Patent Publication Number: US-7584556-B2

Title: Footgear and insole

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to footgear including shoes, Japanese geta clogs, slippers, sandals, high heels, and socks, and insoles. 
     Typically, a heel support formed in footgear or an insole for supporting the heel has an upper surface that is shaped substantially flat or concave in a dish-like manner. As proposed in Japanese Laid-Open Patent Publication No. 2000-83706, a number of projections may project from the upper surface of the heel support. This structure presses and stimulates the bottom surface of the heel, thus promoting blood circulation in the foot. 
     Japanese Utility Model No. 3026518 discloses an insole for footgear. The insole includes a heel support with a magnet, which presses and stimulates the bottom surface of the heel. Further, Japanese Utility Model No. 3075369 discloses a sock. The sock includes a heel support with a plate-like body, which presses and stimulates the bottom surface of the heel. 
     Further, footgear or an insole having a shock absorbing material that is provided in a heel support is publicly known. 
     Normally, as shown in  FIG. 9 , a human sole includes an inner longitudinal arch A 1  located closest to the big toe, an outer longitudinal arch A 2  located closest to the little toe, and a lateral arch A 3  extending from the base of the big toe to the base of the little toe. The arches A 1  to A 3  are formed through actions of bones and muscles and form a substantially triangular shape, as viewed from above. However, as the functions of the muscles and tendons of the foot are weakened by aging or illness, the arches A 1  to A 3  may deform to cause a flatfoot, a clubfoot, a valgus foot, a metatarsus latus, or a bowleg. In walking, flexing motion of the arches A 1  to A 3  promotes the blood circulation (pumping action) of the foot. Such blood circulation is decreased by the deformation of the arches A 1  to A 3 . Also, the deformation of the arches A 1  to A 3  increases impact acting on the bone structure of the foot when the heel hits the ground. This increases fatigability of the foot in walking. 
     The heel supports formed in the conventional footgear and insole press and stimulate the bottom surface of the heel, but cannot correct the deformed arches A 1  to A 3 . 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an objective of the present invention to provide footgear and insoles that correct the shape of the arch of the sole. 
     To achieve the foregoing and other objectives and in accordance with the purpose of the present invention, the invention provides footgear having a sole support that supports the sole of the foot. The sole support includes a heel support supporting the heel. The footgear includes a projection formed on the heel support for pressing and stimulating a nerve in the proximity of the tuber calcanei of the foot. 
     The present invention also provides an insole having a sole support that supports the sole of the foot. The sole support includes a heel support that supports the heel. The insole includes a projection provided on the heel support for pressing and stimulating a nerve in the proximity of the tuber calcanei of the foot. 
     Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which: 
         FIG. 1  is a plan view showing an insole according to an embodiment of the present invention; 
         FIG. 2  is a bottom view showing the insole of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view taken along line A-A of  FIG. 1 ; 
         FIG. 4  is a bottom view showing a heel support of the insole of  FIG. 1 ; 
         FIG. 5  is a cross-sectional view showing a shoe including the insole of  FIG. 1  in a usable state; 
         FIG. 6  is a diagram representing the bone structure and the muscles of a human lower body; 
         FIG. 7  is a diagram representing the bone structure and the nerves of a human lower limb; 
         FIG. 8  is a diagram representing the bone structure and the blood vessels of a human foot as viewed from the sole; 
         FIG. 9  is a perspective view showing an arch of a human sole; 
         FIGS. 10A to 10L  are plan views showing projections of insoles according to different embodiments of the present invention; 
         FIG. 11  is a cross-sectional view showing an insole according to another embodiment of the present invention; 
         FIG. 12  is a cross-sectional view showing a shoe according to another embodiment of the present invention; 
         FIGS. 13A and 13B  are cross-sectional views showing name sheets and projections of insoles according to different embodiments of the present invention; 
         FIG. 14  is a partially exploded side view showing a sock according to another embodiment of the present invention; 
         FIG. 15  is a bottom view showing an insole according to another embodiment of the present invention; 
         FIGS. 16 and 17  are perspective views showing portions of insoles according to different embodiments of the present invention; and 
         FIG. 18  is a cross-sectional view showing an insole according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an embodiment of the present invention will be described with reference to  FIGS. 1 to 9 . 
     Referring to  FIG. 1 , an insole  11  of the illustrated embodiment has an upper surface that, as a whole, functions as a sole support for supporting the sole of a human foot. The upper surface of the insole  11  includes five toe supports that support the corresponding toe fingers and a heel support  11   a  that supports the heel. The insole  11  includes a body sheet  12  having a shape that substantially coincides with the shape of the sole. The body sheet  12  is made of fabric such as woven fabric, knitted fabric, and unwoven fabric, which is formed of natural fiber including cotton and wool or synthetic fiber. As shown in  FIG. 3 , a masking sheet  13  is bonded with the upper surface of the body sheet  12  by an adhesive agent  14 . The masking sheet  13  is formed of, for example, artificial leather that is subjected to antimicrobial and deodorant treatment. A name sheet  15  is secured to a substantially entire portion of a portion of the upper surface of the masking sheet  13  corresponding to the heel support  11   a  of the insole  11  through sewing by a machine-sewing thread  16  or bonding by an adhesive agent. The name sheet  15  is formed of, for example, artificial or natural leather. 
     As shown in  FIGS. 3 and 4 , a projection  17  having a plate-like shape is bonded with the bottom surface of the insole  11  by an adhesive agent  18 . The projection  17  is formed by a synthetic resin sheet body, a synthetic resin molded body, or a synthetic resin foamed body, which is formed of, for example, polyurethane resin, vinyl chloride resin, acrylic resin, polyethylene resin, or polypropylene resin. As shown in  FIG. 4 , the projection  17  has an equilateral hexagonal shape as viewed from above. The length of a tangential line L including the center O 2  of the hexagonal shape, or the diameter F of a circle circumscribed around the hexagonal shape, is preferably 3 to 28 millimeters, more preferably 5 to 25 millimeters, further preferably 8 to 25 millimeters, and most preferably 12 to 22 millimeters. In the illustrated embodiment, the length of the tangential line L is set to 15 millimeters. The projection amount (the height) t of the projection  17  of  FIG. 3  is preferably 0.2 to 6.0 millimeters, more preferably 0.4 to 4.0 millimeters, further preferably 0.7 to 2.4 millimeters, and most preferably 1.0 to 2.2 millimeters. In the illustrated embodiment, the projection amount t is set to 1.8 millimeters. If the projection  17  is formed by, for example, a compressible foamed body, the projection  17  is formed in such a manner that the projection amount t of the projection  17  becomes the aforementioned values in a state compressed by the weight of the wearer. The projection amount t of the projection  17  in a state not compressed by the weight of the wearer is not limited. In a state not compressed by the weight of the wearer, for example, the projection amount t of the projection  17  of the insole  11  that is used in a athletic shoe may be 2 to 4 times the projection amount t of the projection  17  of the insole  11  that is used in a shoe other than the athletic shoe. In other words, in the case of the athletic shoe, the projection amount t of the projection  17  is determined in consideration of the fact that the projection is compressed to between one-quarter and one-half by the weight of a wearer of the footgear. 
     In the illustrated embodiment, referring to  FIG. 4 , the center O 2  of the projection  17  coincides with the center O 1  of the heel support  11   a  of the insole  11 . However, the center O 2  may be located offset from the center O 1  rightward or leftward along a direction defined by a width W and by a margin not greater than 4.5 millimeters. Alternatively or in addition to this, the center O 2  may be located offset from the center O 1  frontward or rearward by a margin not greater than 8 millimeters. 
     Normally, referring to  FIG. 4 , the center O 1  of the heel support  11   a  is located at the center of a lateral direction defined by the width of the insole  11  and offset frontward from a rear end E of the insole  11  by a predetermined margin (generally, 14 to 28 millimeters). However, if the center of a calcaneus  37  (the center O 37  of a tuber calcanei  37   a  of  FIG. 8 ) does not coincide with the center O 1  of the heel support  11   a , the center O 1  of the heel support  11   a  is moved to the position coinciding with the center of the calcaneus  37 . The center O 2  of the projection  17  is then arranged at the position coinciding with the center O 1 . Alternatively, the center O 2  of the projection  17  may be set to the position offset from the center O 1  of the heel support  11   a  rightward or leftward along the direction defined by the width W by a margin not greater than 4.5 millimeters and/or frontward or rearward by a margin not greater than 8 millimeters. 
     As shown in  FIG. 5 , a shoe  21  includes a bottom material (a heel material)  22  that supports a foot  30 . The lower end of a cover portion  23  that covers a heel  30   a  of the foot  30  is bonded with the upper peripheral end of the bottom material  22  by an adhesive agent. An inner bottom  24  is bonded with the upper surface of the bottom material  22  by an adhesive agent. The insole  11  is received in the shoe  21  as mounted on the inner bottom  24 . The heel  30   a  of the foot  30  is thus covered by the heel support  11   a  and the cover portion  23 . Referring to  FIG. 5 , an upper surface section of the insole  11  corresponding to the projection  17  becomes elevated when the insole  11  receives the weight of the wearer of the shoe  21 . This stimulates a part of the foot  30  in the proximity of the tuber calcanei  37   a.    
     There are different nerves in the proximity of the tuber calcanei  37   a , including lower end portions (termini) of a tibial nerve  51  and a medial sural cutaneous nerve  53 , which are automatic nerves vertically extending along rear sides of a tibia  34 , a talus  36 , and the calcaneus  37 . Thus, the elevated portion of the insole  11  corresponding to the projection  17  stimulates the nerves including the tibial nerve  51  and the medial sural cutaneous nerve  53 . It has been found by a test that stimulation of the tibial nerve  51  and the medial sural cutaneous nerve  53  promotes blood circulation, which is a significant effect. The effect will hereafter be explained. 
     The anatomy of a leg  29  and that of the foot  30  will hereafter be explained with reference to  FIGS. 6 to 9 . 
       FIGS. 6 and 7  illustrate the lower body including the leg  29  and the foot  30 . More specifically, the leg  29  includes a thigh bone  33 , the tibia  34 , and a fibula  35 . The foot  30  includes the talus  36 , the calcaneus  37 , and a group of toe bones  38 .  FIGS. 6 and 7  also show a spine  31 , a pelvis  32 , a musculus gluteus maximus  41 , a quadriceps muscle of thigh  42 , a biceps muscle of thigh  43 , a musculus gastrocnemius  44 , an Achilles tendon  45 , a frontal tibial muscle  46 , the tibial nerve  51 , a common peroneal nerve  52 , and the medial sural cutaneous nerve  53 . Although not illustrated, the common peroneal nerve  52  is divided into a superficial peroneal nerve and a deep peroneal nerve in the frontal side of the leg  29 . 
       FIG. 8  shows the toe bones  38 , which are connected to the calcaneus  37 . More specifically, the drawing illustrates a navicular bone  56 , a cuboid bone  57 , a first cuneiform bone  58 , a second cuneiform bone  59 , a third cuneiform bone  60 , a first group of toe bones  61 , a second group of toe bones  62 , a third group of toe bones  63 , a fourth group of toe bones  64 , and a fifth group of toe bones  65 . Referring to the drawing, the line L 1  includes the center O 37  of the tuber calcanei  37   a  (the center O 1  of the heel support  11   a ) and the center O 3  of a distal portion of the first group of toe bones  61  (the center O 3  of a first toe support portion shown in  FIG. 2 ). The line L 2  includes the center O 37  of the tuber calcanei  37   a  and the center O 4  of a distal portion of the second group of toe bones  62  (the center O 4  of a second toe support portion shown in  FIG. 2 ). The line L 5  includes the center O 37  of the tuber calcanei  37   a  and the center O 5  of a distal portion of the fifth group of toe bones  65  (the center O 5  of a fifth toe support portion shown in  FIG. 2 ). The projection  17  is oriented in such a manner that the extending line L′ of one diagonal line L of the projection  17  that includes the center O 2  extends preferably between the line L 1  and the line L 5 , and more preferably on a midline between the line L 1  and the line L 2 . 
     As shown in  FIG. 9 , the inner longitudinal arch A 1  extends between the center O 37  of the tuber calcanei  37   a  and a distal portion of a first metatarsal bone  61   a  of the first group of toe bones  61 . The outer longitudinal arch A 2  extends between the center O 37  of the tuber calcanei  37   a  and a distal portion of a fifth metatarsal bone  65   a  of the fifth group of toe bones  65 . The lateral arch A 3  extends between the distal portion of the first metatarsal bone  61   a  and the distal portion of the fifth metatarsal bone  65   a.    
     The projection  17  stimulates the termini of the tibial nerve  51  and the medial sural cutaneous nerve  53 , which are located in the proximity of the tuber calcanei  37   a . The effect produced by such stimulation will hereafter be described with reference to  FIGS. 5 to 8 . 
     As shown in  FIG. 6 , the musculus gluteus maximus  41 , the quadriceps muscle of thigh  42 , the biceps muscle of thigh  43 , the musculus gastrocnemius  44 , and the frontal tibial muscle  46  are connected to the tibial nerve  51  and the medial sural cutaneous nerve  53 . Accordingly, the stimulation of the termini of the tibial nerve  51  and the medial sural cutaneous nerve  53  by the projection  17  corrects flaccidity of the muscles  41 ,  42 ,  43 ,  44 ,  46 , thus normalizing the positions of the muscles  41  to  44  and  46 . This normalizes movement of the muscles  41  to  44  and  46 , relieving the associated arteries and veins from pressure. The actions of these vessels are thus normalized. Further, normalized movement of the musculus gluteus maximus  41  restores the normal lateral equilibrium in the pelvis  32 . The erector muscle of spine, the broadest muscle of back, and the trapezius muscle (neither is shown) are also normalized, thus normalizing the function of the spine. This promotes the systemic blood circulation and activates the automatic nervous system. 
     Further, the stimulation of the tibial nerve  51  and the medial sural cutaneous nerve  53  normalizes the position of the Achilles tendon  45 , which is connected to the musculus gastrocnemius  44 , as shown in  FIG. 6 . This corrects the deformed shapes of the arches A 1  to A 3 , allowing a smooth weight shift in walking. A plantar artery  66 , a plantar vein  67  and a plantar arch  68  of  FIG. 8 , and toe capillaries are also stimulated through the stimulation of the tibial nerve  51  and the medial sural cutaneous nerve  53 . This promotes the blood circulation of the foot  30  in walking. Further, the impact acting on the bone structure of the foot  30  when the heel  30   a  hits the ground is reduced, thus relieving the fatigability of the foot  30  in walking. 
     In order to prove the effect of the projection  17  formed in the insole  11 , a test was carried out in the following manner. 
     The test was performed using the insoles  11  configured differently for examples 1 to 5 and comparative example 1. More specifically, the insole  11  of example 1 had the projection  17  formed in such a manner that the center O 2  of the projection  17  coincided with the center O 1  of the heel support  11   a . The insole  11  of example 2 had the projection  17  formed in such a manner that the center O 2  of the projection  17  was located offset frontward from the center O 1  of the heel support  11   a  by a margin of four millimeters. The insole  11  of example 3 had the projection  17  formed in such a manner that the center O 2  of the projection  17  was located offset frontward from the center O 1  of the heel support  11   a  by a margin of eight millimeters. The insole  11  of example 4 had the projection  17  formed in such a manner that the center O 2  of the projection  17  was located offset rearward from the center O 1  of the heel support  11   a  by the margin of four millimeters. The insole  11  of example 5 had the projection  17  formed in such a manner that the center O 2  of the projection  17  was located offset rearward from the center O 1  of the heel support  11   a  by the margin of eight millimeters. The insole  11  of comparative example 1 does not have the projection  17 . The projections  17  of examples 1 to 5 each have an equilateral hexagonal cross-sectional shape. The diameter F of a circle circumscribed around the hexagonal shape is 15 millimeters. The projections  17  are formed by cutting a slightly foamed sheet of polyurethane resin. The projection amount t of each projection  17  is set to 1.5 millimeters in a state compressed by the weight of the wearer. 
     The test was performed using the shoes that incorporate the insoles  11  of examples 1 to 5 and comparative example 1. For each one of the examples, a test subject wore the corresponding pair of shoes and walked 200 steps. After an interval of several minutes, different measurements were taken. The results are shown in Tables 1 and 2. Table 2 shows the ratio of low frequency component (LF) with respect to the high frequency component (HF) as an indicator of sympathetic nerve activity and the HF as an indicator of parasympathetic nerve activity for each example. The values were obtained through variable spectrum analysis using fast Fourier transformation based on four types of data, which are electrocardiogram, respiration rate, heart rate, and blood pressure. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Average Heart Rate 
                 Blood Pressure (Systolic) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 60/min. 
                 97 mmHg 
               
               
                   
                 example 1 
               
               
                   
                 Example 1 
                 66/min. 
                 119 mmHg  
               
               
                   
                 Example 2 
                 60/min. 
                 100 mmHg  
               
               
                   
                 Example 3 
                 60/min. 
                 96 mmHg 
               
               
                   
                 Example 4 
                 62/min. 
                 98 mmHg 
               
               
                   
                 Example 5 
                 60/min. 
                 94 mmHg 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
             
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 Sympathetic Nerve 
                 Parasympathetic Nerve 
               
               
                   
                 Activity (LF/HF) 
                 Activity (HF) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 0.857 
                 0.085 
               
               
                   
                 example 1 
               
               
                   
                 Example 1 
                 1.567 
                 0.043 
               
               
                   
                 Example 2 
                 0.935 
                 0.068 
               
               
                   
                 Example 3 
                 0.923 
                 0.067 
               
               
                   
                 Example 4 
                 0.946 
                 0.073 
               
               
                   
                 Example 5 
                 0.943 
                 0.079 
               
               
                   
                   
               
            
           
         
       
     
     As is clear from Table 2, the sympathetic nerve activity (LF/HF) was increased and the parasympathetic nerve activity (HF) was decreased in examples 1 to 5 compared to comparative example 1. Increase of the sympathetic nerve activity and decrease of the parasympathetic nerve activity were pronounced particularly in example 1 in which the center O 2  of the projection  17  coincides with the center O 1  of the heel support  11   a , or the center O 37  of the tuber calcanei  37   a  of the foot  30 . The increase of the sympathetic nerve activity and the decrease of the parasympathetic nerve activity are thought to be attributed to stimulation of the lateral plantar nerve (the tibial nerve  51  and the common peroneal nerve  52 ) by the projection  17 . 
     As indicated by Table 1, the heart rate and the blood pressure were increased in example 1 compared to comparative example 1. The fact indicates increase of the blood flow. Contrastingly, no significant differences of the heart rate and the blood pressure were noted between examples 2 to 5 and comparative example 1. In examples 2 to 5, the projection  17  was located offset frontward or rearward. Accordingly, it has been confirmed preferable that the projection  17  be formed in such a manner that the center O 2  of the projection  17  coincides with the center O 1  of the heel support  11   a.    
     Next, in order to observe differences of effects caused by differently shaped projections  17 , the following test was performed. In the test, the insole  11  of comparative example 2 had no projection  17 . The insoles  11  of the other examples had the projections  17  having an equilateral triangular shape (example 6), a square shape (example 7), an equilateral pentagonal shape (example 8), an equilateral hexagonal shape (example 9), an equilateral heptagonal shape (example 10), an equilateral octagonal shape (example 11), an equilateral enneagonal shape (example 12), and a circular shape (example 13) as viewed from above. The test was performed using the shoes incorporating the insoles  11  of examples 6 to 13 and comparative example 2. More specifically, a test subject wore the corresponding pair of shoes and walked 200 steps for each of the examples. After an interval of several minutes, different measurements were taken. The result is shown in Tables 3 and 4. In examples 6 to 13, the projections  17  were formed of polyurethane resin through molding in a slightly foamed manner. In each of the examples 6 to 12, the diameter of the circle circumscribed around the projection  17  as viewed from above was 15 millimeters. Similarly, in example 13, the diameter of the circular shape of the projection  17  as viewed from above was 15 millimeters. The projection amount t of the projection  17  of each of examples 6 to 13 was 1.8 millimeters in a state compressed by the weight of the wearer. In examples 6 to 13, the center O 2  of the projection  17  coincided with the center O 1  of the heel support  11   a . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 3 
               
               
                   
                   
               
               
                   
                 Average Heart Rate 
                 Blood Pressure (Systolic) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 60/min. 
                  97 mmHg 
               
               
                   
                 example 2 
               
               
                   
                 Example 6 
                 61/min. 
                  95 mmHg 
               
               
                   
                 Example 7 
                 60/min. 
                 100 mmHg 
               
               
                   
                 Example 8 
                 67/min. 
                 117 mmHg 
               
               
                   
                 Example 9 
                 70/min. 
                 120 mmHg 
               
               
                   
                 Example 10 
                 66/min. 
                 110 mmHg 
               
               
                   
                 Example 11 
                 68/min. 
                 118 mmHg 
               
               
                   
                 Example 12 
                 60/min. 
                 100 mmHg 
               
               
                   
                 Example 13 
                 60/min. 
                  97 mmHg 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
             
               
                   
                 TABLE 4 
               
               
                   
                   
               
               
                   
                 Sympathetic Nerve 
                 Parasympathetic Nerve 
               
               
                   
                 Activity (LF/HF) 
                 Activity (HF) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 0.857 
                 0.085 
               
               
                   
                 example 2 
               
               
                   
                 Example 6 
                 1.211 
                 0.063 
               
               
                   
                 Example 7 
                 1.223 
                 0.063 
               
               
                   
                 Example 8 
                 1.235 
                 0.065 
               
               
                   
                 Example 9 
                 1.689 
                 0.035 
               
               
                   
                 Example 10 
                 1.245 
                 0.059 
               
               
                   
                 Example 11 
                 1.233 
                 0.059 
               
               
                   
                 Example 12 
                 1.172 
                 0.063 
               
               
                   
                 Example 13 
                 1.157 
                 0.072 
               
               
                   
                   
               
            
           
         
       
     
     As indicated by Table 3, the heart rate and the blood pressure were increased in example 9 compared to comparative example 2. Also, as shown in Table 4, the sympathetic nerve activity was increased and the parasympathetic nerve activity was decreased in examples 6 to 13 compared to comparative example 2. Increase of the sympathetic nerve activity and decrease of parasympathetic nerve activity were pronounced particularly in example 9, in which the projection  17  had the equilateral hexagonal shape as viewed from above. Accordingly, it has been concluded that the projection  17  preferably has an equilateral hexagonal shape as viewed from above. 
     Generally, it is believed optimal that, after the heel  30   a  hits the ground, the center of gravity of a walker shifts from the center O 1  of the tuber calcanei  37   a  toward the midpoint between the center O 3  of the distal portion of the first group of toe bones  61  and the center O 4  of the second group of toe bones  62 . For ensuring such shift of the center of gravity, it is preferred that the projection  17  have the equilateral hexagonal shape as viewed from above and that the extending line L′ of one diagonal line L of the projection  17  that includes the center O 2  extends on the midline between the lines L 1 , L 2 . That is, it is assumed that, in walking, this configuration particularly improves the stimulation efficiency of the tibial nerve  51  and the medial sural cutaneous nerve  53  by a point  17   b  of the projection  17 , which is shown in  FIG. 4 . 
     Further, in order to observe differences of effects brought about by the projections  17  having different projection amounts t, the following test was carried out. In the test, the insole  11  of comparative example 3 has no projection  17 . The insoles  11  of the other examples had the projection amounts t that were 0.2 millimeters (example 14), 0.5 millimeters (example 15), 0.8 millimeters (example 16), 1.8 millimeters (example 17), 2.2 millimeters (example 18), 2.8 millimeters (example 19), 3.5 millimeters (example 20), 4.0 millimeters (example 21), and 6.0 millimeters (example 22), in states compressed by the weight of the wearer. The test was performed with the shoes incorporating the insoles  11  of examples 14 to 22 and comparative example 3. More specifically, for each of the example, a test subject wore the corresponding pair of shoes and walked 200 steps. After an interval of several minutes, different measurements were taken. The results are shown in Tables 5 and 6. The projections  17  of examples 14 to 22 had the equilateral hexagonal shapes as viewed from above and the diameter F of the circle circumscribed around the hexagonal shape of each projection  17  was 15 millimeters. The projections  17  were each formed of polyurethane resin through molding in a slightly foamed manner. In examples 14 to 22, the center O 2  of the projection  17  coincides with the center O 1  of the heel support  11   a . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 5 
               
               
                   
                   
               
               
                   
                 Average Heart Rate 
                 Blood Pressure (Systolic) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 60/min. 
                  97 mmHg 
               
               
                   
                 example 3 
               
               
                   
                 Example 14 
                 62/min. 
                  98 mmHg 
               
               
                   
                 Example 15 
                 60/min. 
                 100 mmHg 
               
               
                   
                 Example 16 
                 62/min. 
                  99 mmHg 
               
               
                   
                 Example 17 
                 72/min. 
                 122 mmHg 
               
               
                   
                 Example 18 
                 64/min. 
                 102 mmHg 
               
               
                   
                 Example 19 
                 63/min. 
                 106 mmHg 
               
               
                   
                 Example 20 
                 63/min. 
                 100 mmHg 
               
               
                   
                 Example 21 
                 63/min. 
                 100 mmHg 
               
               
                   
                 Example 22 
                 62/min. 
                 100 mmHg 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
               
               
             
               
                   
                 TABLE 6 
               
               
                   
                   
               
               
                   
                 Sympathetic Nerve 
                 Parasympathetic Nerve 
               
               
                   
                 Activity (LF/HF) 
                 Activity (HF) 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Comparative 
                 0.857 
                 0.085 
               
               
                   
                 example 3 
               
               
                   
                 Example 14 
                 0.883 
                 0.082 
               
               
                   
                 Example 15 
                 0.965 
                 0.069 
               
               
                   
                 Example 16 
                 0.979 
                 0.067 
               
               
                   
                 Example 17 
                 1.489 
                 0.032 
               
               
                   
                 Example 18 
                 1.194 
                 0.066 
               
               
                   
                 Example 19 
                 1.192 
                 0.064 
               
               
                   
                 Example 20 
                 1.189 
                 0.059 
               
               
                   
                 Example 21 
                 1.143 
                 0.060 
               
               
                   
                 Example 22 
                 1.156 
                 0.062 
               
               
                   
                   
               
            
           
         
       
     
     As indicated by Table 6, the sympathetic nerve activity was increased and the parasympathetic nerve activity was decreased in examples 14 to 22 compared to comparative example 3. Increase of the sympathetic nerve activity and decrease of the parasympathetic nerve activity were pronounced particularly in example 17, in which the projection amount t of the projection  17  is 1.8 millimeters. Further, as is clear from Table 5, the heart rate and the blood pressure were increased in example 17 compared to comparative example 3. Accordingly, it has been concluded preferable that the projection amount t of the projection  17  be 1.8 millimeters. The human skin is formed of three layers, or epidermis, dermis, and subcutaneous tissue. The thickness of the epidermis is approximately 0.12 millimeters, the thickness of the dermis is approximately 1.8 millimeters, and the thickness of the subcutaneous tissue is approximately 0.08 millimeters. The total of thicknesses of the three layers, or the thickness of the skin, is thus approximately 2 millimeters. Accordingly, it is preferred that the projection amount t of the projection  17  be slightly smaller than the thickness of the skin. 
     The illustrated embodiment may be modified as follows. 
     As shown in  FIGS. 10A to 10L , the projection  17  may have an equilateral triangular shape, a square shape, an equilateral pentagonal shape, an equilateral heptagonal shape, an equilateral octagonal shape, an equilateral enneagonal shape, an equilateral decagonal shape, a circular shape, an oval shape, a star shape, a rhomboidal shape, or a rectangular shape, as viewed from above. If the projection  17  has a polygonal shape as viewed from above, it is preferred that the extending line L′ of one diagonal line L that includes the center and a corresponding point of the polygonal shape extend on the midline between the lines L 1  and L 5 . If the projection  17  has the oval shape as viewed from above, it is preferred that the extending line L′ of the longitudinal axis of the oval extend on the midline between the lines L 1  and L 5 . If the projection  17  has the rectangular shape of  FIG. 10L  as viewed from above, it is preferred that the longitudinal axis J of the rectangle extend on the midline between the lines L 1  and L 5 . Further, if the projection  17  has the equilateral polygonal shape as viewed from above, the diameter F of the circle circumscribed around the polygon is preferably 3 to 28 millimeters, more preferably 5 to 25 millimeters, further preferably from 8 to 25 millimeters, and most preferably 12 to 22 millimeters. If the projection  17  has the circular shape as viewed from above, it is preferred that the diameter of the circle is set in the same manner as the diameter F. If the projection  17  has the oval shape as viewed from above, it is preferred that the length F of the longitudinal axis of the oval is set in the same manner as the diameter F. If the projection  17  has the star shape of  FIG. 10J  as viewed from above, it is preferred that the length F of the diagonal line L including the center of the star is set in the same manner as the diameter F. If the projection  17  has the rhomboidal shape as viewed from above, it is preferred that the length F of a longer diagonal line L including the center of the rhomboidal is set in the same manner as the diameter F. 
     As shown in  FIG. 11 , the projection  17  may be arranged between the masking sheet  13  and the name sheet  15 . In this case, the name sheet  15  may be secured to the masking sheet  13  around the projection  17  through sewing by the machine-sewing thread  16  or bonding by the adhesive agent. 
     As shown in  FIG. 12 , a recess  22   b  may be formed in an upper surface  22   a  of the bottom material  22  of the shoe  21 . In this case, a projecting portion  17   c  is provided on the lower surface of the projection  17 . The projection  17  is thus secured to the shoe  21  by fitting the projecting portion  17   c  in the recess  22   b . Alternatively, although not illustrated, the projection  17  may be bonded directly with the upper surface of the bottom material  22  of the shoe  21  or the inner bottom  24  using an adhesive agent. 
     As shown in  FIGS. 13A and 13B , the upper or lower surface of the projection  17  may be formed in a convex shape in a spike-like manner or in a concave shape. 
     As shown in  FIG. 14 , the projection  17  may be formed in a sock  71  as footgear using a cloth  72  and a thread  73 . In this case, it is preferred that at least a heel portion of the sock  71  be formed of material having relatively low flexibility. This adapts the position of the projection  17  to an optimal position. 
     Referring to  FIG. 15 , a projection  19 A may be provided in a portion of the insole  11  corresponding to a fourth common plantar digital nerve  75 . The projection  19 A may have a plate-like shape. Further, the position of the projection  19 A relative to the sole support may be changeable. The fourth common plantar digital nerve  75  is located between the fifth group of toe bones  65  and the fourth group of toe bones  64  and connected to the lateral plantar nerve. The projection  19 A stimulates the fourth common plantar digital nerve  75 . Such stimulation normalizes the functions of the muscles and the plantar arch  68  (see  FIG. 8 ) of each lower limb, promoting the blood circulation. 
     Alternatively or in addition to this, a projection  19 B may be provided in a portion of the insole  11  corresponding to a third common plantar digital nerve  76 . The projection  19 B may have a plate-like shape. Further, the position of the projection  19 B relative to the sole support may be changeable. The third common plantar digital nerve  76  is located between the fourth group of toe bones  64  and the third group of toe bones  63  and connected to the medial plantar nerve. The projection  19 B stimulates the third common plantar digital nerve  76 . Such stimulation normalizes the functions of the muscles and the plantar arch  68  ( FIG. 8 ) of each lower limb, promoting the blood circulation. 
     The projections  19 A and  19 B each may have a rectangular shape, a parallelogrammatic shape, or a crescent shape as viewed from above, instead of the shapes shown in  FIG. 15 . 
     The projection  17  may be formed by a group of small projections  17   d  as shown in  FIG. 16  or by a combination of a hexagonal ring  17   e  and a small projection  17   f  as shown in  FIG. 17 . The small projection  17   f  may be a permanent magnet. 
     Referring to  FIG. 18 , the projection  17  may be secured to the body sheet  12  using a hook-and-loop fastener  81 . More specifically, a hook portion  82  is applied to the body sheet  12  and a loop portion  83  is applied to the projection  17 . This structure makes it easy for the wearer to change the position of the projection  17  in such a manner that the center O 2  of the projection  17  coincides with the center O 37  of the tuber calcanei  37   a.    
     A plurality of recesses may be defined in the upper surface of the bottom material  22  of the shoe  21  while a single projection is provided on the bottom surface of the projection  17 . The projection  17  is secured to the shoe  21  by fitting the projection  17  in one of the recesses. This structure makes it easy for the wearer to change the position of the projection  17  in such a manner that the center O 2  of the projection  17  coincides with the center O 37  of the tuber calcanei  37   a.    
     The projection  17  may be arranged on the upper surface of the name sheet  15 , instead of the bottom surface of the body sheet  12 . In this case, to improve the comfort of wearing, it is preferred that the projection  17  be formed of soft material exhibiting improved impact absorbing performance, such as foamed resin. 
     An adhesive agent may be applied to the bottom surface of the projection  17 , and a surface formed by the adhesive agent may be covered by a removable film. The projection  17  is used in a state bonded with footgear or an insole after the film is removed. 
     The body sheet  12  may be formed of artificial leather, vinyl chloride resin, or natural leather, instead of the fabric such as woven fabric, knitted fabric, and unwoven fabric. 
     The projection  17  may be formed of, instead of the synthetic resin, natural resin or its foamed body, synthetic or natural rubber or its foamed body, a woven or knitted or unwoven product of synthetic or natural fabric, artificial or natural leather, or cork. Alternatively, the projection  17  may be formed of metal such as gold, silver, copper, aluminum, steel, and stainless steel, ceramic, glass, natural infrared emitting stones, magnets, or artificial stones. 
     Although the illustrated embodiment is embodied as the shoe or the sock, the present invention may be applied to other types of footgear including the clogs, the slippers, the sandals, the high heels, and Japanese tabi socks. Alternatively, the present invention may be applied to insoles installed in these types of footgear. 
     The inner bottom of the footgear may be formed by a sheet of compressed pulp, a leather sheet, or an unwoven fabric. The projection  17  may be formed on a surface of the inner bottom. 
     Further, the bottom material of the footgear may be formed of rubber, leather, or synthetic resin. The projection  17  may be arranged on a surface of the bottom material.