of you that have played football and likely other invasion games will be very familiar with the odd cone or two.

When I was younger I felt like the coaches needed to use all the cones on the stack when marking out areas and boxes.

but marking out areas with cones is a constraint, but not one that requires much decision making from the participant.

traditional approaches from cognitive psychology would suggest dribbling the ball through a line of cones is developing the fundamental skills.

or running through them is developing a players agility.

developing those blueprints or programs for the central executive CEO to send to the body for execution.

but the skills are different, they are completely different in the whole sport.

unless players line up you wont dibble in and out

unless you are weaving between players, you wont run in and out

and in the whole sport people move, so we should develop skills that have movement

us reacting to players

when dribbling the ball I don't think we would want players looking down, but looking up for options

breaking skills down into their fundamentals relates to the degrees of freedom problem.

but, isolated decomposed skills are not only boring, and potentially belittling suggesting people are uncoordinated or not sporty because they can't do the basics

they often don't represent the whole sport.

An example from my sport, trampoline, you can't do a front somersault until you can do all the fundamental skills.

Front landing, seat landing, back landing, shapes, twists, twists in and out of landings.

some people argue safety, but the progressions for somersaults don't include twisting or most of the shapes.

when you look at people on garden trampolines they can do lots of somersaults but struggle to do other fundamental moves.

the difference here would be task simplification, the progressions, instead of decomposition, isolated moves

In task simplification, the whole movement is always completed - page 158

I am thinking like a forward role as a simplified somersault.

but going back to football there was a goalkeeper study that looked at penalty kicks. [49]

using eye tracking technology they found gaze behaviour was different in coupled and uncoupled tasks

• figure 1.1 page 161

Penalty GK attention.png

in the decoupled the goalkeeper didn't need to move, only say left or right.

The coupled they had to dive.

this supports the idea that perception is for action and perception and action are coupled, not separate.

the organism environment relationship, context, matters

when we talk about the visual system light hits your eyes then goes to your visual cortex.

there is the dorsal stream which goes to the top of the brain, the ventral stream going to the bottom.

Goodale suggested one stream is vision for action [50]

and another vision for perception.

brain damaged patients support this division

one pateint, DF, struggled to verbally say if a line was vertical or tilted but could mail letters into slots with no problem.

this suggests that asking for a an explanation, a decoupled task, one without action, is a different use of vision

the ventral stream as vision for perception.

the dorsal stream as vision for action.

We propose that the ventral stream of projections from the striate cortex to the inferotemporal cortex plays the major role in the perceptual identification of objects, while the dorsal stream projecting from the striate cortex to the posterior parietal region mediates the required sensorimotor transformations for visually guided actions directed at such objects. [50]

we are perceiving organisms but the type of task will impact our perception for action.

for a verbal explanation or a movement behaviour

and those movement behaviours have variability so even with the smallest of changes there can be huge differences.

Take this interaction between a world class baseball hitter and world class softball pitcher. [51]

A bigger ball and moving the mound, where the pitcher stands, a little closer with an underhand throw led to this.

video

Not one contact.

The world class hitter did no better than I could have done with far less expertise in swinging a bat.

Being skilful is a highly specific relationship.

fundamentals are often taught as isolated and decoupled movements.

not a bad thing, because the constraints can be helpful but maybe not the most effective way.

can people learn the fundamentals, by just playing games.

representative practice of the whole activity.

football being the worlds most popular sport we will go back to football,

but Rob does cover lots of baseball research he has done which he talks about in the book.

one football study go 10-11 year olds to practice dribbling, passing and decision making over a 22 week program.

The results showed significant differences in favour of the experimental group in decision-making (p < .000) and the execution of passes (p = .003) after the intervention. However, such differences were not found for dribbling (decision-making, p = .402 and execution, p = .143). [52]

so no isolated drills, no focus on a best technique first, no technical instruction.

just the game.

now fundamentals will likely mean different things to each person as words are relative to the context, organism environment relationship.

but most of the time fundamentals seem to be the basic building blocks.

which falls victim to the that linear assumption of progression.

Linear causality line a to be to c to d instead of multi-non linear causality like legs holding up a behaviour at the top.

fundamental motor skill pyramids like this can be seen in lots of sports going from the fundamental skills upwards.

• 11.3 page 167

and this view often leads to people focusing on specialisation over diversification within that debate.

Specialization is a must to be skilful. But this is not the case. - page 169

Rob introduced me to the term donor sport in book [53]

Donor sport activities are ones which share some of the same athletic movements and affordances required for successful performance in the athlete's primary, target sport. - page 170

but during my degree we spoke about these as assistant or additional activities.

having a primary or target sport, especially at a young is something I am not so sure about, again early specialisation as a topic to explore.

performance v participation also included in this conversation alongside the talent identification debate.

I played football, handball and did trampoline alongside loads of other sports when I was younger.

Athletics, swimming, climbing, canoeing, scouting which involved all sorts of activities like shooting, archery

and then at school when sport seasons came around I played them as well.

Cricket, netball, basketball you name it I have probably played.

And I remember a comment at one of my football matches when I was younger.

How did he do that? one of the parents asked.

I had been pushed over, because I was and am still small, but instead of hitting the floor I did a forward roll and carried on running

something I had learned during gymnastics a few years before.

there are transferable actions between sports

one point I want to emphasize from the book related to the findings of a study [54]

there was no significant relationship between the number of years of sport specific training and proprioceptive acuity suggesting that we don't develop sensitivity to this type of information from traditional sports training. - page 172

Rob going on to say

the best way to develop it would seem to be to encourage young athletes to participate in donor sports focusing on form and body positioning. - page 172

Acquiring expertise

Bringing us to the idea of acquiring expertise

now this might sound picky, and those taking an ecological approach are often accused of being picky with language, but the word acquire

this suggests we acquire things for storage in our brain,

those motor programs the central executive CEO gives out from cognitive psychology

but acquisition of expertise is also associated with skills being automatic

John Wodden the famous basketball coach mentioned earlier was quoted as saying

The importance of repetition until automaticity cannot be overstated [4]

Essentially, as you gain expertise you become autonomous with movement.

because sport is so fast we don't have time to think, we need to be autonomous in our actions.

This is where drills from the military help people repeat the program to become autonomous.

Drilling similar to rote repetition.

but if we look at a video from Ronaldo, a world class football player, arguably one of the best to play the sport [55]

and Ronald, a regular person playing football

they had to score from a cross in the dark

But if we listen to the explanation given for the performance difference

23:28 almost doing math in head 23:55

in that we hear the two traditional components

the internal representation for the central executive is calculating and predicting the future.

then after the command is figured out the skill is executed by the body automatically

this is that indirect perception I mentioned earlier which the ecological approach rejects

no central executive, no internal representations but direct perception

which is used in ideas about direct learning

learning is about attending to things, rather than acquiring the knowledge that absolves us of the need to do so [56]

suggesting we are not acquiring anything, we are detecting information, but then how do we develop expertise?

expertise is all about building a stronger, more effective connection with our environment. - page 178

as discussed in direct learning theory and as I mentioned in the video about Ecological Psychology [57]

develop education of attention

encouraging learners to educate their attention to more effective information

develop education of intention

encourage learners to educate their intention of which behaviour to perform, affordances to perceive and how to uncover possible information

while calibrating the learning experiences

working out how to use the information about given affordances to appropriately perceive, and or perform

A popular model used in skill acquisition research is the fitts and posner model.

I learned about this at school, then sixth form and it wasn't until university that the model was challenged at all.

• figure 12.3

the model maps stages of learning from cognitive to associative, to autonomous

lining up with high to low working memory demands and high to low amounts of practice or experience

but this is a linear model for learning

non-linear pedagogy, the ecological approach, repetition without repetition and other related views about developing expertise disagree with this model

Skilful behaviour is not rote, repetitive, and automatic. It is adaptive, responsive, and intelligent. - page 185

when guiding individuals the idea would be to develop skills not habits

skill involves innovation, whereas habits involve sheer repetition. - page 185

As I have tried to emphasize, variability is everywhere and sport is highly dynamic.

Rob does mention using habits v skill is somewhat loaded

but the idea is to emphasize developing expertise in skills rather than a repeatable best technique habit

Technology in education

when we consider technology, and there is a lot of that nowadays, it is used in learning environments of all kinds.

Artificial intelligence, virtual reality, but then other constraining tools like vision impairment goggles.

As someone that is now half blind, this is something I have been interested in recently.

I am learning to perform moves on a trampoline with completely different individual constraints.

Only 1 good eye. I am also half deaf but I was born half deaf so developed the trampoline moves with those individual constraints.

but occlusion goggles has been used as a constraint to help develop skills such as passing in football [58]

one group used chin up goggles to educate their attention towards the environment

then a control group practicing normally

while receiving the ball they also had to call out numbers so this was a dual task design.

They found that

The group that trained with the Chin Up goggles had a significant decrease in passing errors and in number callout errors while there were no significant changes for the control group. - page 189

so the constraint using technology was more effective for learning

there are other versions some have crystals in which can be activated with a remote blocking the wearers vision.

one study using these goggles tested shooting in football [59]

Pretest-posttest comparisons revealed that the players who had received the goggle training improved their shooting percentages significantly while two control groups did not. [59]

biomechanical analysis of movements has improved dramatically when we talk about the technology that can be used.

motion tracking, speed, angles, 3d renders force data the lot

but how we use the data is an interesting conversation for educators.

one study looked at biomechanical analysis of baseball pitching and told the pitcher some flaws [60]

Data from the second evaluation revealed that 44% of all flaws had been corrected. [60]

However as Rob says

The relatively low success rate here is not surprising given our new view of skill acquisition as it is not really considering the individual differences in coordination - page 193

so although the data looks great and might be really accurate, it might not be all that useful.

when it comes to virtual reality Rob did a study comparing 3 groups. [61]

explicit instruction, self discovery and implicit

as you might expect, in the first game the explicit instruction group where better

they just followed their instructions

by the second game the self discovery were doing just as well, the implicit group improving but not as well

this shows information helps - what a surprise

but as he admits

Then I did nasty. I brought in a new simulated pitcher with completely different tendencies - page 198

nasty maybe but representative.

you might be able to guess what happened.

The explicit instruction group dropped in performance but the self discovery and implicit saw no such effect.

so there seems to be a trade off over time related to how someone learns to move

but something I found interesting at this point in the book was Ironic errors

Ironic errors involve doing specifically what we intend not to do - page 199

If I say don't think about pink elephants you will likely think about pink elephants.

Ironic process theory suggests telling someone not to do something makes it more likely they will

Rob tested this and found that [62]

In the ironic group, the number of pitches thrown in the ironic zone was significantly higher under pressure and there were no significant changes in kinematics. [62]

bringing this all together we could say something like it depends

data has pros and cons, which to me sounds obvious

but for those in high performance data can get in the way

those in participation data can be insignificant

and I personally agree with what Rob says here

there needs to be a coach between the data and the athlete - page 201

Injury prevention

Now earlier I mentioned variability and its relation to injury.

well ACL knee injuries in football are fairly common so there has been research about how to prevent ACL injuries.

One study compared 3 groups looking at non-contact ACL injuries [63]

so no contact from players involved in a potential injury.

They looked at the kinetic and kinematic factors. Biomechanics of how they move.

the 3 groups were linear pedagogy, nonlinear pedagogy and differential learning

Our findings indicate that beginner male soccer players may benefit from training programs incorporating NLP or DL versus LP to lower biomechanical factors associated with non-contact ACL injury, most likely because of the associated increased execution variability during training. [63]

repeating what was suggested earlier, more variability in practice can help prevent injury

maybe using donor sports or other activity as a form of variability, early diversification rather than specialisation

I have heard about rugby players doing ballet to help movement and prevent injury

handball players playing football for variation of movements and resting their arms

with various other crossover sports, some of which lead to sport changes

sprinters going to bobsleigh being one of the more interesting moves, there are obvious transferable skills but not something I would have thought of straight away

the main thing with injury is that in most sports individuals make unplanned movements.

sudden changes

so if most movements are planned in highly constrained practice designs, or drill like repetition

when they play the whole sport, they might not be able to adapt to unplanned movements as effectively resulting in injury

A volleyball study looked at each of these injury points. [64]

Force plate data revealed that power and energy absorption in the knee was significantly higher in the planned condition as compared to unplanned condition. - 206

So planned movements has the potential for higher absorption forces

Motion capture data revealed that there were greater peak knee flexion and internal rotation for the planned movements. - page 206

So planned movements has the potential for higher rotation movements

for knee and hip measures, there was evidence of greater variability in the unplanned conditions.

So unplanned movements has the potential for less similar movements

which all points to fewer risks of injury with unplanned movements.

Similar results have been found with perception-action uncoupling [65]

the coupled group had significant reductions in peak moments of force and muscle activation - page 207

when it comes to bad technique it is clear there is a relationship between technique and injury [66]

but I think anyone could work that out.

from what I have seen and from Rob discusses in the book is that there is more to injury than deviation from the best technique

we will all define bad slightly different so like with much of education, it depends.

something Rob does mention which was discussed during my masters in strength and conditioning was the idea of injury adaptation instead of recovery

Recovery suggests you go back to where you were but as children we are growing fast so will likely grow back stronger

unless of course it is a lifelong change in which case it really is an adaptation.

Much like me losing my sight.

I can't recover it, I can only adapt to it.

If you want to hear more about Robs story he discuses it in his book but he also discuses much of this on his perception action podcast.

for those interested in Ecological Psychology I did a video about the introduction to Ecological Psychology which you can see here