Abstract:
A correctional running shoe with an upper shoe attached to a negative sole having a heel, a specially designed flexible midsole, and a toe portion, all made from cushioned material. The heel has at least about 1/6 to about 1/3 less thickness than the toe portion so that the foot naturally rests with the toe inclined and the heel downward.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to the field of footwear, more particularly corrective running athletic shoes, designed to provide gait correction, proper shock absorption, and the ability to minimize running injuries. 
       BACKGROUND OF THE INVENTION 
       [0002]    Running, varying from everyday exercise running to cross country running, track season running and the like, is known to cause repetitive stress injuries, particularly for long distance runners. Injuries may vary from ligament stress, to muscle stress, to actual stress fractures. In fact, reports show that at least 60% of runners are nursing some sort of injury at any given time. 
         [0003]    It has been noticed that in European countries and the USA, most runners are heel strikers, that is they run heel to toe. In contrast, long distance barefoot runners from African nations are frequently forefoot strikers, that is to say they run toe to heel. It has been noticed that many of these African long distance runners, who actually prefer barefoot running (and who run as forefoot strikers) simply do not experience nearly the high level of repetitive stress injuries of heel striking runners. 
         [0004]    There is, however, great difficulty in converting runners from heel strikers to toe strikers. During the correctional period while the runner is attempting to change over to a primary forefoot striker, different muscles are used than normal and pain resulting therefrom usually results in abandonment of the project with the runner returning to the more common heel-strike-first method. Most, if not all current running shoes are designed for heel strikers. 
         [0005]    In the past, there have been some walking shoes that have so-called negative soles, that is to say, the sole is thicker at the toe than at the heel to encourage walking in perhaps a more healthful manner (see for example, U.S. D472,038 and U.S. Pat. No. 6,578,290). These shoes, however, sold under the trademark Earth® Shoes are not designed for athletic use, nor are they designed as a correctional shoe to encourage and enforce forefoot striking first running 
         [0006]    It is a primary objective of this invention to provide a correctional shoe that encourages a runner to land in the neighborhood of the tarsal-metatarsal joint, i.e., approximately at the base of the toes. The difference in the correctional shoe and shoes such as Earth® Shoes is that the correctional running shoe is more aggressively designed with the front of the shoe actually thicker than the heel and with specially designed flexible struts in the arch or midsole section, all to encourage the runner to touch down the toe first instead of the heel. 
         [0007]    Another primary objective of the invention is to provide a corrective shoe that is more effective than any before for converting a heel striker to a toe striker, all with less muscle stress and ligament stress during the corrective period. 
         [0008]    An even further objective of the present invention is to use force deflecting struts in the mid sole area or arch area of a running shoe in order to provide maximum flexibility in the mid sole area under the arch of the wearer&#39;s foot. 
         [0009]    This shoe therefore differs considerably from regular standard heel to toe drop on regular running shoes, which is usually ½″ making it difficult to hit the heel portion of the shoe first, and making it easier for runners who wear such a shoe and to convert themselves to the barefoot style of toe strike first. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention relates to a correctional shoe designed to force a toe/heel running gait. The shoe has a conventional upper but a negative sole having a heel portion, a midsole portion, and a toe portion, all made from cushioned sole material. The heel portion has about ⅙ to about ⅓ less thickness than the toe portion, and the mid sole portion has a force deflector strut or struts to provide a maximum, flexible mid sole arch area under the wearer&#39;s foot. The result is a shoe which can be comfortably worn during training of a runner to be a toe striker rather than a heel striker without the usual stress of joints, ligaments, and muscles from wearing conventional heel strike running shoes while trying to retrain to a toe striker. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a perspective view of a typical correctional shoe of the present invention. 
           [0012]      FIG. 2  is a drawing showing gait rest posture line of a person wearing the negative sole correctional shoe. 
           [0013]      FIG. 3  is a side view of the sole of the present invention. 
           [0014]      FIG. 4  is a bottom plan view of the sole of the present invention. 
           [0015]      FIG. 5  is a bottom perspective view of the sole with the incorporated midsole struts for maximum arch flexibility. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]    Referring to  FIG. 1 , it shows a side view of a shoe  10  of the present invention having an upper  12  and a cushioned sole  14 . The cushioned sole  14  is made of conventional running shoe cushioning materials. For example, the sole may include or be made from Ethyl Vinyl Acetate (EVA), some portions of it, such as an outer sole made from rubber. Suitable soles and sole constructions for use as sole  14  are illustrated in U.S. Pat. No. 6,026,593, which is incorporated herein by reference. This invention is not the polymeric cushion sole material, but the construction or design of it. 
         [0017]      FIG. 2  shows the sole  14  of the present shoe under the foot of a person  16  to show the effect on the posture line  18 . As can be seen, the sole  14  is a so-called negative sole, that is to say it is lower at the heel  20  than at the toe portion  22 . The result of this is a natural standing posture, as illustrated in  FIG. 2 . 
         [0018]      FIGS. 3 and 4  show respectively a side view of the sole only and in  FIG. 4 , a plan view of the sole only. As shown, the sole  14  has a negative tilt to it. The heel portion  20  can generally have a thickness of 20 mm to 30 mm, preferably 20 mm to 25 mm. The toe portion  22  of the correctional shoe  10  can generally have a thickness of from about 30 mm to 45 mm, preferably 30 mm to 35 mm. 
         [0019]    Importantly, in order to provide flexibility in the arch area at a maximum level, the midsole  24  has at least two struts, here three,  26 ,  28 , and  30  (three depicted) embedded in the midsole  24  and oriented along the long axis of the shoe  10 . 
         [0020]    The struts  26 ,  28 , and  30  can be rib-like structures, c-shaped from a side view, s-shaped from a side view, or smooth or wavy, as deemed most appropriate. Generally, this provides enhanced flexibility, i.e., the strut as seen from a side view has curvature providing a spring like action. 
         [0021]      FIG. 5  shows a bottom perspective view of the shoe and its sole with like parts similarly numbered. 
         [0022]    Some shoes may rather than use actual struts, currently available in the market, use impact air cushions in a similar manner to absorb shock and provided deflection and cushioning. These may be used in lieu of actual physical struts but serve the same purpose. As used herein, the term force deflection struts is defined to include impact air cushions, shock cushions, and as well struts springs or any other deflection enhancing material embedded in the arch area of the sole  14 , including an embedded different polymer material from the rest of the sole. 
         [0023]    When the shoe is placed on the human wearer&#39;s foot and the person stands as indicated at  16 , the posture line  18  is automatically assumed. When running, the person will find it almost impossible to do anything but running toe strike first. For anything else they must assume awkward positions and/or risk tumbling. The impact area under the arch (i.e., midsole portion) provides enhanced flexibility to cushion and shock, lessening the strain in retraining the body and naturally more spring in the foot and ankle area, and less heel impact shock. 
         [0024]    Like barefoot running, the corrective shoe encourages a fast cadence, focusing on lifting of your feet before landing, and a natural body bend to take advantage of the natural shock absorption of ankles, knees, and hips when the body is bent. Moreover, the muscles of the legs and calves are gradually corrected without the usual immediate soreness and pain caused by switch over from heel strike to toe strike. 
         [0025]    It therefore can be seen that the shoe accomplishes at least all of its stated objectives.