Patent Publication Number: US-2002007569-A1

Title: Work insoles

Description:
BACKGROUND OF THE INVENTION  
       [0001] The present invention relates generally to insoles for footwear, and more particularly, to improved insoles particularly adapted for working people that spend much time on their feet.  
       [0002] There are many working people, such as construction workers, cashiers, etc., that spend most of their working time in a standing position. Further, much of this standing occurs on hard floors, such as concrete floors or the like. This has the tendency to cause lower back pain and lower extremity pain.  
       [0003] As a result of this pain, working people tend to alter their posture and gait, in an attempt to alleviate this pain.  
       SUMMARY OF THE INVENTION  
       [0004] Accordingly, it is an object of the present invention to provide an insole that overcomes the problems with the aforementioned prior art.  
       [0005] It is another object of the present invention to provide an insole that relieves lower back pain and lower extremity pain.  
       [0006] It is still another object of the present invention to provide an insole which works faster and better than conventional insoles in relieving lower back pain and lower extremity pain.  
       [0007] It is yet another object of the present invention to provide an insole that provides cushioning and shock absorption at every point along the foot stride.  
       [0008] It is a further object of the present invention to provide an insole that provides additional shock absorption where needed at high force areas along the foot stride.  
       [0009] It is a still further object of the present invention to provide an insole that provides a biomechanical effect in rolling through the gait, to enhance the stance and correct gait of the foot.  
       [0010] In accordance with an aspect of the present invention, a full length insole for use with footwear, comprises a first layer including a forefoot portion extending at least to metatarsals of a foot, a heel portion, a mid portion connecting together the forefoot portion and the heel portion, an upper surface extending along the forefoot, mid and heel portions and on which a person stands, and a lower surface extending along the forefoot, mid and heel portions, the lower surface including a shallow recess, the first layer being made of a material of a first hardness; and a force line insert secured in the recess and having a shape that follows a greatest area of force of the foot on the upper surface during a normal stride, the force line insert being made of a material of a second hardness which is less than the first hardness.  
       [0011] The recess and the force line insert preferably each have a height of approximately 2 mm. Also, the force line insert and the recess have substantially the same shape and dimensions. Preferably, the first layer is made from a urethane foam having a Shore “00” durometer hardness in the range of approximately 45-75, with a more preferred range of approximately 55-65, and with a preferred value of approximately 60, and the force line insert is made from a urethane foam having a Shore “00” durometer hardness in the range of approximately 35-65, with a preferred range of approximately 45-55, and with a preferred value of approximately 50.  
       [0012] The force line insert includes a heel insert portion having a first width for accommodating a heel of the foot during a heel strike and to provide cushioning thereof; a mid insert portion connected at one end with the heel insert portion and which has a second width less than the first width; and a forefoot insert portion connected with an opposite end of the mid insert portion and which has a shape that extends forwardly to a greater extent at a medial side of the insole in correspondence with a positioning of the metatarsals of the foot. Preferably, a forward edge of the forefoot insert portion has an angled arcuate shape.  
       [0013] In addition, the heel portion of the insole is cupped to maintain the heel in the heel portion.  
       [0014] The mid portion includes a medial arch portion positioned adjacent to the mid insole portion. The medial arch portion has a height greater than a remainder of the mid portion, and includes spaced apart, transverse oriented grooves defining transverse flex members therebetween which effectively function as springs.  
       [0015] In accordance with another aspect of the present invention, a full length insole for use with footwear, comprises a forefoot portion extending at least to metatarsals of a foot; a heel portion; a mid portion connecting together the forefoot portion and the heel portion, the mid portion including a medial arch portion; an upper surface extending along the forefoot, mid and heel portions on which a person stands; a lower surface extending along the forefoot, mid and heel portions; a forefoot pillow formed as a raised area at the upper surface at the forefoot portion to provide additional cushioning thereat and shaped to conform to a pressure area of the foot so as to include a front edge that extends forwardly to a greater extent at a medial side of the insole; and a heel pillow formed as a raised area at the upper surface at the heel portion to provide additional cushioning thereat and shaped to enhance progression of a gait to guide the foot toward the medial arch portion.  
       [0016] The forefoot and heel pillows provide an extra thickness of the same material as a remainder of the insole at the forefoot and heel portions, and are formed integrally as a single molded piece therewith. The extra thickness is less than approximately 3 mm.  
       [0017] The heel pillow has a shape of a wing that is oriented rearwardly. The wing has a greater width at a rear portion thereof and tapers in width in a forward direction, while also pointing toward the medial arch portion.  
       [0018] In accordance with still another aspect of the present invention, a full length insole for use with footwear, comprises a first layer including a forefoot portion extending at least to metatarsals of a foot, a heel portion, a mid portion connecting together the forefoot portion and the heel portion, the mid portion including a medial arch portion, an upper surface extending along the forefoot, mid and heel portions on which a person stands, and a lower surface extending along the forefoot, mid and heel portions, the lower surface including a shallow recess, the first layer being made of a material of a first hardness; a force line insert secured in the recess and having a shape that follows a greatest area of force of the foot on the upper surface during a normal stride, the force line insert being made of a material of a second hardness which is less than the first hardness; a forefoot pillow formed as a raised area at the upper surface at the forefoot portion to provide additional cushioning thereat and shaped to conform to a pressure area of the foot so as to include a front edge that extends forwardly to a greater extent at a medial side of the insole; and a heel pillow formed as a raised area at the upper surface at the heel portion to provide additional cushioning thereat and shaped to enhance progression of a gait to guide the foot toward the medial arch portion.  
       [0019] The above and other features of the invention will become readily apparent from the following detailed description thereof which is to be read in connection with the accompanying drawings.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0020]FIG. 1 is a top plan view of a left insole according to the present invention;  
     [0021]FIG. 2 is a top plan view of a right insole according to the present invention;  
     [0022]FIG. 3 is a bottom plan view of the right insole of FIG. 2;  
     [0023]FIG. 4 is a bottom plan view of the left insole of FIG. 1;  
     [0024]FIG. 5 is a cross-sectional view of the left insole, taken along line  5 - 5  of FIG. 1;  
     [0025]FIG. 6 is a cross-sectional view of the left insole, taken along line  6 - 6  of FIG. 1; and  
     [0026]FIG. 7 is a cross-sectional view of the left insole, taken along line  7 - 7  of FIG. 1. 
    
    
     DETAILED DESCRIPTION  
     [0027] As discussed above, there are many working people, such as construction workers, cashiers, etc., that spend most of their working time in a standing position. Further, much of this standing occurs on hard floors, such as concrete floors or the like. This has the tendency to cause lower back pain and lower extremity pain. Further, these people also tend to alter their posture and gait, in an attempt to alleviate this pain.  
     [0028] The present invention is designed to alleviate such lower back pain and lower extremity pain, while enhancing the stance and correct gait of the foot.  
     [0029] Referring to the drawings in detail, a left insole  10  and a right insole  11  according to the present invention are adapted to be placed in articles of footwear, as is well known. Insoles  10  and  11  are particularly adapted to alleviate lower back pain and lower extremity pain. Only the left insole  10  will now be described, with the understanding that right insole  11  will be the mirror image of insole  10 .  
     [0030] Specifically, insole  10  has the shape of a human left foot and therefore includes a curved toe or forefoot portion  12 , a heel portion  14 , and a mid portion  16  which connects forefoot portion  12  and heel portion  14  together. Heel portion  14  has a greater thickness than toe portion  12 . For example, heel portion  14  can have a thickness of about 5-8 mm, while toe portion can have a thickness of about 1-6 mm.  
     [0031] Insole  10  is formed by a lower layer  18  and a top cover  20  secured to the upper surface of lower layer  18 , along forefoot portion  12 , cupped heel portion  14  and mid portion  16 , by any suitable means, such as adhesive, RF welding, etc.  
     [0032] Lower layer  18  can be made from any suitable material including, but not limited to, any flexible material which can cushion and absorb the shock from heel strike on the insole. Suitable shock absorbing materials can include any suitable foam, such as but not limited to, cross-linked polyethylene, poly(ethylene-vinyl acetate), polyvinyl chloride, synthetic and natural latex rubbers, neoprene, block polymer elastomer of the acrylonitrile-butadiene-styrene or styrene-butadienestyrene type, thermoplastic elastomers, ethylenepropylene rubbers, silicone elastomers, polystyrene, polyurea or polyurethane; most preferably a polyurethane foam made from flexible polyol chain and an isocyanate such as a monomeric or prepolymerized diisocyanate based on 4,4′-diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI). Such foams can be blown with freon, water, methylene chloride or other gas producing agents, as well as by mechanically frothing to prepare the shock absorbing resilient layer. Such foams advantageously can be molded into the desired shape or geometry. Non-foam elastomers such as the class of materials known as viscoelastic polymers, or silicone gels, which show high levels of damping when tested by dynamic mechanical analysis performed in the range of −50 degrees C. to 100 degrees C. may also be advantageously employed. A resilient polyurethane can be prepared from diisocyanate prepolymer, polyol, catalyst and stabilizers which provide a waterblown polyurethane foam of the desired physical attributes. Suitable diisocyanate prepolymer and polyol components include polymeric MDI M-10 (CAS 9016-87-9) and Polymeric MDI MM-103 (CAS 25686-28-6), both available from BASF, Parsippany, N.J.; Pluracol 945 (CAS 9082-00-2) and Pluracol 1003, both available from BASF, Parsippany, N.J.; Multrinol 9200, available from Mobay, Pittsburgh, Pa.; MDI diisocyanate prepolymer XAS 10971.02 and polyol blend XUS 18021.00 available from the Dow Chemical Company, Midland, Mich.; and Niax 34-28, available from Union Carbide, Danbury, Conn. These urethane systems generally contain a surfactant, a blowing agent, and an ultra-violet stabilizer and/or catalyst package. Suitable catalysts include Dabco 33-LV (CAS 280-57-9,2526-71-8), Dabco X543 (CAS Trade Secret), Dabco T-12 (CAS 77-58-7), and Dabco TAC (CAS 107-21-1) all obtainable from Air Products Inc., Allentown, Pa.; Fomrez UL-38, a stannous octoate, from the Witco Chemical Co., New York, N.Y. or A-1(CAS 3033-62-3) available from OSI Corp., Norcross, Ga. Suitable stabilizers include Tinuvin 765 (CAS 41556-26-7), Tinuvin 328 (CAS 25973-55-1), Tinuvin 213 (CAS 104810-48-2), Irganox 1010 (CAS 6683-19-8), Irganox 245 (CAS 36443-68-2), all available from the Ciba Geigy Corporation, Greensboro, N.C., or Givsorb UV-1 (CAS 057834-33-0) and Givsorb UV-2 (CAS 065816-20-8) from Givaudan Corporation, Clifton, N.J. Suitable surfactants include DC-5169 (a mixture), DC190 (CAS68037-64-9), DC197 (CAS69430-39-3), DC-5125 (CAS 68037-62-7) all available from Air Products Corp., Allentown Pa. and L-5302 (CAS trade secret) from Union Carbide, Danbury Conn. Alternatively, lower layer  18  can be a laminate construction, that is, a multilayered composite of any of the above materials. Multilayered composites are made from one or more of the above materials such as a combination of polyethylene vinyl acetate and polyethylene (two layers), a combination of polyurethane and polyvinyl chloride (two layers) or a combination of ethylene propylene rubber, polyurethane foam and ethylene vinyl acetate (3 layers).  
     [0033] Preferably, lower layer  18  is made from a urethane molded material.  
     [0034] Top cover  20  can be made from any suitable material including, but not limited to, fabrics, leather, leatherboard, expanded vinyl foam, flocked vinyl film, coagulated polyurethane, latex foam on scrim, supported polyurethane foam, laminated polyurethane film or in-mold coatings such as polyurethanes, styrene-butadiene-rubber, acrylonitrile-butadiene, acrylonitrile terpolymers and copolymers, vinyls, or other acrylics, as integral top covers. Desirable characteristics of top cover  20  include good durability, stability and visual appearance. It is also desirable that top cover  20  have good flexibility, as indicated by a low modulus, in order to be easily moldable. The bonding surface of top cover  20  should provide an appropriate texture in order to achieve a suitable mechanical bond to the upper surface of lower layer  18 . Preferably, the material of top cover  20  is a fabric, such as a brushed knit laminate top cloth (brushed knit fabric/urethane film/non-woven scrim cloth laminate) or a urethane knit laminate top cloth. Preferably, top cover  20  is made from a polyester fabric material.  
     [0035] Lower layer  18  can be prepared by conventional methods such as heat sealing, ultrasonic sealing, radio-frequency sealing, lamination, thermoforming, reaction injection molding, and compression molding and, if necessary, followed by secondary die-cutting or in-mold die cutting. Representative methods are taught, for example, in U.S. Pat. Nos. 3,489,594; 3,530,489 4,257,176; 4,185,402; 4,586,273, in the Handbook of Plastics, Herber R. Simonds and Carleton Ellis, 1943, New York, N.Y., Reaction Injection Molding Machinery and Processes, F. Melvin Sweeney, 1987, New York, N.Y., and Flexible Polyurethane Foams, George Woods, 1982, New Jersey, whose preparative teachings are incorporated herein by reference. Preferably, the innersole is prepared by a foam reaction molding process such as taught in U.S. Pat. No. 4,694,589.  
     [0036] During use, insole  10  is placed in a shoe so that the medial side of mid portion  16  rests against the inside of the shoe. Forefoot portion  12  may end just in front of the metatarsals. However, insole  10  is preferably a full length insole, that is, extends along the entire foot.  
     [0037] Typically, insole  10  would be sized corresponding to shoe sizes and would be provided in sized pairs. Alternatively, insole  10  may be trimmed to the requirements of the user. In this regard, arcuate pattern trim lines  22   a - 22   d  may be formed on the lower surface of forefoot portion  12  of insole  10 , and which are representative of various sizes of the human foot. For example, insole  10  may be provided for a woman&#39;s shoe size of 10-11, with first continuous pattern trim line  22   a  being representative of a smaller size insole for a woman&#39;s shoe size 9, second continuous pattern trim line  22   b  extending around the periphery of toe portion  12  indicative of another size of insole for a woman&#39;s shoe size 8, third continuous pattern trim line  22   c  extending around the periphery of toe portion  12  indicative of another size of insole for a woman&#39;s shoe size 7, and fourth continuous pattern trim line  22   d  extending around the periphery of toe portion  12  indicative of another size of insole for a woman&#39;s shoe size 6. If the user requires a size other than the original large size, the wearer merely trims the insole with a scissors or cutting instrument, using pattern trim lines  22   a - 22   d,  to achieve the proper size. The pattern trim lines may be imprinted by conventional printing techniques, silkscreening and the like. As an alternative, pattern trim lines  22   a - 22   d  may be formed as shallow grooves, or be perforated, so that a smaller size insole may be separated by tearing along the appropriate trim lines, which tearing operation is facilitated by the inclusion of perforations. Thus, forefoot portion  12  can be trimmed so that forefoot portion  12  fits within the toe portion of a shoe.  
     [0038] In accordance with the present invention, insole  10  is formed with a structure to alleviate lower back pain and lower extremity pain. Specifically, insole  10  is provided with a shallow recess  24  about 2 mm deep at the lower surface of lower section  18 . Shallow recess  24  follows the greatest line of force of the foot during a normal stride, that is, in a single limb stance phase. When walking, the foot first impacts at the heel with a large force, for example, up to three times a normal standing force, and then moves toward the forefoot. The heel lifts off of the insole slightly at the position of contact of the mid-foot with the insole and then transfers to the forefoot. At the forefoot, the foot transfers from the position of the fifth metatarsal to the first metatarsal, where push-off occurs at the big toe of the foot.  
     [0039] Shallow recess  24  has a shape to follow this line of force, and to cover the high force areas during this stride.  
     [0040] In accordance with the present invention, a force line insert  26  having a thickness of about 2 mm and having the same shape as shallow recess  24 , is secured within shallow recess. Force line insert  26  is made from a softer or more cushioning material than the remainder of lower section  18  of insole  10 . For example, lower section  18  of insole  10  can be made from a urethane foam having a Shore “00” durometer hardness in the range of approximately 45-75, more preferably in the range of approximately 55-65, and with a preferred hardness of approximately 60, while force line insert  26  can be made from a softer urethane foam having a Shore “00” durometer hardness in the range of approximately 35-65, more preferably in the range of approximately 45-55, and with a preferred hardness of approximately 50. A preferred material for force line insert  26  is the material sold by Rogers Corporation of Rogers, Connecticut under the trademark “PORON”. Preferably, force line insert  26  is formed first, and then placed in a mold, where the remainder of lower section  18  of insole  10  is molded thereon, and thereby bonded to the PORON material of force line insert  26  during the molding operation.  
     [0041] Thus, the force line shape of insert  26  provides a softer material along the center of pressure of the gait line. As a result, force line insert  26  provides cushioning and shock absorption at every point along the stride.  
     [0042] As shown, force line insert  26  includes a heel insert portion  26   a  of a width intended to accommodate the heel during the heel strike and provide cushioning thereof. From heel insert portion  26   a,  insert  26  tapers in width to a mid insert portion  26   b  at mid portion  16 . The reason for the taper is that the cushioning material of insert  26  is not needed as much at this position, since there is more surface area of the foot in contact with the upper surface of insole  10  to spread out the forces more evenly, and because, as will be explained hereinafter, the foot is guided toward medial arch portion  16   a  of mid portion  16  which absorbs much of the forces.  
     [0043] From mid insert portion  26   b,  insert  26  increases in width to a forefoot insert portion  26   c.  Forefoot insert portion  26   c  has a shape that extends forwardly to a greater extent at the medial side of insole  10  in correspondence with the configuration of the metatarsals. As a result, the forward edge of forefoot insert portion  26   c  has an angled arcuate shape.  
     [0044] Thus, with the initial heel strike, heel insert portion  26   a  functions to provide greater cushioning and shock absorbing at the heel. As the foot moves forwardly, there is still a line of contact at the mid-foot, but medial arch portion  16   a  also absorbs much of the force, so as to provide an evening out of the force at the mid-foot. As a result, the width of mid insert portion  26   b  can be reduced. Thereafter, the foot transfers to the forefoot, and particularly, from the fifth metatarsal to the first metatarsal, where push-off occurs at the big toe of the foot. Such force can be up to three times the normal standing force. Forefoot insert portion  26   c  is shaped to follow this line of force, and provide extra cushioning and shock absorbing during this action.  
     [0045] It will be appreciated that heel portion  14  is preferably a cupped heel portion. Specifically, as shown, heel portion  14  includes a relatively flat central portion  14   a,  and a sloped side wall  14   b  that extends around the sides and rear of central portion  14   a.  Generally, when a heel strikes a surface, the fat pad portion of the heel spreads out. The cupped heel portion thereby stabilizes the heel of the person and maintains the heel in heel portion  14 , to prevent such spreading out of the fat pad portion of the heel, and to also prevent any side to side movement of the heel in heel portion  14 . This ensures that heel insole portion  26   a  operates properly on the foot.  
     [0046] With respect to medial arch portion  16   a,  the arch can be built into insole  10  in one of two ways. First, arch portion  16   a  can be filled or built up with a bulky cushioning material. This, however, provides the disadvantage that it might not be capable of use in a shoe already having a built in arch support, since it may be too bulky. Therefore, the preferred manner of forming medial arch portion  16   a  according to the present invention is to build up the height of medial arch portion  16   a,  but to provide spaced apart, transverse oriented grooves or recesses  28  therein, which define transverse flex members  30  therebetween which effectively function as springs. The advantage of using flex members  30  is that the bulk of arch portion  16   a  is not needed and thereby greatly reduced. It therefore becomes easier and better to use flex members  30  with shoes, since they can be used in shoes with or without a built in arch support.  
     [0047] Flex members  30  function in concert with force line insert  26  to provide even cushioning support and shock absorption over the entire mid-foot area during mid-stance phase. Because of flex members  30 , the width of mid insole portion  26   b  can be reduced. The use of flex members  30 , by themselves, however, has been known in insoles sold more than one year ago, but the combination with force line insert  26  is new.  
     [0048] In addition to force line insert  26 , another important feature of the present invention is the addition of forefoot pillow  32  and heel pillow  34 .  
     [0049] Pillows  32  and  34  provide an extra thickness of the same material as lower layer  18  and are formed integrally as a single piece therewith during the molding operation of insole  10 . Pillows  32  and  34  are provided at the two areas with the greatest force. Since the cushioning energy is directly proportional to thickness, the cushioning effect is normally achieved with increasing bulk of the entire insole. The present invention accomplishes this by increasing the bulk slightly by up to approximately 3 mm in thickness above the upper surface of the insole, only at the areas where the greatest forces result during walking.  
     [0050] When walking, the heel of the foot normally hits on the outside of the heel and rolls toward the medial arch. Thus, pillow  34 , in addition, to providing cushioning at the heel, is shaped to enhance the rolling or progression of the gait, and thereby guides the foot toward medial arch portion  16   a.  Thus, heel pillow  34  functions as a guide as well as providing extra cushioning. In this regard, pillow  34  has the shape of a wing that is oriented rearwardly. Thus, pillow  34  has a greater width at the rear portion and tapers in width, while also pointing toward medial arch portion  16   a.    
     [0051] At the forefoot, pillow  32  provides the same two functions. Normally, when walking, the foot moves from the fifth metatarsal to the first metatarsal and then the person pushes off from the big toe. Pillow  32  thereby has a shape similar to forefoot insole portion  26   c,  that is, with an arcuate front edge that extends forwardly to a greater extent at the medial side of insole  10 .  
     [0052] Pillows  32  and  34  thereby enhance the stance and correct walking gait, while also providing cushioning.  
     [0053] Thus, while force line insert  26  provides cushioning and shock absorption at every point, pillows  32  and  34  provide a different function of shock absorption where needed, as well as a biomechanical effect in aiding the foot in rolling through the gait.  
     [0054] Tests were performed with insoles  10  and  11 . Specifically, 103 people were evaluated over a four week period with insoles  10  and  11 .  
     [0055] The following Table I shows a four week period of people wearing insoles  10  and  11  on a visual analog scale (VAS), which is a widely accepted method for evaluating pain.  
                                   TABLE I                                   Variable   Number of   Mean VAS   Standard           (Back Pain)   Subjects   Score   Deviation                          Baseline   104   57.57   14.89           (week 0)           Week 1   103   37.17   20.12           Week 2   103   30.81   19.93           Week 4   103   22.48   20.50                      
 
     [0056] It will be appreciated that the back pain significantly decreased from the baseline to week 1, and continued to decrease thereafter to week 4. Similar tests with conventional insoles show that, although many insoles normally relieve some pain, the present invention works faster and better than conventional insoles that provide shock absorption. Thus, the results of the tests with insoles  10  and  11  showed significant relief of lower back pain and lower extremity pain.  
     [0057] The change in back pain VAS score from the baseline is shown by the following Table II:  
                                   TABLE II                                   Variable                       (Change in           Back pain   Mean change   Standard           VAS)   in VAS score   Deviation   Prob &gt; |T|                          Week 1 from   20.19   22.15   0.0001           Baseline           Week 2 from   26.81   22.93   0.0001           Baseline           Week 4 from   35.14   23.90   0.0001           Baseline                      
 
     [0058] In Table II, the designation Prob&gt;|T| refers to the probability that the data is significantly accurate and relevant. The small percentage confirms the accuracy and relevancy of the data.  
     [0059] The same analysis was performed with the lower extremity pain, and is presented in Tables III and IV below:  
                                   TABLE III                                   Variable                       (Lower           Extremity   Number of   Mean VAS   Standard           Pain)   Subjects   Score   Deviation                          Baseline   104   35.56   23.00           (week 0)           Week 1   103   27.13   20.43           Week 2   103   25.32   22.10           Week 4   103   19.94   21.50                      
 
     [0060]                                   TABLE IV                                   Variable                       (Change in           Lower           Extremity   Mean change Standard           Pain VAS)   in VAS score   Deviation   Prob &gt; |T|                          Week 1 from    8.01   21.19   0.0002           Baseline           Week 2 from   10.07   23.03   0.0001           Baseline           Week 4 from   15.46   24.15   0.0001           Baseline                        
     [0061] Subjective tests were also performed. At baseline week 0, 98% of the subjects considered insoles  10  and  11  moderately, very or extremely comfortable. At week 4, 92.3% considered the insoles moderately, very or extremely effective in relieving pain. Also, at week 4, over 80% of the subjects considered that insoles  10  and  11  were moderately, very or extremely effective in relieving tired, achy feet (83.5%) as well as tired, achy legs (81.3%).  
     [0062] Thus, insoles  10  and  11  provided significant relief of lower back pain and lower extremity pain after only one week, with further decreases in pain in weeks 2 and 4.  
     [0063] Although the present invention uses the term insole, it will be appreciated that the use of other equivalent or similar terms such as innersole or insert are considered to be synonymous and interchangeable, and thereby covered by the present claimed invention.  
     [0064] Further, although the present invention has been described in connection with insoles, the present invention can be incorporated directly into the sole of a shoe, and the present invention is intended to cover the same. In this regard, reference is made in the claims to a full length insole for use with footwear, which can include a removable insole or an insole built into a shoe.  
     [0065] Having described specific preferred embodiments of the invention with reference to the accompanying drawings, it will be appreciated that the present invention is not limited to those precise embodiments and that various changes and modifications can be effected therein by one of ordinary skill in the art without departing from the scope or spirit of the invention as defined by the appended claims.