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ance on the tensional side of the spectrum. The flexible
core is held aloft by a balance of the cords attached to its
'processes'. With the cords in place, pulling on them can
put the mast anywhere within the hemisphere defined
by its radius. Cut the cords, and the flexible core would
fall to the ground, unable to support anything. This
arrangement parallels the iliocostalis muscles, seen on
the outer edge of the erectors in Figure 1.62.
While we are convinced that the body's overall archi-
tecture will ultimately be fully described by tensegrity
mathematics, perhaps the safer statement at this point
is that it potentially can be so employed, but frequently
and sadly is used less efficiently, as described above.
While this is a subject for further research and discus-
sion, what is clear is that the body's tensile fascial
network is continuous and retracts against the bones,
which push out against the netting. What is clear is that
a body distributes strain - especially sustained long-
term strain - within itself in an attempt to equalize
forces on the tissues. It is clinically clear that release in
one part of the body can produce changes at some dis-
tance from the intervention, though the mechanism is
not always evident. This all points toward tensegrity as
an idea at least worthy of consideration, if not the
primary geometry for constructing a human. The models
of inventor Tom Flemons ( www.intensiondesigns.com a nd
Figs 1.49B, 1.52 and 1.57-1.59) are wonderfully evoca-
tive. These early 'force diagrams' of human standing
approach, but do not yet replicate in their resilience and
behavior, a human architectural model. They are bril-
liantly suspended in homeostasis, but are of course not
self-motivating (tropic) as with a biological creature.
to lie in the direction of the tensional part of the applied
stress, resulting in a linear stiffening of the material
(though distributed in a non-linear manner).
This is certainly reminiscent of the reaction of the
fibrous system to mechanical stresses that we described
in the beginning of this chapter in response to piezo-
electric charges, as well as simple pull - take a wad of
loose cotton wool and gently pull on the ends to see the
multidirectional fibers suddenly line up with your
fingers in a similar way until the stretching comes to a
sudden stop as the fibers line up and bind. Our fibrous
body reacts similarly when confronted with extra strain,
just like a tensegrity structure or a Chinese finger puzzle
(Fig. 1.64).
In other words, tensegrity structures show resiliency,
getting more stiff and rigid (hypertonic) the more they
are loaded. If a tensegrity structure is loaded before-
hand, especially by tightening the tension members
('pre-stress'), the structure is able to bear more of a load
without deforming. Being adjustable in terms of 'pre-
stress' allows the biological tensegrity-based structure
to quickly and easily stiffen in order to take greater
loads of stress or impact without deforming, and just as
quickly unload the stress so that the structure as a whole
is far more mobile and responsive to smaller loads.
We have described two ways in which the myofascial
system can remodel in response to stress or the anticipa-
tion of stress: (1) the obvious one - muscle tissue can
contract very quickly at the nervous system's whim
within the fascial webbing to pre-stress an area or line
of fascia, and (2) long-term stresses can be accommo-
dated by the remodeling of the ECM around piezo-
electric charge patterns, adding matrix where more is
demanded. Recently a third way to pre-stress the fascial
sheets has emerged (the research was begun some time
ago, but the story has only recently made it to bodywork
and osteopathic circles), so we include a brief report on
this new class of fascial response - the active contraction
of a certain class of fibroblasts on the ECM itself.
The reader may well ask: If fascial cells display active
contractility within the matrix, why has it taken us this
long into the chapter to say so? All our previous discus-
sion has centered on the passive response of the cells
and the matrix itself to outside forces coming through
the matrix. Might not an element this important have
come up earlier in the discussion of the fascial net?
The reason for our placement of this new research is
that the unique role of the myofibroblasts provides a
perfect transition between the tissue-and-bone world of
macrotensegrity to the cytoskeletal world of micro-
Pre-stress
Once we take these models into motion and differing
load situations, we need more adjustability. Loose
tensegrity structures are 'viscous' - they exhibit easy
deformation and fluid shape change. Tighten the tensile
membranes or strings - especially if this is done evenly
across the board - and the structure becomes increas-
ingly resilient, approaching rigid, columnar-like resis-
tance until they reach their breaking point.
As Ingber 10 3 puts it: 'An increase in tension of one of
the members results in increased tension in members
throughout the structure, even ones on the opposite
side.' In fact, even more specifically, all the intercon-
nected structural elements of a tensegrity model rear-
range themselves in response to a local stress. And as
the applied stress increases, more of the members come
Fig. 1.64 By 'pre-stressing' a tensegrity
structure, that is, putting a particular strain
on it beforehand, we notice that (1) many
of the members, both compressional and
tensional, tend to align along the lines of
the strain, and (2) the structure gets 'firmer'
- prepared to handle more loading without
changing shape as much. (Photo courtesy
of Donald Ingber.)
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