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Fascia and motor control 

Eur J Transl Myol 29 (3): 185-194, 2019 

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Fascial organisation of motor synergies: a hypothesis 

Alessandro Garofolini (1), Daris Svanera (2) 

(1) Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia; (2) 

Independent researcher, Brescia, Italy 

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License (CC BY-NC 4.0) which permits 

any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. 

Abstract 

In the field of biomechanics and motor control understanding movement coordination is 

paramount. Motor synergies represent the coordination of neural and physical elements 

embedded in our bodies in order to optimize the solutions to motor problems. Although we are 

able to measure and quantify the movement made manifested, we do not have confidence in 

explaining the anatomical bases of its organisation at different levels. It is our contention that the 

flexible hierarchical organization of movement relies on the fascial structurers to create 

functional linkages at different levels, and this concept attunes with the neural control of 

synergies. At the base of movement organization there is a (somatic) equilibrium point that exists 

on the fascia where the neurologically- and mechanically-generated tensions dynamically 

balance out. This somatic equilibrium point is at the base of postural control, afferent flow of 

information to the nervous system about the state of the muscles, and of the coordinative pre-

activation of muscular contraction sequences specific for a synergy. Implications are discussed 

and suggestions for research and clinical applications are made. 

 

Key Words: Motor control, degrees of freedom, myofascial continuity, movement coordination, 

muscle spindle. 
Eur J Transl Myol 29 (3): 185-194, 2019

 The anatomical elements involved in the organisation 

of motor synergies, and voluntary movements in general, 

are still not clear for several reasons. First, the difficulty 

in explaining movement organisation which is inherited 

in the traditional anatomical understanding of the human 

body, often seen as the sum of the parts that compose it.1 

Second, classical anatomy has been based for centuries 

on the concept that we can extract a part, we can study 

how it works by breaking it down to its components, and 

once we have all the parts extracted and analysed, the 

sum of all those parts will explain how the human body 

works.2 Although this view has been challenged over the 

years,3,4 our understanding of function is still biased by a 

segmental anatomical knowledge of our body. This is 

manifest in biomechanical models of the musculoskeletal 

system that represent muscles as independent units 

connected to the bones at their origin and insertion.5,6 In 

this perspective, muscle forces are transmitted serially, 

and the torque developed around a joint depends only on 

the muscle’s torque arm geometrical configuration. 

Movement patterns are therefore, analysed through a 

linear framework of isolated muscle groups, based on 

singular muscle attachments and isolated joint actions. 

However, complex movements result from simultaneous 

interaction of multiple parts of many human systems and 

denying this may overlook the complexity of the human 

system and limit our understanding of movement 

organisation. An alternative view regards the human 

body as a tensegrity-like network,7 with the connective 

tissue (fascial structure) acting as linking component.8 In 

this view, the direct morphological continuum between 

muscles and fasciae is at the base of the mechanical 

interactions between agonist muscles (i.e., producing the 

same movement at a joint) as well as between 

antagonistic muscles;9 this tensional continuous 

coordinates intermuscular and extramuscular force 

transmission.10 The central role of the fascia in movement 

coordination has been shown in a series of 

experiments,10-13 where muscle tendons were transposed 

(insertion shifted to antagonistic location) and movement 

recorded. The assumption that a muscle would change its 

action after tendon transposition was rejected: muscle 

still conserved its function due to the orientation of the 

connective tissue. This proves the controlling function of 

the fascia over muscle activity. 

While evidence consistent with the role of synergies in 

movement organisation is growing,14-17 much work is 

still needed to delineate their anatomical basis.18 

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Although it is relatively easy to observe a synergistic 

movement, explaining the anatomical structures 

responsible for generating and organising such a 

movement is not an equally easy task. Research has 

focused on whether synergies have a neural origin,19 or 

they are a product of experimental or biomechanical 

constraints.20 It is believed that basic foundation of 

covariant muscle combinations (motor primitives) are 

modulated by the central nervous system to perform 

complex motor behaviors,21,22 that is, information is 

encoded into motor neurons (either by genetic design or 

learnt through experience) so that higher neural discharge 

rate is present in a preferred movement direction.23 

However, by varying the length change of muscle groups 

individually, synergies between muscles emerge as a 

result of non-neural coupling,20 showing that the central 

nervous system does not need to control a group of 

muscles to observe muscle activation.24 Synergies are 

difficult to investigate because it is still not completely 

clear how the nervous system combines synergies, or 

how and where (anatomically) the synergies are scaled 

and weighted.25 In our hypothesis, both neural and non-

neural control of motor synergies coexist and they are 

linked through the fascial system. Aim of this review is 

to present possible anatomical explanations of the 

phenomena – synergies – described and quantified in 

motor control. We will look at synergies and their pillars 

from a fascia point of view, giving evidences for an 

alternative way of thinking about movement 

organisation. Before proceeding to examine synergies, it 

is important to define the fascial anatomical organisation, 

and its physiological meaning. 

Fascial System 

Fasciae are classified as a proper connective tissue that 

are dense and regular,26 made of collagen and elastic 

fibres; the former gives structure while the latter gives 

elasticity to the tissue. At different levels, the type of 

fibres and their orientation will define the role of the 

connective tissue. In this section we will illustrate the 

muscular fasciae (or deep fasciae); for a comprehensive 

review of the cellular characteristics of the fasciae see 

Stecco C, Macchi V, Porzionato A, et al., 2011 and 

Stecco C. 2014.26,27 The muscular fascia (Figure 1) is 

divided in (from inner to outer layers): 

1. The endomysial fascia surrounds muscle fibres; its 

collagen fibres are directly connected to the basal 

lamina overlying each muscle fibre.28 The motor 

(alpha axon) endplate terminates on the endomysium. 

The outer layer of the endomysium is made of loose 

connective tissue ensuring gliding between muscle 

fibres.  

2. The perimysial fascia surrounds secondary bundles of 

muscles. With a small inner layer (connected to 

endomysial fascia) of loose connective tissue, an 

external layer of gliding, and an intermediate layer of 

 
 

Fig 1. Representation of the muscular fasciae. Aponeurotic fascia is not displayed as it will contain all muscles with 

similar directional meaning.  
 Reproduced with permission from Handspring Publishing Ltd, taken 

 from "Fascia: what it is and why it matters" by D. Lesondak (2018). 

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collagen fibres, the perimysium has high resistance to 

traction,29 The ends of the neuromuscular spindle 

insert on to the perimysium.  

3. The epimysial fascia surrounds the individual 

muscles (i.e. bicept brachi); it is a fibrous-elastic 

tissue closely connected to the muscle. Multiple septa 

exist connecting the epimysial fascia to the 

underlying muscle fibres and the perimysium, and the 

overlying aponeurotic fascia. The intermediate layer 

is constituted by about 20% of collagen fibres and 

elastic fibres; those give the ability to the epimysial 

fascia to resist tractions.29 

4. The aponeurotic fascia is the outermost component of 

the muscular (deep) fascia. It is composed of two (or 

three) independent layers of about 1% elastic fibers 

and 80% collagen fibres arranged longitudinally, 

transversally, and obliquely.30 Each layer has parallel 

collagen fibres separated from the underlying one by 

a layer of loose connective tissue that allows collagen 

fibers to glide freely one onto the other.27 The 

function of the aponeurotic fascia is to transmit 

forces, and thanks to the different orientations of the 

collagen fibres, the aponeurotic fascia can transmit 

forces in any direction. 

Somatic Equilibrium Point (SEP)  

Only 70% of the extrafusal muscle fibres (those that lay 

outside the muscle spindle) have a tendinous insertion, 

while 30% have a fascial insertion,31 which allow muscle 

tension to be transmitted onto the fascia at the level of the 

epimysium.29 Similarly, the intrafusal muscle fibres 

(those that lay inside the muscle spindle) tension the 

perimysium. Thanks to the bindings between different 

layers and their collagen nature (see previous section), a 

somatic point of equilibrium is formed on the epimysium 

that represent the equilibrium between alpha motor-

neurons’ activity (extrafusal muscle fibres activation) 

and gamma motor-neurons’ activity (intrafusal muscle 

fibres activation). We hypothesise this neuro-mechanical 

system to be the anatomical base for basal muscle tone 

and muscle synergies. We acknowledge that 

computational models already exists for alpha-gamma 

coordination,32 and they comprised physiologically 

realistic spinal circuitry, muscles, proprioceptors, and 

 

 
 

Fig 2. Motor synergies characteristics. 

Movement intention Premotor area Action Plan          Task

 Elemental variables – (Muscle Spindle)

 Elemental variables – (Muscle and segmental joint)

 Elemental variables – (Sequential joints)

 Elemental variables – (Limbs in diagonal movements)

 Elemental variables – (Limbs in spiral movements)

 Action on the environment

Movement 

organisation

Spinal cord

Spinal cord

Spinal cord

Retinacula

Retinacula

Epimysium

Multidirectional 

movement

 SEP in spiral organisation

Synergy- 4

                                 Task-4 (Regulation of Limbs motion                                    

                                in three planes of the space)

Aponeurotic 

fascia

Aponeurotic 

fascia

Bidirectional 

movement

 SEP in diagonal organisation

Synergy- 3

                                 Task-3 (Regulation of Limbs motion                                    

                                in two planes of the space)

Unidirectional global 

movement

      sequential SEP

Synergy- 2

                                 Task-2 (Regulation of Limb motion                                    

                              in one plane of the space)

Aponeurotic 

fascia

Ia & IIa

Alpha & Gamma neurons

Unidirectional 

segmental 

movement

Epimysium Synergy- 1

                                 Task-1 (Regulation of Muscle activity                                    

                                  and segmental join motion)

         Task-0 (Pre-activation)

     segmental SEP

Action 

destabilization (ASA)
Perimysium

 Primary motorneurons – co-activation gamma-alfa

Alpha & Gamma neurons

Primary motor area

Synergy- 0

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skeletal biomechanics. Although model behavior can 

match human movement and postural data, it omits the 

fascial system, thus its contribution to sensorimotor 

function. 

Synergies 

Degrees of freedom  

How the body organises redundant degrees of freedom 

(DoF) is a crucial question in motor control.33 For a 

system to be redundant, a hierarchical organisation is 

assumed in which each level has more elemental 

variables (i.e. n muscles) than the higher level (i.e. m 

joints) where m<n. The other assumption governing 

redundant systems is that at any level, elemental 

variables are independent from one another. It is not 

surprising that this latter concept sounds reasonable; as 

we introduced before, it is a common thought that 

extracting an element from the system is not going to 

change the function of other elements in the system, 

therefore elements are assumed to be independent. 

However, there are many anatomical evidences that 

disprove this concept; for instance, muscles partially 

insert on the aponeurotic fascia,26,34 some muscles are bi-

articular (crossing two joints) or multi-articular (crossing 

multiple joints).27 Interconnections (at the same level, 

and between levels) creates interdependency hence the 

DoF are already reduced. Notice, only acknowledging 

that muscles insert onto the fascia changes dramatically 

how we see movement organisation. Not only muscles 

produce a pulling force on the bone, but they also stretch 

the fascia creating sequences of movements (discussed 

later). Therefore, DoF are reduced (or better, organized) 

anatomically through the fascial system, thus limiting the 

number of computations needed at any higher level (i.e. 

cerebral cortex). The principle of abundance, introduced 

later,15,35 is different from the problem of motor 

redundancies in the sense that movement is not 

constrained into a single solution, but rather the system 

uses all available DoF at lower levels to facilitate groups 

of solutions equally able to solve the task-at-hand. 

Solutions emerge based on the actual state of the body 

(anatomical constraints), environmental constraints, and 

task constraints.36 The fascial system anatomically 

explains how ‘movement selection’ is achieved at lower 

levels of the chain making the intention possible: the 

focus of the person doing the movement is on the final 

effectors (in voluntary movement initiation) or on control 

parameters (in continuous movements), while the focus 

of the body is on producing the movements needed to 

meet the request. Like the horses pulling the chariot are 

coordinated by the charioteer that in turn, works to meet 

the passenger’s desire.  

Motor Synergy  

Although many definitions of motor synergies may be 

found in literature, motor synergies are best described as 

the hypothetical neural mechanism that ensure task-

specific covariation of elemental variables providing for 

desired stability properties of an important (performance) 

variable. In the act of reaching to an object, performance 

variable is the position of the hand in space, while the 

elemental variables are the arm’s joints angles, and 

torque resulting from muscle fibres contraction. 

Functionally, elemental variables co-vary to stabilize the 

performance variable. This can be also extended to 

posture stabilization. Multiple synergies can arise at the 

same time to solve multiple problems: imagine you are 

walking on the street and you want to check the time. 

Multiple synergies are involved in this rather simple task; 

first, walking is controlled and organized passively by 

feedback loops (continuous movement). Then, the 

intention of looking at the watch activates the 

unconscious anticipatory synergy adjustments,14,37 which 

work to destabilize the synergetic movement of the arm 

swing and to change the muscle fibre threshold to a new 

somatic equilibrium point (see below). As we 

consciously start the arm movement, two different 

synergies (different tasks) for the two arms arise, and this 

has an influence on the  ‘background’ synergy of walking 

that now needs to compensate for the ceased arm swing. 

The function of the fascial system is to automatically help 

the person (self-organisation); the details of the operation 

would distract the walker from his task of keep walking 

at the same speed, in the same direction. Even though 

feedbacks information may reach the nervous system, 

this information is only relevant to the functioning of the 

subservient system, and it should remain private to that 

mechanism.38  

Integration with the fascial system 

Figure 2 represents the hypothesized hierarchical motor 

synergy organisation integrating the fascial system. 

Synergistic levels are organized in a nesting of 

interconnected soft tissues forming physical and 

functional linkages that ensure continuity between 

muscles and connective tissue. Lower level synergies are 

building blocks which higher level synergies are based 

upon. The first synergistic level ‘synergy-0’ concerns 

organisation and coordination of muscle spindles with a 

feedforward (not only feedback) action of converging 

spindles’ tractional forces onto the fascia. The proposed 

premise is that alpha and gamma neurons are always 

active, even though their activation level is under 

threshold, electric potential is keeping tension on the 

muscle fibres, both intra- and extrafusal. This explains 

the basal muscle tone. When we relax a muscle, some 

underlying tension is still perceivable. In the case of 

voluntary (pre-planned) actions, primary motor area 

activates, through primary motor neurons, both alpha and 

gamma motor neurons; this co-activation regards groups 

of motor neurons with the same functional direction. That 

is, all the motor neurons that activates motor units that 

produce movement in the same direction. Alpha pre-

activation is essential to decrease their gain (activation 

threshold; at the same time, because gammas have a 

smaller size, they reach activation threshold before the 

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alphas causing a change in tension on the somatic 

equilibrium point (SEP) through muscle spindles action 

and their insertion on the perimysium (see below). It is 

important to notice that at this level, no apparent 

(detectible) movement is present. Synergy-1 organises 

motor units (belonging to the same segment) that have 

the same direction of contraction, and the segment as a 

whole for movements executed on a single plane (i.e. 

sagittal, frontal, or transverse) – unidirectional segmental 

movements. Synergy-1 has its bases on the physical 

emergency of the SEPs: multiple muscle spindles are 

organized functionally through the SEPs and if the fascia 

is elastic, the intrafusal fibres of the muscle spindles are 

able to shorten, sending efferent signals (Ia and IIa) to 

alpha motor neurons with the same directional meaning. 

The activation of the alpha motor neurons produces the 

contraction of the extrafusal fibres (muscle gross 

contraction). Motor units are therefore pre-activated and 

pre-informed about the position of muscles and joints 

thanks to the perceptive function of the SEPs. In synergy-

1 we talk about segmental SEP as the converging point 

of the resultant force developed by the muscle spindles 

that are functionally linked to the alpha motor neurons 

ipso-directional in a segment. The advantage of having 

segmental SEPs is that the nervous system does not 

receive afferent information from single muscle spindle 

of a muscle, but rather it gathers information from 

specific points – SEPs – that exist thanks to the 30% 

insertion of the extrafusal muscle fibers onto the fascia. 

Moreover, the segmental SEP is physically specular 

(equal direction, opposite verse) to the force developed 

 
 

Fig 3. Schematic of the somatic equilibrium point (SEP) between extrafusal and intrafusal muscle fibres. (A) Fascial 

relation with muscle spindle and the muscle. The spindle is represented as an extensive spring (B) that can be 

compressed by neural activation (C), or by tensional forces (D). Motor synergies characteristics. 

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by the extrafusal fibres on the tendon pulling the bone  

(gross movement). Synergy-2 interests the coordination 

of multiple joints of a limb (or the trunk) anatomically 

and functionally linked through sequential SEP in what 

we call unidirectional global movements. As we will see, 

SEPs lay onto the epimysium but the epimysium is 

linked, through septa, to the aponeurotic fascia. 

Therefore, any traction on a segmental SEP will be 

transferred to SEPs of adjacent segments, and because 

the aponeurotic fascia is seamless, all SEPs ipso-

directional are functionally connected. Thus, motor units 

of adjacent segments are activated (myotatic stretch 

reflex) by passive stretch of muscle spindles connected to 

the SEP of that segment. Synergy-3 organises motor 

units, joints, and spinal reflexes involved in bidirectional 

movements classified as segmental motor schemes (for 

shifting of joints from one plane to another), or global 

motor schemes (for shifting of a limb or the trunk onto 

intermediate planes - diagonals). Synergy-3 deals with 

everyday movements, those that are organized on an 

infinite number of planes. At peripheral level, multiple 

segmental SEPs converge in a somatic equilibrium point 

at a higher synergic level, located where the fascial 

laminae molten: retinacula. This hierarchically higher 

SEP coordinates, through its tension (and a 

proprioceptive feedback) segmental SEPs involved in 

movements on intermediate planes. Higher SEPs are 

organized into diagonals to regulate segmental (or 

global) movement of a limb (or the trunk) in motor 

schemes. Synergy-4 regulates complex movements 

involving multiple joints and multiple planes classified 

as segmental or global multi-directional movements (fine 

or complex motor gests respectively). This last 

synergistic level is governed by SEPs anatomically and 

functionally linked in a spiral way in order to organise 

movements executed onto the three planes.  Synergy-4 

organises fine gests like piano playing and global 

movements such as soccer kick or volley strike. To sum 

up, an ongoing tension on the fascia is present due to 

alpha and gamma under-threshold activity (basal muscle 

tone); following a neural (gamma) stimuli, muscle 

spindles stretch the epimysial fascia of a muscle before 

the contraction of the muscle at its origin and insertion. 

The muscle spindles activated by the same gamma 

impulse (impulse that is assumed to have the same 

directional meaning) generate fascial tractions that will 

 
 

Fig 4.  Hierarchical representation of motor synergies based on the hypothesized integrated neuro-mechanical 

model. AFF = afferent; EFF = efferent; SEP = somatic equilibrium point; N# = group of neurons; IMF l = 

intrafusal muscle fibers length; EMF l = extrafusal muscle fibers length; MN = motor-neuron; 𝜆 = muscles 

length. 

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converge in a point onto the fascia we called somatic 

equilibrium point. In this view, the SEP represents (i) the 

somatic point of equilibrium between the fascial tension 

of the intrafusal and extrafusal muscle fibers; and (ii) the 

point of application of the vectorial resultant of all those 

fascial tractions; in response to which, the muscle belly 

deforms itself in the three planes of space 

simultaneously, changing volume and form of the belly 

before shortening longitudinally. The SEP is at the base 

of three actions: the postural destabilisations, the afferent 

flow of information to the nervous system about the state 

of the muscles, and the coordinative pre-activation of 

muscular contraction sequences specific for a synergy. 

Now that we have established the importance of the 

fascial system in movement organisation, in the next 

section we will describe the structure and function of 

what we hypnotize be the fundamental unit that organises 

movement at the lowest  

The muscle spindle  

Traditionally seen as a feedback regulator system (stretch 

sensitive organ)39 the muscle spindle has gained its 

importance as a feedforward element in recent years .29,40-

43 We hypothesize the muscle spindles are designed to 

regulate muscle activity and movement initiation (for 

voluntary actions), and thanks to their embedment into 

the epimysial fascia they underpin synergies. The role of 

the muscle spindles has been compared with the servo-

control of the road wheels in a car.44 In brief, a sensor 

detects the difference between the position of the steering 

wheel (corresponding to the position of the road wheels 

that the driver wants them – road wheels – to be) and the 

actual position of the road wheels. The system works to 

minimize the difference between the two: actual position 

and desired position of the road wheel. Similarly, we 

hypothesise a double role of the muscle spindle: it 

modulates α activation (through Ia and IIa afferent) while 

also tensioning the epimysial fascia. Thanks to the shared 

connections with the fascia, the tension (tone) of the 

extrafusal fibres (i.e. muscle) is also modulated (Figure 

3). Figure 3A depicts the hypothetical neural and 

physical connections between spindles and muscle fibres. 

Notice that the two points of anchorage for the muscle 

fibres are not both on the tendon but rather one (the SEP) 

is “somewhere” on the belly of the muscle. The position 

of the SEP will be different for movements on different 

planes. Our hypothesis is that spindles have a basal 

tension due to under-threshold activation (Figure 3B) that 

act as compressive spring when their intrafusal fibres are 

neurologically activated through gamma motor neurons 

(Figure 3C); while they are stretched when a physical 

force is applied to them (through the fascia) by extrafusal 

fibres (Figure 3D). Muscle fibres within the muscle 

spindles (intrafusal) are innervated by the gamma (γ) 

motor-neurons while muscle fibres within the muscle 

(extrafusal) are innervated by the alpha (α) motor-

neurons. The concomitant descending innervation for γ 

and α motor-neurons is usually under threshold for alpha 

motor neurons while gamma are activated. We 

hypothesise that this pre-activation, (called anticipatory 

synergy adjustments)14 is necessary to tune in the 

muscles with the task to be performed. The anticipatory 

synergy adjustments activates the muscle spindles (of 

muscles that will be involved in the future movement of 

the end-effector) adjusting their intrafusal fibres length; 

once the voluntary impulse activate the extrafusal fibres 

they will already know the level of activation required 

(feedforward control). The performance variable would 

not change until voluntary activation is started, thus, 

synergy destabilisation is an automatic, involuntary 

action representing a healthy change in basal muscle 

tone.45,46 The equilibrium-point hypothesis,47,48 and more 

recently the referent configuration hypotheses,14,49 

describe closely the function of the anticipatory synergy 

adjustments and the role of the spindles. However, what 

has been described functionally (and analytically), has 

not had anatomical support. The parameters of feedback-

based mechanisms at each level of the hierarchy that 

control lower levels in a feedforward manner have been 

described as having unknown physiology. Although this 

sensory receptors were assumed to have a central role in 

motor synergy (and movement organisation), they were 

located with uncertainty in remote muscles within the 

various segments of the body. We are here presenting an 

anatomical framework explaining the organisation of the 

fascial system that runs in parallel to the neurological 

control of synergies while modulating its output (Figure 

4). The central command defines a referent configuration 

(muscles length) for the body that activates a group of 

neurons (N1) based on subthreshold depolarisation and 

minimal excitatory afferent input (AFF), thus leading to 

N1 response (EFF).50 At each hierarchical level, a 

reference configuration exists, hence each level 

represents a feedback system controlled in a feedforward 

way. We argue that while the command goes to the end 

effector, the synergetic movements are controlled from 

the lowest level up by transfer of tension through the 

fascial system: the tension at the SEPs defines the 

somatic equilibrium point for muscles of the end effector; 

in turn, the tension on the segmental SEP defines the 

somatic equilibrium point for the segmental joints 

interested by the movement; the tension on the sequential 

SEP defines somatic equilibrium point for the sequential 

joints (limb motion on one special plane); tension on the 

diagonal SEP defines the somatic equilibrium point for 

limbs in diagonal movements (motion in two planes); and 

finally, tension on spiral SEP defines the somatic 

equilibrium point for limbs in spiral movements (limbs 

motion on multiple planes of the space). These 

anatomical (fascial) sensors act as bridges between 

different synergistic levels; they allow transfer of tension 

from the lowest level to the highest, ensuring proper 

muscle activation hence proper movement. Their 

organisation is still redundant (# of SEPs< # of segmental 

SEPs < # of sequential SEPs) and automatic (self-

organisation), but they act in an opposite direction than 

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the neural control. It is important to highlight that not all 

synergic levels will be active for any given movement. In 

fact, activation of multiple level synergies happens in 

response to the complexity of the movement and on the 

number of body segments involved in the action. Also, 

the type of movement will define synergies: i.e. for ‘rapid 

pre-planned learned movement’ the anticipatory synergy 

adjustments and its preparatory effects will be present; 

however, for rapid but ‘unintended naive movements’ 

activation of alpha motor neurons will overwrite the 

gamma pathway, hence, movement will be less 

controlled and more prone to injuries as the anatomical 

structures linked with extrafusal fibres are not able to 

react as quickly to those muscle contractions. On the 

other hand, ‘cyclic movements’ rely heavily on fascial 

control and organisation of movements so that we do not 

need to worry about it and more important we can 

accomplish multiple tasks together. 

Research Implications 

Muscle modelling has been introduced to understand 

muscle contribution to movement: by knowing body’s 

segments length, their kinematics (segments’ 

configuration) and kinetics (force produced on the 

ground), it is possible to estimate muscle groups moment 

of force (i.e. extensor moment); from here, based on 

anatomical knowledge of origin and insertion of muscles, 

it is possible to estimate their contribution.51 However, if 

we consider the fascia creates anatomical links between 

muscles and groups of muscles,34 and if we recognise that 

the insertion and origin of the,52 the foundation of 

modelling shakes. Away from suggesting modelling is 

not worth pursuit, we echo the concerns recently brought 

about on the accuracy of modelling estimation.53 hence 

clinical inferences based on modelling may be pushing 

the boundaries of how much we can estimate from a 

‘simple’ model and what clinical relevance it has. 

Robotics may greatly improve by introducing a pseudo-

fascial system into development of assistive devices: for 

instance, for active and passive exoskeletons, the 

distribution of forces along the body segments has been 

always the ultimate challenge. Feedforward control 

based on feedback information at a local level could be 

improved by introducing interlinks between levels so that 

all elements act in harmony with the all system. The 

fascial system presupposes a spiral distribution of the 

somatic equilibrium points on the body, thus forces are 

not distributing linearly through the body segments and 

through the anatomical structures. Perhaps by mimicking 

fascial organisation robotic models may be more 

successful in assisting people in need. 

Clinical Implications 

In case of traumatic events, structural overloading, 

metabolic disorders, or clinical surgeries the fascial 

system may lose its functional properties hence affecting 

the control of movement. Rehabilitative intervention may 

integrate their focus on muscle health with connective 

tissue health. Working on the anatomical receptors 

(somatic equilibrium points) will re-establish a correct 

activation of the subsequent (hierarchically lower) 

components. For instance, for sport skills involving spiral 

movement would require an intervention on SEP laying 

on the movement sequence interested. Not only may 

those point be used for treatment but also for 

evaluation.54 In fact, if these point represent somatic 

equilibrium points, they reflect the balance between 

muscle force and fascial tension: in a healthy body the 

fascial system is free to move and transmit tension along 

the path, however, in case of rigidity of the fascial 

structures, elements will not be in balance resulting in 

pain and possibly leading to injuries.55 

Hypothesis testing 

Our hypothesis can be tested using either a computational 

model or in-vivo measurements. The former, by 

implementing the fascial system (with all its layers), will 

extend the alpha-gamma model.32,56 Such model will 

demonstrate the coordinative role of the fascial system 

over posture maintenance and movement coordination. 

However, the approach presumes knowledge of the 

elastic properties of each layer, and of the link type 

between different layers. The latter comprises quantum 

dot based flexible strain sensors,57 to directly measure the 

stretch of the fascia caused by a muscle contraction. 

Photo-luminescence changes when strain is applied. This 

minimally-invasive technique may be applied over the 

flexible strain sensors made of polymers firmly attached 

to the muscle fascia. If the SEP exists, and therefore our 

hypothesis is valid, we may be able to measure points of 

high stress on the fascia where the forces are converging 

during controlled movements. 

Conclusion 

Many researchers and scientists have described and 

quantified movement organisation from a mathematical 

and physiological point of view. With this essay we 

corroborate the ideas presented in the equilibrium point 

hypothesis and reference configuration hypothesis, 

adding a more in-depth anatomical explanation for 

movement organisation. Implementing the fascial system 

in those theories gives a more complete view on how 

human body organizes movement.58 We elucidated the 

communality between these theories and suggested 

possible research and clinical applications of the 

concepts herein discussed. We may be still far away from 

fully understanding how human body works, but 

including the connective tissue in motor control may 

enlighten some of the anachronistic concepts that have 

lead the scene of motor control for many years. 

List of acronyms 

AFF  - minimal excitatory afferent input  

DoF  - degrees of freedom  

EFF - N1 response 

SEP  - Somatic Equilibrium Point   

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Fascia and motor control 

Eur J Transl Myol 29 (3): 185-194, 2019 

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Authors contributions 

Authors equally contributed to the conceptualization, 

drafting and writing of the manuscript. 

Acknowledgments 

We thanks Dr Simon Taylor for comments that greatly 

improved the manuscript. Funding This work was 

supported by the Fascial Manipulation Institute, via 

Cavalieri di Vittorio Veneto, 19, 35129 Padova (Italy) 

Conflict of Interest 

The authors declare no conflict of interest. 

Ethical Publication Statement 

We confirm that we have read the Journal’s position on 

issues involved in ethical publication and affirm that this 

report is consistent with those guidelines. 

Corresponding Author 

Alessandro Garofolini. Institute for Health and Sport 

(IHES), Victoria University, Melbourne, Australia.   

ORCID: 0000-0002-1789-2362 Phone: 0401613287 

Email: alessandro.garofolini1@live.vu.edu.au 

E-mail of co-author 

Daris Svanera: sva8@hotmail.it 

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Submission: May 29, 2019 

Revision received: August 01, 2019 

Acceptance: August 02, 2019 

 

 

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