Patent Publication Number: US-2010115796-A1

Title: Heel construction for footwear

Description:
BACKGROUND OF THE INVENTION 
     An increase in the popularity of exercise, as well as everyday walking and standing, provides a need to alleviate and relieve stress on a person&#39;s feet and legs. It is important that shoes and other footwear provide adequate shock absorption and ability, as well as maneuverability. Conventional articles of footwear include an upper structure and a sole structure. The upper structure can form the portion of the footwear for receiving a foot. 
     A sole structure can include an insole, a midsole and an outsole. An insole is typically adjacent to the lower surface of the foot. A midsole forms the middle layer of the sole structure and can serve a variety of purposes, which may include controlling foot motions and attenuating ground reaction forces. An outsole forms a resistive surface that may come into contact with the ground. Outsoles have been developed to provide cushioning and stability to the foot of the wearer. In some cases, soles are articulated, as disclosed by U.S. Pat. No. 7,290,357, which is hereby incorporated by reference in its entirety. Such articulation has been provided in a direction to provide additional flexibility to a sole structure when used for running in a relatively straight line. 
     Therefore, a need exists for an improved article of footwear which can allow for improved cornering, maneuvering, or severe changes in direction. 
     SUMMARY OF THE INVENTION 
     The invention provides an article of footwear with an articulated heel portion. Various aspects of the invention described herein may be applied to any of the particular applications set forth below or for other types of footwear or shoes. The invention may be applied as a standalone system or method, or as part of an application, such as various articulation mechanisms or configurations. It shall be understood that different aspects of the invention can be appreciated individually, collectively, or in combination with each other. 
     In accordance with one aspect of the invention, the invention provides an athletic shoe for improved cornering performance, or to accommodate severe changes in direction, twisting, or maneuvering. The athletic shoe may include a heel portion with a defined longitudinal axis that is formed with at least one pair of substantially linear intersecting channels that facilitate articulation of the heel portion. Each intersecting channel may be oriented substantially non-parallel and non-perpendicular with respect to the longitudinal axis of the heel portion. The intersecting channels may form an X configuration. In some cases, the intersecting channels may have a diagonal orientation with respect to the longitudinal axis of the heel portion. 
     The channels may provide a degree of freedom to the heel portion while separating a plurality of articulated heel regions. The channels may enable one or more of the articulated heel regions to contact the ground while the shoe is being used for cornering or turning, and the rest of the shoe may be flexing or turning. The articulated heel regions may move harmoniously with the movement of the foot. A substantial portion of one or more articulated regions may contact the ground and prevent slip. 
     In some embodiments of the invention, additional parts of the shoes may include channels that provide flexibility, or other design features that may provide texture. The sole of a shoe may include one or more texturing features, such as ridges, that may provide added traction. Additionally, the sole of the shoe may include protrusions, such as cleats, which may also provide additional grip to the shoe to prevent sliding. In a preferable embodiment of the invention, the shoe may be an athletic shoe, such as a baseball cleat. In other embodiments, any of the features may be applied to any article of footwear. 
     Other goals and advantages of the invention will be further appreciated and understood when considered in conjunction with the following description and accompanying drawings. While the following description may contain specific details describing particular embodiments of the invention, this should not be construed as limitations to the scope of the invention but rather as an exemplification of preferable embodiments. For each aspect of the invention, many variations are possible as suggested herein that are known to those of ordinary skill in the art. A variety of changes and modifications can be made within the scope of the invention without departing from the spirit thereof. 
     INCORPORATION BY REFERENCE 
     All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which: 
         FIG. 1  shows a bottom view of an article of footwear with an X-shaped heel design. 
         FIG. 2  shows a bottom view of an article of footwear with an X-shaped heel design and additional elements. 
         FIG. 3  shows a bottom view of an article of footwear with an X-shaped heel design and cleats. 
         FIG. 4A  shows a side view of a sole design. 
         FIG. 4B  shows a bottom view of a sole design. 
         FIG. 4C  shows a side view of a sole design. 
         FIG. 5  shows how an article of footwear can behave during cornering. 
         FIG. 6  shows an article of footwear with an articulated heel. 
         FIG. 7  shows how cornering can be improved using an article of footwear with X-shaped articulated heel. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While preferable embodiments of the invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. 
     The following discussion and accompanying figures disclose an article of footwear in accordance with various aspects of the present invention. The footwear discussed and shown below may have a configuration that is suitable for athletic activities, particularly cornering. The concepts disclosed with respect to footwear may, however, be applied to footwear styles that are specifically designed for a wide range of various athletic activities, including basketball, baseball, football, soccer, golf, running, walking, and hiking, for example, and may also be applied to various non-athletic footwear styles. Accordingly, one skilled in the relevant art will recognize that the concepts disclosed herein may be applied to a wide range of footwear styles and are not limited to the specific embodiments discussed below and depicted in the figures. 
       FIG. 1  shows a bottom view of an article of footwear with an X-shaped heel design in accordance with one aspect of the invention. The outline of the bottom of the footwear is provided by way of example only, and any shape or configuration for a bottom of an article of footwear may be applied with the heel design. Furthermore, the heel design may be applied to any article of footwear or shoe. 
     The X-shaped heel design may provide an articulated heel. The articulation of the heel may be provided by a plurality of channels  10   a ,  10   b  or grooves in the heel surface. The channels may be intersecting to provide an X. In a preferable embodiment of the invention, two channels may intersect to form an X-shaped articulation for the heel. In other embodiments of the invention, multiple channels may intersect with one another to form one or more crosses where the channels may intersect. In some cases, the channels may be substantially linear. In other cases, the channels may curve, bend, or have any other sort of configuration or combination of configurations. 
     A heel portion of an article of footwear may have a defined longitudinal axis that may be oriented along the length of the footwear. At least one pair of intersecting channels may be oriented such that each intersecting channel is oriented substantially non-parallel and non-perpendicular with respect to the longitudinal axis of the heel portion. The pair of intersecting channels oriented in such a manner may be substantially linear. An articulation provided by such channels  10   a ,  10   b  may form an X as oriented with respect to the longitudinal axis. 
     Intersecting channels may intersect one another at any angle. In some cases, the intersecting channels may be perpendicular to one another, such that the opposing angles are 90 degrees. In other cases, the intersecting channels cross at an intersection formed with opposing angles that are not equal to 90 degrees. In some embodiments, the opposing angles formed on a medial or lateral side, with respect to the heel portion, of the intersecting channels may be greater than the angles formed on a rear or front side. In a preferable embodiment of the invention, intersecting angles may cross to form a 30 to 90 degree angle. 
     In some embodiments, additional intersecting channels may be provided that may also be oriented substantially non-parallel and non-perpendicular with respect to the longitudinal axis, while in alternate cases, only one or more pair of intersecting channels are oriented substantially non-parallel and non-perpendicular with respect to the longitudinal axis while one or more pair intersecting channels are oriented such that a channel may be parallel or perpendicular with respect to the longitudinal axis. 
     Any number of channels may intersect at a common point, in accordance with an alternate embodiment of the invention. For instance, two, three, four, six, eight, or ten channels may intersect at a common intersection. Such channels may be oriented such that they are evenly spaced apart, or may be oriented in an uneven manner. In some embodiments, channels may intersect at a middle portion, e.g., two channels intersecting to form an X. In some other embodiments, channels may intersect at an endpoint, rather than in a middle portion of the channel. For example, three channels may intersect at their endpoint to form a Y configuration. 
     The channels may have various sizes, lengths, thicknesses, depths, or profile shapes. For example, in a preferable embodiment, the channels may be about 6 to 25 mm thick. In some cases, the channels may have an extremely small thickness, comparable to forming a slit in the heel portion. In one embodiment, the intersecting channels may have the same thicknesses. The thicknesses of channels may vary such that one or more channels may have different thicknesses, or that the thicknesses of a channel may vary along its length. 
     In some cases, channels may range from about 40 to 120 mm in length, although the lengths of the channels may vary. The lengths of a plurality of channels may be substantially the same, or may vary. Similarly, channels may have depths that can fall into a preferable range of 4 to 15 mm in depth, although the channels may have any depth. In one embodiment, the depths of the channels may be the same. The depth of the channels may vary such that one or more channel may have different depths, or that the depth of a channel may vary along its length. In some embodiments, the depths of the channels may decrease where the channels intersect, such that the channels are more shallow at the center part of an X. In some cases, the variance of the depth of the channels may occur gradually or abruptly. 
     Channels may have any profile shape, including, but not limited to, rectangular channels, circular or rounded channels, triangular channels, trapezoidal channels, or extremely narrow channels, like slits in a sole. The various profile shapes may alter as the article of footwear flexes in use. A profile shape may remain the same or may vary along the length of the channel. 
     Each channel may provide a degree of freedom to the heel portion of the shoe. A channel may provide a degree of freedom in a direction perpendicular to the orientation of the channel. A channel may allow for articulation of the heel portion along the channel, which may provide flexibility to the heel portion. The articulation may occur upon impact during running, walking, cornering, or twisting. 
       FIG. 2  shows a bottom view of a shoe with an X-shaped heel design and additional elements in accordance with one embodiment of the invention. As discussed previously, the outline of the shoe bottom is provided by way of example only, and any shape or configuration for a shoe bottom may be applied with the design for the bottom of the shoe. Furthermore, the shoe bottom design may be applied to any shoe or article of footwear. 
     A shoe may include a sole structure. A sole structure may have a structure that can cooperatively articulate, flex, stretch, or otherwise move when an individual walks, runs, turns, pivots, or corners. That is, a sole structure can be configured to complement the natural motion of the foot during running, walking, cornering or other activities. In contrast with barefoot running, however, a sole structure may attenuate ground reaction forces to decrease the overall stress upon the foot. In some alternate embodiments, a sole structure may have a relatively stiff or inflexible construction that inhibits the natural motion of the foot. 
     For purposes of reference, a shoe may be divided into three general regions: a forefoot region  20 , a midfoot region  21 , and a heel region  22 . Such regions may not be intended to demarcate precise areas of footwear. Rather, the regions can represent general areas of footwear that provide a frame of reference during the following discussion. Although the regions apply generally to footwear, references to regions may also apply specifically the sole structure. 
     A shoe sole structure may include an insole, a midsole, and/or an outsole. An insole may be positioned adjacent to a lower surface of the foot and may enhance the comfort of footwear. A midsole may be secured to a lower portion of upper portion of a shoe and may be positioned to extend under the foot during use. A midsole may attenuate ground reaction forces when walking, running, or cornering. A midsole may be made of any materials known in the art, which may include, but are not limited to any of the conventional polymer foams that are utilized in footwear midsoles, including ethylvinylacetate and polyurethane foam. A midsole may also be formed from a relatively lightweight polyurethane foam. An outsole may be secured to a lower surface of midsole to provide wear-resistance, and/or may be recessed within a midsole. Suitable materials for an outsole may include, but are not limited to, any of the conventional rubber materials that are utilized in footwear outsoles, such as carbon black rubber compound. 
     A sole structure may have an articulated structure that may impart relatively high flexibility and articulation. The articulation may be provided by a midsole and/or outsole of a sole structure. The articulation may defined by grooves in a midsole and/or outsole. 
     A heel region of a sole structure can include one or more heel surface elements  23   a ,  23   b ,  23   c . A heel surface element may be configured to come into contact with the ground when the shoe is worn. Heel surface elements may be spaced between or separated by grooves  24   a ,  24   b . In some embodiments, the grooves separating the heel surface elements may be shallow, such that heel surface elements may only be defined on an outsole. In other embodiments, the grooves separating the heel surface elements may be deeper, such that heel surface elements, may also be defined as part of a midsole. In some cases, the grooves separating the heel surface elements may be so deep that heel surface elements may be defined by the entirety of the midsole, such that midsole and/or outsole may be divided into separate elements. The thickness of portion of the sole structure including grooves may vary along the longitudinal length of the sole structure, or along the lateral or medial sides of the sole structure. 
     In one example, a heel region may include a plurality of heel surface elements spaced between or separated by a plurality of substantially linear non-parallel grooves wherein the grooves are not formed laterally between a medial side and lateral side of the heel region. The grooves may not be oriented laterally, but may have any other orientation. In some embodiments, the grooves may be substantially linear. In a preferable embodiment, the grooves  24   a ,  24   b  may intersect at the heel region to form a cross-shape. The cross-shape may have any orientation, including one such that an X is formed with respect to a longitudinal axis defined by the length of the sole. The grooves may have any orientation that may allow heel surface elements of the shoe to aid in cornering. 
     In some embodiments, the grooves may be contained within the heel region. For example, the grooves may start and end within the heel region of a sole structure. In other examples, the grooves may extend to the ends of the heel region, all the way to an outer heel boundary. Or in another case, a groove may extend past a heel region into a midfoot region, and cross a midfoot boundary. 
     In a preferable embodiment, a heel region may include at least three heel surface elements  23   a ,  23   b ,  23   c  that may be separated by a pair of intersecting grooves  24   a ,  24   b . The grooves may enable the heel surface elements to move relative to one another. For example, a sole may bend at its heel region along a groove, which may enable heel surface elements on either side of the groove to move relative to one another. The grooves may form flexion lines in the sole structure, and may have an effect upon the directions of flex in the sole. The sole structure may flex or articulate in various manners as a result of the grooves. The heel surface elements may move harmoniously with the movement of a foot, such as when the wearer of the shoe is cornering or making a sharp turn. 
     The heel surface elements may have any shape, as defined by grooves separating the heel surface elements. For example, heel surface elements may have a roughly triangular configuration, wherein a triangle may have a curved edge, similar to a pie slice. Heel surface elements may also have quadrilateral shapes, such as rectangular or trapezoidal shapes, or may have curved shapes. Any number of heel surface elements may be provided, including, but not limited to, 1, 2, 3, 4, 6, 8, 12, or 20 heel surface elements. 
     A heel surface element may be defined by an outsole, a midsole, or a combination thereof. A heel surface element may include an outsole portion with ridges  25   a ,  25   b ,  25   c  that may provide texture to the heel surface element. In one embodiment, such ridges may take the form of concentric or annular rings. The concentric or annular rings may have a shape that may conform to the shape of the heel surface element. For instance, if a heel surface element has a roughly triangular shape, the ridges may have a roughly triangular shape as well. The ridges may or may not have a more curved configuration than the heel surface element. 
     In other embodiments, the ridges may have any configuration to provide texturing to a heel surface element. For example, the ridges may form zig-zagging patterns, honeycomb structures, geometric shapes, curved lines, or parallel lines. Similarly, other texturing features may be used, including but not limited to bumps, holes, spikes, or various protrusions. Any features may be provided to increase traction of a heel element. 
     A forefoot region of a sole structure may include a design that may provide additional flexibility to the forefoot region. A design  26  may curve across a forefoot region substantially laterally. For example, a forefoot region may have a groove going across substantially laterally. The groove may be curved. Such a groove may permit upward flexing of a sole structure, which may provide further traction during a running a cycle. In some cases, a groove may be used to provide articulation to a forefoot region. 
     The design may define a frontal forefoot region  27 . The frontal forefoot region may include one or more additional designs  28 , such as grooves. For instance, a frontal forefoot region may have a curved groove that may intersect with the lateral groove that may define a medial toe region  29   a  and a lateral toe region  29   b . Such a groove may provide lateral flexibility to the sole. 
     Such grooves may have similar or different characteristics to the grooves that define the heel surface elements. In some embodiments the grooves in the forefoot region may be wider and shallower than the grooves in the heel region. 
     In some embodiments, the designs in the forefoot region, may not be grooves, but may be other surface features. Such surface features may or may not provide flexibility to the forefoot region. In some embodiments, the surface features may be used to provide a form of traction to the forefoot region. For example, the surface features may include ridges of various patterns. The surface features may also be used to define regions of a sole, which may or may not have different thicknesses, materials, or features included. 
       FIG. 3  shows a bottom view of an article of footwear with an X-shaped heel design and cleats. In preferable embodiments of the invention, the article of footwear may be an athletic shoe. For instance, the athletic shoe may be designed to aid in cornering, twisting, or severe changes in direction. The athletic shoe may be a baseball cleat, soccer cleat, or other shoe that incorporates cleats. 
     For instance, an article of footwear may include a sole structure comprising one or more surface elements. For example, a heel region  30  of the footwear may comprise three surface elements  31   a ,  31   b ,  31   c  and a forefoot region  32  of the footwear may comprise two surface elements  33   a ,  33   b , while a midfoot region  34  of the footwear may comprise one surface element  35 . A surface of a sole may include one or more protrusions  36   a - 36   g , such as cleats. In some embodiments, a surface element may include one or more protrusions. In some embodiments, some surface elements may include no protrusions, while other surface elements may include one or more protrusions. 
     The protrusions may all be of the same length, or may have different lengths. Some of the protrusions may be more recessed than others. The protrusions may also have various shapes or orientations. 
     In a preferable embodiment of the invention, surface elements of a heel region of a footwear may each include one cleat. Surface elements of a frontal forefoot region of a foot may also each include one cleat. A midfoot surface element may include two cleats. Cleats may be placed to provide desired stability and gripping. Any number or arrangement of cleats may be provided. 
     The cleats may be formed of any material known in the art, which may include, but are not limited to, rubber, plastic, metal, which may or may not be the same material used to form a surface or a portion of the surface of a surface element. 
     The surface elements of a heel region may move relative to one another. Such movements may cause the relative orientation or positions of protrusions to change relative to one another. For example, when an athletic shoe is sued for cornering, the majority of the weight may be distributed to one or two heel elements. Any protrusions on the one or two heel elements may grip the ground while other protrusions on other heel elements may move relative to the gripping protrusions as the shoe may flex or twist. 
       FIG. 4A  shows a side view of a sole design from a lateral side in accordance with one embodiment of the invention. A midsole may include an upper surface  40  that may connect the midsole to an upper portion of a shoe. The upper surface may be positioned adjacent to the upper portion of the shoe and may be secured directly to upper, thereby providing support for the foot. The upper surface of the midsole may be contoured to conform to the natural, anatomical shape of a foot. 
     In some embodiments, the area of an upper surface of the midsole that is positioned in heel  41   a  region may have a greater elevation than the area of upper surface in forefoot region  41   b . In other words, a sole may be thicker at a heel region than at a forefoot region. In addition, an upper surface may form an arch support area in a midfoot region. Peripheral areas of upper surface may be generally raised to provide a depression for receiving and seating the foot. In alternate embodiments, an upper surface may have a non-contoured configuration. 
     A lower surface  42  of a sole structure may be configured to come into contact with the ground. The lower surface may be contoured as well. For instance, a portion of a lower sole structure at the midfoot region  43   a  may be slightly elevated or curved along the arch of the foot. Indentations  43   b  may also be provided along a lower surface of a sole structure, which may provide traction or flexibility. 
     Areas of the sole that exhibit a relatively thin thickness will, in general, possess more flexibility than areas of the sole that exhibit a greater thickness. Variations in the thickness of the sole may, therefore, be utilized to modify the flexibility of sole structure in specific areas. For example, a forefoot region may be configured to have relatively high flexibility by forming a lateral design feature with a lesser thickness. A relatively low flexibility may be imparted to a midfoot region by forming a sole with a greater thickness to provide support. Similarly, an intermediate flexibility may be imparted to a heel region by forming a sole with a thickness that is between the thicknesses of the forefoot region and the midfoot region. Alternatively, an intermediate flexibility may be imparted to a heel region even if the sole has a greater thickness than the midfoot region by providing channels that may provide an articulated heel. As such, variations in the thickness of the sole may be utilized in conjunction with articulation to provide desired flexibility and support for various parts of the shoe sole. 
     Portions of the shoe sole may have locally thicker outsole features  44   a - 44   d . Such outsole features may be pad-like features that provide a local bump from along the lower surface of the sole. Such outsole features may or may not be made of the same material as the rest of the sole. In some instances, the outsole features may be made of a more flexible or elastic materials. For one or more of the outsole features, a protrusion  45   a - 45   d , such as a cleat, may be provided. Additional protrusions  46 , or cleats may be provided along the lower surface of the sole structure. 
       FIG. 4B  shows a bottom view of a sole design in accordance with one embodiment of the invention. The sole design may include a heel region  47  which may be defined by an outer heel boundary  48   a  and a midfoot boundary  48   b . The heel region may have a longitudinal axis, which may be provided along the length of the sole. The heel region may be formed with articulated segments  49   a ,  49   b ,  49   c  between the outer heel and midfoot boundaries of the heel region. 
     In some embodiments, the articulated segments may provide the heel region with at least two angles of articulation. At least two angles of articulation may be substantially non-parallel and non-perpendicular with respect to the longitudinal axis of the heel region. For instance, one angle of articulation may have a diagonal orientation with respect to the longitudinal axis, while another angle of articulation may have another diagonal orientation, that is substantially the mirror image of the first diagonal orientation with respect to the longitudinal axis. A first articulated segment may include a back heel surface  49   b  as well as a lateral heel surface  49   a , while a second articulated segment may include a back heel surface  49   b  as well as a medial heel surface  49   c.    
     Any number or orientation of articulated segments may be provided, as defined by angles of articulation defined by the sole structure. 
     A bottom surface of a sole may provide texturing elements, which may provide traction to the bottom of the footwear. The texturing elements may include features, such as bumps, ridges, lines, holes, protrusions, or any combination thereof. Different regions of a sole may include different texturing features. For example, a heel surface region may include concentric ridges  401  on a heel pad that may protrude from the sole, along with a cleat  402  at the center of the concentric ridges. A medial forefoot region  403  may include a toe pad that may protrude from the sole, along with a cleat at the center of the pad  404 . A lateral forefoot region  405  may have a comb-like texture and may include one or more protrusions of varying shapes and sizes  406   a ,  406   b ,  406   c . A midfoot region may include various protrusions  407   a - 407   e  or pads  408   a ,  408   b . A logo  409  may be incorporated into the bottom of the sole, such as a midfoot region. 
       FIG. 4C  shows a side view of a sole design from a medial side in accordance with one embodiment of the invention. In some implementations, the lateral and medial sides of a sole may be substantially similar. In other implementations, the lateral and medial sides may be different. For example, one side may be more reinforced than another due to the weight distribution of the foot during a common use of the shoe. In some implementations, a lateral or medial side may be thicker and/or may provide greater elevation to one side of the foot. In some embodiments, a lateral or medial side may be have greater flexibility, or may be more cushioned. Additionally, a lateral or medial side may be designed to be more durable or to withstand more fatigue. 
       FIG. 5  shows how an article of footwear can behave during cornering and/or a severe turn in accordance with one aspect of the invention. In addition to a sole structure, an article of footwear can include an upper section  50   a ,  50   b . The upper section may form the portion of footwear for receiving the foot. For example, an upper section may be formed from various material elements that can be stitched or adhesively-bonded together to form an interior void that may comfortably receive a foot and secure the position of the foot relative to the sole structure  51   a ,  51   b . Other examples of upper sections may be provided by upper sections for cleats, other athletic shoes, or any form of footwear known in the art. The sole structure may be secured to a lower portion of upper section and may provide a durable, wear-resistant component for attenuating ground reaction forces as the footwear impacts the ground. 
     The sole may include one or more channels that may define articulated regions of the sole  52   a - 52   f.  The positions and orientations of the channels may be selected to complement the natural motion of the foot during the running cycle and/or cornering. In general, the motion of the foot during cornering proceeds as follows: Initially, the heel may strike the ground, followed by the ball of the foot. The heel may strike the ground unevenly, depending on the direction of cornering. As the heel leaves the ground, the foot may roll forward so that the toes make contact, and finally the entire foot leaves the ground to begin another cycle. 
     During the time that the foot is in contact with the ground, the foot may be angled to allow for cornering. For example, if a runner is cornering to the left much of the runner&#39;s weight may be distributed to the left side of the shoe. For a left shoe, that would mean more weight would be distributed to the lateral (outer) side of the shoe, for a right shoe, that would mean more weight would be distributed to the medial (inner) side of the shoe. 
     Articulated regions may improve cornering. For example, articulated regions may be provided on a heel such that there may be a hind articulated region, a lateral articulated region, and a medial articulated region. The articulated regions may enable much of the weight to be distributed to two of the articulated regions during cornering. For example, if a runner is making a sharp turn to the left, while the heel is striking the ground during a running cycle, the left shoe may have more weight on a hind articulated region  52   e  and a lateral articulated region  52   f.  The right shoe may have more weight on a hind articulated region  52   b  and a medial articulated region  52   c.  The articulation may allow the heel to flex such that the specified articulated regions are substantially parallel to the ground, or such that the specified articulated regions have increased contact with the ground to increase friction and decrease sliding. 
     The channels defining the articulated regions may have be intersecting to provide an X configuration on the heel. The angles of the channels forming the X may be determined to optimize or regulate toward an optimum cornering configuration. For example, if a runner is pivoting or making a sharp turn to the right, the heel of the sole may flex along a channel that allows articulated regions to the rear and to the left of the channel (when viewed from below the sole) to have increased ground contact. 
       FIG. 6  shows a shoe with an articulated heel in accordance with one aspect of the invention. The shoe can include a hindfoot region  63  comprising at least one pair of intersecting channels  60   a ,  60   b  that provide at least two hinged or pivotal sections, such as an inner section  61   a ,  61   b  and an outer section  61   b ,  61   c . The intersecting channels may be substantially linear and may have any orientation. For instance, the intersecting channels may be oriented such that neither of them are substantially parallel or substantially perpendicular to a lateral axis of the shoe. Such intersecting channels  60   a ,  60   b  may be oriented substantially diagonally with respect to the lateral axis of the article of footwear. 
     The hinged or pivotal sections may allow the negotiating of sharp turns. The hinged or pivotal sections may allow a surface of the various sections to remain in contact with a ground while the rest of the shoe may have some degree of freedom. For instance, when negotiating a left turn, an inner section  61   a ,  61   b  may be in firm contact with the ground, while the rest of the shoe may flex upwards or downwards, may roll from side to side, or may pivot about the inner section from right to left. This may allow a shoe to remain firmly in place without slipping, while providing the flexibility to allow rapid cornering. 
     A hindfoot region may include a plurality of cleats  62   a,    62   b,    62   c.  For instance, an inner section  61   a ,  61   b  and an outer section  61   b ,  61   c  can include one or more cleats. In some instances, various sections  61   a ,  61   b ,  61   c  of the hindfoot region may each include one cleat. The cleats may be oriented or placed on the sections as desired. The cleats may assist with keeping sections of the shoes firmly in place and to prevent slipping during cornering, twisting, sharp turns, or other forms of maneuvering. 
     The shoe may also include a forefoot region  64 . The forefoot region may also include one or more cleats  62   d,    62   e,    62   f . The forefoot region may also include any various protrusions  65 . Such protrusions or cleats may assist with keeping a section of the shoe firmly in place while the forefoot region is in contact with the ground during a running cycle. 
       FIG. 7  shows how cornering can be improved using an article of footwear with X-shaped articulated heel. Without an articulated heel, as described herein, a runner may follow an outer path  70  provided around the bases. However, with an articulated heel, a runner may be able to negotiate a sharper turn, and thereby, follow the inner path  71  provided around the bases, thereby saving time and improving performance in a baseball game. In preferable embodiments of the invention, the X-shaped articulated heel may be applied to a baseball cleat for improved pivoting and turning around the bases. This may enable a runner to situate one&#39;s foot in a position to round basis quicker and with less fatigue on the runner. In some alternate embodiments of the invention, a baseball cleat may be reinforced to provide greater support or greater durability for when a runner turns left, in anticipation of increased wear from running the bases. 
     The articulated heel may be applied to any other athletic shoe. For example, such cornering performance may be beneficial in sports such as soccer, football, rugby, lacrosse, or field hockey. Articulated heels may be applied to other athletic shoes, such as running shoes, hiking shoes, walking shoes, tennis shoes, basketball shoes, or golf shoes. Similarly, articulated heels may be useful for certain types of dance shoes. The articulated heel may be applied to any article of footwear. 
     It should be understood from the foregoing that, while particular implementations have been illustrated and described, various modifications can be made thereto and are contemplated herein. It is also not intended that the invention be limited by the specific examples provided within the specification. While the invention has been described with reference to the aforementioned specification, the descriptions and illustrations of the preferable embodiments herein are not meant to be construed in a limiting sense. Furthermore, it shall be understood that all aspects of the invention are not limited to the specific depictions, configurations or relative proportions set forth herein which depend upon a variety of conditions and variables. Various modifications in form and detail of the embodiments of the invention will be apparent to a person skilled in the art. It is therefore contemplated that the invention shall also cover any such modifications, variations and equivalents.