Note: Descriptions are shown in the official language in which they were submitted.
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HEADSTAND ASSISTING IMPLEMENT
FIELD OF THF_ 1NV~NTI~N
The presenfi invenfiion relates to the general, field of implements for
performing physical
exercise and is particularly concerned with a headsfiand assisting implement.
BACKGROUND 4F THE INVENTION
The word "yoga" is dorived from the Sanskrit "yeung", meaning to join, In
Hindu
philosophy, yoga is used to atkain spiritual insight and harmony. In Western
countries,
the terra yoga is often used interchangeably with "hatha yoga".
The practice of "hatha yoga" involves performing various physical postures and
relaxation exercises. The yogis physical exercises are called Asanas, a term
which
means steady pause. This is because Yoga Asanas are typically meant to be held
for
some time. Yoga Asanas typically focus on fihe health of the spine, its
strength and
flexibility.
Although there are probat~ly millions of Asanas, twelve selected pauses are
considered
as basic postures. Known as the "king of Asanas" because of its many benefits,
the
headstand is the first of the twelve basic Asanas. The headstand consists in
balancing
on the crown of the head als4 referred to as the Sahasrara chakra-
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The headstand is considered by many to be a panacea for countless human ills,
Benefits of performing the headstand includesv a) reversal of venous flow,
thus flushing
out areas of stagnant or collected blood; b) reversal of the filow of oerebro-
spinal fluid,
resulting in formation of new cerebro-spinal fluid in the region of the
intracerebral
ventricles; c) activation of the carotid sinus barorereceptc~rs, resulting in
increased
discharge from the parasympathetic nervous system, thus lowering heart rate
and blood
pressure; d) strengthening of the paraverkebral musculature; e} improvement of
balance as a result of the establishment of new neural circuitry by the new
demand fur
balance placed on the cerebellum and vestibular apparatus; f} improvement in
concentration; g) improvement in endurance; and h) improvement in relaxation
and
general weU being.
Although net necessarily considered an advanced Asana, the headstand
nevertheless
requires some level of experience and may be potentially hazardous. Indeed,
when
performing a headstand, the cervical spine, in particular, may be subjected to
important
stresses that may potentially lead to serious injury.
Some believe that the headstand should net be performed by individuals having
cervical
spc~ndylosis, blocked arteries, astea-arthritis of the neck or shoulders,
backache,
premenstrual stress or high blood pressure. Furthermore, it is typically
recommended
to get help from a yoga practitioner to perform the headstand in a correct and
safe
manner.
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There exists several methods for performing a yoga headstand. Typically, the
sequence is initiated by coming onto the elbows and knees about 8 inches away
from a
wall. The hands are then placed to the outside of the triceps muscles to
establish a
beginning arm position. The elbows are then released and the fingers
interlocked
creating a "V" stance with the forearms. The crown of the head is then rested
on the
floor.
The toes are then tucked under and, white inhaling, the hips are lifted and
the legs
straightened. The neck must be maintained in proper alignment throughout the
procedure.
Once this initial positian has been established, one foot is placed in front
of the other,
preferably the stronger leg forward. It is typically recommended that most of
the weight
should rest on the elbows and not on the crown of the head. However, this may
actually
train the bad habit of having the mechanical axis of the spine anterior to the
anatomic
axis.
The abdominal muscles and the pelvic floor muscles are contracted and, slowly,
one leg
at a time, the individual floats the feet up resting the legs on the wall.
When headstand
is taught in this way, the weight does not rest on the crown of the head, but
rather rests
on the elbows. It is recommended to keep the legs together and the toes
spread.
When practiced as described in the foregoing it is only when the neck is very
strong and
the individual has been practicing for many years that he or she can then
place the full
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weight of tile body on the head. As the headstand posture is practiced, from
the starting
position the abdominal muscles may be engaged first and both legs then slowly
floated
up together until in the inverfied headstand position. Eventually, as the
posture is
established, the individual can move away from the wall and attempt it in a
free~stand
position. Typically, the posture is held for 5 to 10 deep breaths. Many other
sequences
may be used to achieve a proper headstand.
Typically, most people recommend that most of the weight be distributed onto
the hands
andlor forearms in order to "protect" the spine. However, it is believed that
by
maintaining most of the weight on the forearms andlor hands, the spine may in
fact
become more wlnerable since the mechanical axis of the body is shifted (onward
of the
cervical spine. By shifting the mechanical axis away from the anatomic axis of
the
vertebral column, the spine and its surrounding musculature become at risk for
both
acute arid chronic injury. Furthermore, the advantage of aligning the body
weight with
the trabeculae of the vertebral bodies, which combined with the intervertebral
discs can
withstand very high compressive farces, is lost if the mechanical and anatomic
axis are
not aligned.
When the headstand is performed with the mechanical axis of the spine
substantially
aligned with the anatomic axis, the weight of the body is concentrated in a
small area of
a part of the cranium, commonly referred to as the crown, where it is in
contact with the
floor. The sustentation polygon or surface within which the centre of gravity
of the body
must project in order to maintain the body in the inverted position without
falling over is
relatively small. Furkhermore, the surface of the cranium in contact with the
ground has
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a somewhat convex configuration which further reduces the overall stability of
the
position.
Sway or imbalance is magnified when one attempts to maintain the mechanical
axis and
the anatomic axis concentrated in such a small area, Furthermore, in the
inverted and
erect position, the body becomes a long lever arm such that movements caused
by
relatively small forces became magnified. Such small forces can reach
signifiicant levels
to a paint that imbalance is created by the sway.
This sway must be countered by muscular forces in order to maintain the body
in the
headstand position. These forces, in turn, can reach relatively high levels
and are
transmitted in the form compensatory flexion, extension and rotary oration at
the
vertebral bodies. These orations and forces can result in disc bulging or
herniation.
Hence, it would be desirable to provide a headstand assisting implement
allowing an
intended user to assume the inverked and erect position associated with
conventional
headstands wherein the mechanical and anatomic axes are in a substantially co-
linear
relationship relative to each other but without the hereinabove mentioned
disadvantages
associated with such a position_ !n other words, it would be desirable to
provide a
headstand assisting implement that could allow an intended user to perform a
headstand wherein involvement of the forearms is minimized and wherein the
need for
providing compensatory movements to maintain balance is also minimized.
SUMMARY OF THE INVENTION
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It is a general object of the present invention to provide a headstand
assisting
implement adapted to assist an intended user in ergonomically performing a
headstand.
In accordance with the present invention, there is provided a headstand
assisting
implement for assisting an intended user while the intended user performs a
headstand,
the intended user having a head including a cranium, the headstand assisting
implement comprising: an implement body, the implement body defining a ground
contacting surface for resting on a ground surfiace and a substantially
opposed cranium
contacting surface for contacting the cranium of the intended user; the
cranium
contacting surface being provided with a cranium receiving concavity, the
cranium
receiving concavity being configured and sized for substantially fittingly
receiving a
predetermined portion of the cranium of the intended user so as to
ergonomically
support the cranium of the intended user when the intended user performs the
headsfiand.
Conveniently, the cranium receiving concavity has a substantially ovoid
configuration
when seen from a flop view, the ovoid configuration of the cranium receiving
concavity
defining a concavity long axis extending substantially longitudinally across
the cranium
receiving concavity and a substantially perpendicular concavity short axis
extending
transversally across the cranium receiving concavity, the concavity long and
short axes
being sized so fihat the outline of the cranium receiving concavity
corresponds
substantially to the outline of the predetermined portion of the cranium of
the intended
user.
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lareferably, the cranium receiving concavity defines a concavity main section
and a
concavity auxiliary section, the Concavity main section kreing located
substantially
centrally relative to the cranium receiving concavity; the concavity auxiliary
section
being located peripherally relative to the concavity main section, the radius
of curvature
of the concavity auxiliary section being greater then the radius of curvature
of the
concavity main section;
In at least one embodiment of the invention, the Concavity main section is
hollow. In
another embodiment of the invention, at least a portion of the concavity main
section
and the concavity auxiliary section are made out of diffe~nt materials:
Preferably, the implement body is made nut of an integral piece of
substantially
resiliently defarmable body material.
Advantages of the present invention include that the proposed implement allows
an
intended user to perform a headstand with reduced risks of injury. The
proposed
implement is also intended to provide a greater sense of comforfi, security,
stability and
capability to an intended user practicing headstands.
1n turn, the improved comfort, security, stability and capability enable the
body of an
intended user to maintain headstands for a longer period of time. It also
enables the
intended user to place the body in a variety of headstand positions.
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The proposed implement is designed so as to allow the body of the intended
user to
maintain its mechanical axis substantially in line with the anatomic axis
during
performance of the headstand.
Also, the proposed implement is designed so as to act as an interface between
the
crown of the head of the intended user and the ground surface and to provide
an
enlarged contact surFace with the ground surtace.
Still furthermore, the proposed implement is designed so as to provide self
alignment
features adapted to reduce the need for the intended user to exert muscular
tension in
an attempt to maintain balance. In other words, the proposed implement is
designed so
as to improve the stability of the intended user when the latter is in the
headstand
position.
Also, the proposed implement is designed so as to be usable by a wide range of
users
having a relatively wide range of anthropometric values in terms of head size
and
conlrguration.
Yet, still furkhermore, the proposed implement is designed so as to be
manufacturable
~rsing c4nventional forms of manufacturing 2nd conventional materials so as to
provide
an implement that will economioally feasible, long-lasting and relatively
trouble-free in
operation.
SRIFF I~ESGRIPTION OF THE DRAWINGS
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Various embodiments of the present invention will now be disclosed, by way of
example, in reference to the following drawings in which:
Figure 1, in a perspective view, illustrates a headstand assisting implement
in
accordance with an embodiment of the present invention;
Figure 2, in a top view, illustrates the headstand assisting implement shown
in Fig. 1;
Figure 3, in a parti2~l perspective view With sections taken out, illustrates
some of the
features of the headstand assisting implement shown in Figs. 1 and 2;
Figure a, in a longitudinal cross-sectional view taken along arrows IV-IV of
Fig. 2,
illustrates some of the features of the headstand assisting implement shown in
Figs. 1
through 3;
Figure 5, in a longitudinal cross-sectional view similar to that of Fig. 4,
illustrates a
headstand assisting implement in accordance with a second embodiment of the
present
invention;
Figure 6, in a longitudinal cross-sectional view similar to that of Figs. ~
and 5, illustrates
a headstand assisting implement in accordance with a third embodiment of the
present
invention;
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Figure '~, in a transversal cross-sectional view, illustrates a headstand
assisting
implement in accordance with an embodiment of the present invention, the
headsfiand
assisting implement being shown used by an intended user in the headstand
position,
the intended user being shown in phantom lines and part of the vertebral
column Qf the
intended user being shown in full lines;
Figure $, in a transversal cross-sectional view, illustrates a headstand
assisting
implement in accordance with an embodiment of the present invention, the
headstand
assisting implement being shown with the head of an intended user resting
thereon, the
head being shown in phantom lines and in an angular offset relationship
relative to a
verkical axis, part of the cervical spine of the intended user being shown in
full fines.
DETAILED DESCRIPT10N
Referring to I=ig. 7, there is shown, in a transversal cross-sectional view, a
headstand
assisting implement in accordance with an embodiment of the present invention
generally indicated by the reference numeral 10. The implement 90 is shown
being
used by an intended user 12 performing a headstand.
The intended user 12 has a head ~~4 supported by a neck 16 extending from a
torso 18
The intended user 1~ also has a pair of arms including forearms 20 and a pair
of legs
22 extending from the torso 1 S.
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In Fig. 7, the intended user 12 is shown perForming a typical yogic posture or
Asana
wherein the legs 22 are crossed and wherein the back of the head 14 is placed
in the
hollow ofi the palm (not shown). It should, however, be understood that the
implement
1 Q could be used fior pertorming other types of headstands without departing
from the
scope ofi the present invention. Furthermore, although the implement 10 was
primarily
designed for use in practicing yoga or the like, it should be understood that
the
implement 10 could be used in other contexts and for practicing other types of
activities
such as gymnastics, general physical conditioning or the like without
departing from the
scope of the present invention.
The head 14 of the intended user 12 includes a cranium. As is well known in
the ark,
when seen from the top, the human cranium typically has a 5ubst2~ntially ovoid
or egg-
shaped outline or confiiguration. When seen from the front or the rear, the
top portion or
crown 24 of the hum2~n cranium typically has a substantially rounded and
convex
configuration or outline. Although Figs. ~' and 8 illustrate a cranium having
a crown
portion 24 with speck anthropometric parameters, It should be understood that
the
implement 10 is intended to be used by individuals having a variety of cranium
anthropometric parameters without departing from the scope of the present
invention.
Figures 7 and 8 also schematically illustrate part of the vertebral column 26
of the
intended user 12. As is well known in the art, the vertebral column includes
vertebrae
28 and intetvertebral discs 30 positioned therebetween.
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The headstand assisting implement 10 includes an implement body 32. The
implement
body 32 defines a crown contacting surface 34 for resting on a ground surface
3B. The
implement body 32 also defiines a substantially opposed cranium contacting
surface 38
for contacting the cranium of the intended user 12.
As illustrated more specifiically in Figs. 4, 5 and 6, the cranium contacting
surtace 3~ is
provided with a cranium contacting concavity 40. The cranium receiving
concavity 40 is
configured and sized far substantially fittingly receiving a predetermined
portion at the
cranium of the intended user 12 so as to ergonomically support the cranium of
the
intended user 12 when the latter performs a headstand.
As illustrated more specifically in Fig. 2, the cranium receiving concavity 40
has a
substantially ovoid configuration when seen from a top view. The ovoid
configuration of
the cranium receiving concavity 40 defines a concavity long axis 42 extending
substantially longitudinally across the cranium receiving conrevity ~40. The
ovoid
configuration of the cranium receiving concavity 40 also defines a
substantially
perpendicular concavity short axis 44 extending transversely across the
cranium
receiving concavity 40. The concavity long and short axes 42, 44 are sized so
that the
outline of the cranium receiving concavity 40 corresponds substantially to the
outline of
the predetermined portion of the cranium of the intended user 12.
Typically, the cr2~nium receiving concavity 40 is configured and sized fnr
substantially
fittingly receiving the so-called crown portion 24 of the cranium of the
intended user 12.
Preferably, the crown portion 24 intended to contact the cranium receiving
concavity 40
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is defined as extending between the two parietal bones and the posterior
portion of the
frontal bone, the center of the cranium receiving portion being the native
fontanelle.
The cranium receiving concavity 4fl is configured and sized far substantially
fittingly
accommodating the crown portion of an intended user having anthropometric
parameters located between that of the 5~' and 95a' percentile of human
craniums.
Typically, the concavity long axis 42 has a value of 2~pproximately between
12.5
centiimetres and 14 centimetres and the concavity short axis 44 has a value of
approximately between 10 centimetres and 11.2 centimetres-
As illustrated more specifically in Figs. 4 through 6, the cranium receiving
concavity A0
typically has a substantially flattened parabolic configuration when seen in a
longitudinal
cross-suction taken about the anal long axis 42. Typically, the profile of the
surface of
the cranium receiving concavity along the concavity short axis 44 also has a
substantially parabolic canfwguration.
As illustrated more specifically in Figs. 1 and 2, the cranium receiving
concavity ~.D
defines a concavity main section 46 and a concavity auxiliary section 4$. The
concavity
main section 46 is typically located substantially centrally relative t0 the
Cranium
receiving concavity 40 while the concavity auxiliary section 48 is typically
located
peripherally relative to the concavity main section 46.
As illustrated more specifically in Figs. 4 through B, the radius of curvature
of the
concavity auxiliary secfiion 48 is greater than the radius of curvature of the
Concavity
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main section 4S. The concavity main section 46 defines a main section radius
of
curvature 50 while the concavity of the auxiliary section 48 defines an
auxiliary section
radius of curvature 52. Typically, the main section radius of curvature has a
value of
approximately between 20 cm and 22 cm while the concavity of the auxiliary
section
radius of curvature 52 has a value of approximately between 36 cm and 59 cm.
As seen mnre specifically in Fig. 2, the concavity main section 46 also has a
substantially avoid configuration. The ovoid configuration of the concavity
main section
46 defines a main section long axis extending substantially longitudinally
across the
concavity main section 46 and a substantially perpendicular main section short
axis
extending substantially transversely across the concavity main section 46.
Typically,
the main section long axis has a value of approximately between 6.25
centimetres and
7 centimetres while the main section short axis has a value of approximately
between 5
centimetres and 5.6 centimetres.
The cranium receiving cavity 40 defines a Concavity peripheral edge 54. As
illustrated
more specifically in Fig. 4, the level difference between the concavity
peripheral edge 54
and the nadir of the cranium receiving concavity 40 defines a concavity depth
56.
Typically, the concavity depth 66 has a value between 1.6 centimetres and 1.8
centimetres.
The distance between the nadir of the cranium receiving concavity 40 and the
ground
contacting surFaee 34 defines a body minimal thickness ~8. Typically, the body
minimal
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thickness 58 has a value of approximately between .635 centimetres and 1.0
centimetre.
Typically, the concavity peripheral edge 54 has a substantially rounded
configuration or
contour. The concavity peripheral edge 54 hence defines a corresponding
peripheral
edge radius of cunrafiure 60. The peripheral edge radius of curvature 60
typically has a
value of approximately between .3 centimetres and .5 centimetres.
The implement body 32 includes a body peripheral surface 62 extending between
the
concavity peripheral edge 54 and the ground cantaeting surface 34. The body
peripheral surface 62 tapers generally inwardly in a direction leading from
the ground
contacting sulfate 34 to the concavity peripheral edge 54.
The body peripheral surface 62 extends at a peripherah.to~ground contacting
surface
angle 64 relative to said ground contacting Surface 34. Typically, the
peripheral.-to-
ground contacting surface angle 64 has a value of approximately between 65
degrees
and 94 degrees.
The implement body 32 is preferably made out of an integral piece of a
substantially
re$iliently deformabte body material. Typically the body material is a
polymeric or
elastomeric resin. Typically, the body material is a Urethane polymer sold
under the
Trademark Gel or Evergreen #90..A (non toxic) or other substantially similar
suitable
material. Typically, the body material provides substantially the following
characteristics:
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a viscosity of approximately $00 PCS, an elongation of approximately 1.000%, a
tensile
strength of approximately: 200 PSI and a tear of approximately PLI 25 PI
As illustrated more speci~caliy in digs. 3 through 6, at least the cranium
t'eceiving
concavity 40 and typically both the cranium receiving concavity ~0 and the
body
peripheral surfaces 62 are coated with a coating material having a coating
material
friction co-efficient equal to or tower then that of Lycra (a trademark).
Typically, the
coating material is a coating layer or film 66 of Lycra or similar material
adhesively or
otherwise secured to the implement body 3z.
in use, as illustrated in Figs. 7 and 8, the implement 10 is adapted to
ergonomically
support the crown portion 2~. of the cranium of the intended user 12 when the
latter
performs a headstand. The configuration and size of the cranium receiving
concavity
40 allows the latter to act as a socket for substantially fittingly receiving
the crown
portion of the cranium.
The combination of the dimensional characteristics of the implement ?0 and of
the type
of material chosen for forming the implemenfi body 32 allows the implement 10
to
functionally accommodate a wide range of crown Section configurations and
sizes.
Indeed, the selected dimensional Characteristics and degree of resiliency of
the material
synergistically combine to provide a tight fit to intended users having a wide
range of
anthropometric characteristics.
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The concavity main section 46 is configured and sized for contacting the
portion of the
cranium of the intended user 12 that would contact the ground surface 36 if
the
implement 10 were not used and if the body of the intended user 12 was
properly
balanced along a substantially vertical axis 68. The concavity main section 4~
is
intended to provide that portion of the crown section of the intended user 12
with a
somewhat more ductile or soft contacting surface than that of the ground
surface 3B.
The concavity 2~uxiliary section ~.8 is adapted to provide a greater contact
surface with
the cranium of the intended user 1~ them that which would have bean in contact
with the
ground surtace 36 should the implement 10 had not be used and the intended
user 12
has nevertheless been in a balanced vertical position. Hence, the contact
surface with
the cranium is increased by the concavity auxiliary Section 48.
T'he contact surface with the ground surface 36 is also increased by the
implement 10
since the body peripheral surface 62 tapers generally inwardly in a direction
leading
from the ground contacting surface 34 towards the concavity peripheral edge
5~4_ The
body peripheral surface 62 is configured and sized for increasing the contact
area of the
cranium of the intended user 12 transmitted by the implement 10 td the ground
surface
36 without interfering with surrounding structures such as the forearms 20 of
the
intended user 12. Indeed, as shown in Fig. 7, the implement 10 is configured
and sized
so as to leave a clearance between the implement 10 and the forearms 20 of the
intended user when the latter u$es the forearms 20 for additional support.
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The radius ofi curvature of the concavity auxiliary section 48 allows the
latter to be
angled relative to the ground surface 3B so as to provide a reaction force
against the
weight of the intended user 12, the reaction force having a horizontally
extending vector
segment so as td further help in stabilizing the intended user 1Z in the
proper position.
Furthermore, as illustrated mute speciFcally In Fig. S, the resilienffy
deformable nature
of the body material from which the implement body 32 is made is such that the
implement body 32 is adapted tc~ controllably deform upon the axis 70 of the
vertebral
column 26 deviating from the vertical axis 68. This controlled deformation of
the
implement body 32 protects the spine and, mare specifically, the
intervertebral dISCS by
mitigating and taking up the bulging that would normally occur during
compensatory
adjustment as a result of body sway during the headstand.
Furthermore, the resilient nature of the body material from which the
implement body 32
is made is such that, upon deformation, the implement body 32 will tend to
resiliently
spring back to its original configuration hence creating self aligning biasing
forces that
will tend to bias the vertebra) column axis 70 towards the ve~jcal axis 68 as
indicated by
arrow 72 in Fig. $. These inherent self aligning forces, in turn reduce the
need for
compensatory movement andlor forces emanating from the user body that could
potentially lead to injury.
In order to further increase the comfort associated with the use of the
implement 10, the
resilient nature of the body material from wniCh t~t~ implement body 32 is
made
synergistically combines with the dimensional characteristics of the Concavity
peripheral
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edge 54 taking into consideration other parameters from both the intended user
12 and
the implement 10.
The body minimal thickness 58 is aiso designed taking into consideration the
nature of
the body material from which the implement body 32 is made so as to prevent
the head
contacting surtace 3~ from contacting the ground surface 36 andlor prevent the
implement body 32 adjacent the head contacting surface 38 from being
compressed to
the point of having a modulus of elasticity having a value over a
predetermined
threshold that would make usa of the implement 10 uncomfortable.
Referring more specifically to Fig. 5, there is shown a headstand assisting
implement in
accordance with an alternative embodiment of the invention generally indicated
by the
reference numeral 10'. The implement 10' is substantially similar to the
implement 10
and, hence, similar reference numerals will be used to denote similar
components.
One of the main differences between the implements 10 and 10' resides in that
at least
part of the concavity main section d.6 of the implement 10' is hollow. In
other words, a
central aperture 74 extends through the implement body 32 in the region o'f
the
cvncavityr main section 3B.
Referring now more specifically to Fig. 6, there is shown a headstand
assisting
implement in accordance with a third embodiment of the present invention,
generally
indicated by the reference numeral 10". The implement 10" is substantially
similar to
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the implements 10 and 10' and, hence, similar refierence numerals will be used
to
denote similar components.
One of the main differences betvueen the implement 10" and the implements 10
and 10'
resides in that at least part of the concavity main section 46 and the
concavity auxiliary
section 9~8 are made out of different materials. Fig. 6 illustrates a
situation wherein an
insert 7B made out of a different material is used. Preferably, at least part
of the
concavity main section 46 is made out of a material having a Power modulus
elasticity
than that from which the concavity auxiliary section 48 is made.
Typically, at least the concavity main section is made out of a material
having a
modulus elasticity having a value of approximately between 100 and 400 kPA and
at
least part of the concavity auxiliary section 48 is made out of a material
having a
madulus elasticifiy having a value of approximately between 10 and 40 kpA.
Typically, the modules elasticity of the concavity main and auxiliary sections
46, 48 is
substantially similar to or Iawer than the cnrrespanding rnodulus elasticity
of the nucleus
pulposus and annulus fibroses of a physiologic inteivertebral disc.
