Abstract:
A method of manufacturing an article of footwear includes providing an outsole and a midsole. The outsole and the midsole are secured together such that a bottom surface of a first midsole element overlaps and directly secures to an upper surface of a first outsole element to define a first element assembly, such that a bottom surface of a second midsole element overlaps and directly secures to an upper surface of a second outsole element to define a second element assembly, and such that an outsole groove and a midsole groove are substantially aligned and in communication with each other in the thickness direction of the outsole and the thickness direction of the midsole. Moreover, the method includes interlocking the first and second element assemblies with each other.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 12/365,583, filed on Feb. 4, 2009, now U.S. Pat. No. 8,215,037. The entire disclosure of the above application is incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to footwear and, more particularly, relates to an article of footwear with a plurality of interlocking midsole and outsole elements. 
     BACKGROUND 
     Articles of footwear usually include an upper, a midsole, and an outsole. The upper can include sections of thin material, straps, or the like for securing the footwear to the wearer&#39;s foot. The outsole is typically a unitary piece of relatively high-friction material that provides traction for the footwear. Also, the midsole can be a unitary piece of foam or other similar material disposed between the upper and the outsole for providing cushioned support for the wearer. 
     SUMMARY 
     A method of manufacturing an article of footwear is disclosed. The method includes providing an outsole and a midsole. The outsole including an outsole groove that extends generally in a thickness direction through the outsole to separate the outsole into first and second outsole elements. The first and second outsole elements each include a respective upper surface. The midsole includes a midsole groove that extends generally in a thickness direction through the midsole to separate the midsole into first and second midsole elements. The first and second midsole elements each include a respective bottom surface. The outsole and the midsole are secured together such that the bottom surface of the first midsole element overlaps and directly secures to the upper surface of the first outsole element to define a first element assembly, such that the bottom surface of the second midsole element overlaps and directly secures to the upper surface of the second outsole element to define a second element assembly, and such that the outsole groove and the midsole groove are substantially aligned and in communication with each other in the thickness direction of the outsole and the thickness direction of the midsole. Moreover, the method includes interlocking the first and second element assemblies with each other. 
     Additionally, a method of customizing an article of footwear is also disclosed. The method includes selecting an outsole including an outsole groove that extends generally in a thickness direction through the outsole to separate the outsole into first and second outsole elements. The first and second outsole elements each include a respective upper surface. The method also includes selecting a midsole including a midsole groove that extends generally in a thickness direction through the midsole to separate the midsole into first and second midsole elements. The first and second midsole elements each include a respective bottom surface. The midsole and the outsole are secured together such that the bottom surface of the first midsole element overlaps and directly secures to the upper surface of the first outsole element to define a first element assembly, such that the bottom surface of the second midsole element overlaps and directly secures to the upper surface of the second outsole element to define a second element assembly, such that the outsole groove and the midsole groove are substantially aligned and in communication with each other in the thickness direction of the outsole and the thickness direction of the midsole, and such that the first and second element assemblies interlock with each other. The first midsole element differs from the second midsole element by a different material, a different color, a different durometer, and/or a different resistance to resilient deformation. 
     Still further, a method of customizing an article of footwear is disclosed that includes selecting an outsole including an outsole groove that extends generally in a thickness direction through the outsole to separate the outsole into first and second outsole elements. The first and second outsole elements each include a respective upper surface. The method also includes selecting a midsole including a midsole groove that extends generally in a thickness direction through the midsole to separate the midsole into first and second midsole elements. The first and second midsole elements each include a respective bottom surface. The midsole and the outsole are secured together such that the bottom surface of the first midsole element overlaps and directly secures to the upper surface of the first outsole element to define a first element assembly, such that the bottom surface of the second midsole element overlaps and directly secures to the upper surface of the second outsole element to define a second element assembly, such that the outsole groove and the midsole groove are substantially aligned and in communication with each other in the thickness direction of the outsole and the thickness direction of the midsole, and such that the first and second element assemblies interlock with each other. The first outsole element differs from the second outsole element by a different coefficient of friction, a different material, a different thickness, and/or a different color. 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1A  is an isometric view of an exemplary embodiment of an article of footwear according to various teachings of the present disclosure; 
         FIG. 1B  is an exploded view of the article of footwear of  FIG. 1A ; 
         FIG. 2  is a bottom plan view of the article of footwear of  FIG. 1A ; 
         FIG. 3  is a sectional view of the article of footwear of  FIG. 1A ; and 
         FIG. 4  is an exemplary embodiment of a pressure map illustrating a pressure distribution for the article of footwear of  FIG. 1A . 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     Referring initially to  FIGS. 1A and 2 , an exemplary embodiment of an article of footwear  10  is illustrated according to various teachings of the present disclosure. For purposes of discussion, the footwear  10  will be discussed using a reference coordinate system X, Y, Z ( FIG. 1 ). 
     Generally, the article of footwear  10  includes an upper  12 , an outsole  14 , and a midsole  16 . As will be discussed, the midsole  16  is operably secured to both the upper  12  and the outsole  14 , and the midsole  16  is disposed between the upper  12  and the outsole  14 . The midsole  16  and the outsole  14  generally extend in transverse directions (i.e., within the X-Y plane) ( FIG. 1A ), and the midsole  16  and the outsole  14  each have a thickness defined along a thickness direction (i.e., along the Z-axis). 
     In some embodiments, the upper  12  includes various thin sections of material that partially overlap each other and that are operably secured to each other, for example, by stitching, adhesives, and the like. The upper  12  defines a cavity in which the wearer&#39;s foot is received. The upper  12  can also include a fastening structure, such as laces, buckles, and/or other features for tightly securing the upper  12  to the foot of the wearer. It will also be appreciated that the upper  12  can include various decorative features. In addition, the upper  12  can have any suitable shape and/or features that adapt the article of footwear  10  for its intended use. 
     As shown in  FIGS. 1A ,  1 B, and  2 , the outsole  14  can include a layer of material that extends in the transverse directions (i.e., within the X-Y plane). The outsole  14  can also have any suitable curvature along the transverse directions. Additionally, the outsole  14  can have any suitable thickness (i.e., along the Z-axis), and the thickness of the outsole  14  can vary in any suitable fashion. Moreover, the outsole  14  can include various grooves, projections or other features for increasing traction of the footwear  10 . 
     In addition, the outsole  14  includes a plurality of outsole grooves  18 . As shown in  FIG. 3 , the outsole grooves  18  extend entirely through the thickness of the outsole  14  (i.e., along the Z-axis); however, the outsole grooves  18  can extend only partially through the thickness of the outsole  14  in some embodiments. Also, the outsole grooves  18  extend in the transverse directions (i.e., within the X-Y plane) ( FIGS. 1A and 2 ). As such, the outsole grooves  18  separate the outsole  14  into a plurality of separate outsole elements  20   a - 20   t  ( FIG. 1B ). The outsole elements  20   a - 20   t  can have any suitable shape and size. In the embodiment shown, the outsole elements  20   a - 20   t  each have a plurality of generally planar sides  22  that extend in the thickness direction. The planar sides  22  of adjacent outsole elements  20   a - 20   t  face each other. In some embodiments, the outsole grooves  18  are wide enough in the transverse directions to space the outsole elements  20   a - 20   t  apart slightly (e.g., 1-2 millimeters). However, the grooves  18  can have a relatively small width, allowing the outsole elements  20   a - 20   t  to abut each other in some embodiments. As will be discussed, the outsole grooves  18  increase flexibility of the outsole  14  and can make the outsole  14  more versatile. 
     Furthermore, in some embodiments, the outsole grooves  18  are shaped such that the outsole elements  20   a - 20   t  interlock with each other. In the embodiment shown, the outsole elements  20   a - 20   t  are shaped in a fashion similar to interlocking jigsaw puzzle pieces ( FIG. 2 ). For instance, the outsole element  20   k  includes a projection  24  that projects from the respective planar side  22  ( FIG. 2 ). Moreover, an adjacent outsole element (e.g., element  20   j ) includes a recess  30  that recesses into the respective planar side  22 . The recess  30  receives the projection  24  to interlock elements  20   k  and  20   j.  As shown, the other outsole elements  20   a - 20   t  can also include respective interlocking pairs of projections  24  and recesses  30 . 
     The projections  24  and recesses  30  can have any suitable shape. For instance, in the embodiments shown, the projection  24  includes an enlarged head  26  and a neck portion  28 , which is narrower than the enlarged head  26 . The neck portion  28  is disposed between the head  26  and the respective planar side  22  of the outsole element  20   a - 20   t.  Furthermore, the recess  30  includes an enlarged portion  31  and a narrow portion  32 . The enlarged portion  31  of the recess  30  receives the enlarged head  26  of the projection  24  such that the narrow portion  32  of the recess  30  limits movement of the enlarged head  26  out of the enlarged portion  31  of the recess  30 . Accordingly, as will be discussed, the outsole elements  20   a - 20   t  can shift slightly relative to each other for added flexibility of the footwear  10 . However, the outsole elements  20   a - 20   t  interlock with each other to maintain sufficient union of the outsole  14 . 
     Furthermore, in some embodiments, the outsole  14  includes an outer periphery  34  that is entirely continuous ( FIGS. 1A ,  1 B,  2 ). More specifically, as shown in  FIG. 1B , the outsole elements  20   a,    20   d,    20   g,    20   j,    20   m ,  20   p,    20   s,    20   r,    20   o ,  20   l ,  20   i,    20   f,    20   c,  and  20   t  (“the peripheral outsole elements”) cooperate to define the outer periphery  34  of the outsole  14 . The remaining outsole elements  20   b,    20   e,    20   h,    20   k,    20   n,  and  20   q  (“the interior outsole elements”) are spaced apart from the outer periphery  34  of the outsole  14 . 
     The peripheral outsole elements  20   a,    20   d,    20   g,    20   j,    20   m,    20   p ,  20   s,    20   r,    20   o ,  20   l ,  20   i,    20   f,    20   c,  and  20   t  are each integrally coupled to adjacent ones of the peripheral outsole elements  20   a,    20   d,    20   g,    20   j,    20   m,    20   p,    20   s,    20   r ,  20   o ,  20   l ,  20   i,    20   f,    20   c,  and  20   t  such that the outer periphery  34  is entirely continuous. For instance, the outsole groove  18  separating outsole elements  20   f  and  20   i  ( FIG. 1B ) does not extend in the transverse direction to the outer periphery  34 , and elements  20   f  and  20   i  are integrally coupled to each other adjacent the outer periphery  34 . In some embodiments, the outsole groove  18  separating outsole elements  20   f  and  20   i  ( FIG. 1B ) tapers and terminates immediately adjacent the outer periphery  34  to maintain the continuous outer periphery  34  of the outsole  14 . Accordingly, because the outer periphery  34  is entirely continuous, the outsole  14  holds together to limit excessive relative movement of the outsole elements  20   a - 20   t.  In addition, the entirely continuous outer periphery  34  can aid in handling of the outsole  14 , for instance, during manufacture of the footwear  10 . 
     It will be appreciated that the outsole  14  can be made out of any suitable material. For instance, the outsole  14  can be made out of a high-friction polymeric material, such as rubber. Also, in some embodiments, the outsole  14  can be made out of a transparent material so that the midsole  16  is visible through the outsole  14 . Also, it will be appreciated that the outsole elements  20   a - 20   t  can vary in material, thickness, function, aesthetics, and the like. Accordingly, the outsole elements  20   a - 20   t  can be selected according to the respective transverse location of the outsole element  20   a - 20   t  on the footwear  10 , making the outsole  14  more versatile and adaptable as will be discussed in greater detail below. 
     Additionally, as shown in  FIGS. 1A ,  1 B, and  3 , the midsole  16  can include a layer of material that extends in the transverse directions (i.e., within the X-Y plane). The midsole  16  can also have any suitable curvature along the transverse directions. Furthermore, the midsole  16  can have any suitable thickness (i.e., along the Z-axis), and the thickness of the midsole  16  can vary in any suitable fashion. 
     In addition, the midsole  16  includes a plurality of midsole grooves  38  ( FIG. 1B and 3 ). As shown in  FIG. 3 , the midsole grooves  38  extend entirely through the thickness of the midsole  16  (i.e., along the Z-axis); however, the midsole grooves  38  can extend only partially through the thickness of the midsole  16  in some embodiments. Also, the midsole grooves  38  extend in the transverse directions (i.e., within the X-Y plane) ( FIG. 1B ). As such, the midsole grooves  38  separate the midsole  16  into a plurality of separate midsole elements  40   a - 40   t  ( FIG. 1B ). The midsole elements  40   a - 40   t  can have any suitable shape and size. In the embodiments shown, the midsole elements  40   a - 40   t  each have a plurality of generally planar sides  42  that extend in the thickness direction. The planar sides  42  of adjacent midsole elements  40   a - 40   t  face each other. In some embodiments, the midsole grooves  38  are wide enough in the transverse directions to space the midsole elements  40   a - 40   t  apart slightly (e.g., 1-2 millimeters). However, the grooves  38  can have a relatively small width, allowing the midsole elements  40   a - 40   t  to abut each other in some embodiments. As will be discussed, the midsole grooves  38  increase flexibility of the midsole  16  and can make the midsole  16  more versatile. 
     Furthermore, in some embodiments, the midsole grooves  38  are shaped such that the midsole elements  40   a - 40   t  interlock with each other. In the embodiment shown, the midsole elements  40   a - 40   t  are shaped in a fashion similar to interlocking jigsaw puzzle pieces ( FIG. 1B ). For instance, the midsole element  40   k  includes a projection  44  that projects from the respective planar side  42 . Moreover, an adjacent midsole element (e.g., element  40   j ) includes a recess  50  that recesses into the respective planar side  42 . The recess  50  receives the projection  44  to interlock elements  40   k  and  40   j.  As shown, the other midsole elements  40   a - 40   t  can also include respective interlocking pairs of projections  44  and recesses  50 . 
     The projections  44  and recesses  50  can have any suitable shape. For instance, in the embodiment shown in  FIG. 1B , the projection  44  includes an enlarged head  46  and a neck portion  48 , which is narrower than the enlarged head  46 . The neck portion  48  is disposed between the head  46  and the respective planar side  42  of the respective midsole element  40   a - 40   t . Furthermore, the recess  50  includes an enlarged portion  51  and a narrow portion  52 . The enlarged portion  51  of the recess  50  receives the enlarged head  46  of the projection  44  such that the narrow portion  52  of the recess  50  limits movement of the enlarged head  46  out of the enlarged portion  51  of the recess  50 . Accordingly, as will be discussed, the midsole elements  40   a - 40   t  can shift slightly relative to each other for added flexibility of the footwear  10 . However, the midsole elements  40   a - 40   t  interlock with each other to maintain sufficient union of the midsole  16 . 
     Furthermore, in some embodiments, the midsole  16  includes an outer periphery  54  that is entirely continuous ( FIGS. 1A and 1B ). More specifically, as shown in  FIG. 1B , the midsole elements  40   a,    40   d,    40   g,    40   j,    40   m ,  40   p,    40   s,    40   r,    40   o ,  40   l ,  40   i,    40   f,    40   c,  and  40   t  (“the peripheral midsole elements”) cooperate to define the outer periphery  54  of the midsole  16 . The remaining midsole elements  40   b,    40   e,    40   h,    40   k,    40   n,  and  40   q  (“the interior midsole elements”) are spaced apart from the outer periphery  54  of the midsole  16 . 
     The peripheral midsole elements  40   a,    40   d,    40   g,    40   j,    40   m,    40   p ,  40   s,    40   r,    40   o ,  40   l ,  40   i,    40   f,    40   c,  and  40   t  are each integrally coupled to adjacent ones of the peripheral midsole elements  40   a,    40   d,    40   g,    40   j,    40   m,    40   p,    40   s,    40   r ,  40   o ,  40   l ,  40   i,    40   f,    40   c,  and  40   t  such that the outer periphery  54  is entirely continuous. For instance, the midsole groove  38  separating midsole elements  40   f  and  40   i  ( FIG. 1B ) does not extend in the transverse direction to the outer periphery  54 , and elements  40   f  and  40   i  are integrally coupled to each other adjacent the outer periphery  54 . In some embodiments, the midsole groove  38  separating midsole elements  40   f  and  40   i  ( FIG. 1B ) tapers and terminates immediately adjacent the outer periphery  54  to maintain the continuous outer periphery  54  of the midsole  16 . Accordingly, because the outer periphery  54  is entirely continuous, the midsole  16  holds together to limit excessive relative movement of the midsole elements  40   a - 40   t.  In addition, the entirely continuous outer periphery  54  can aid in handling of the midsole  16 , for instance, during manufacture of the footwear  10 . 
     It will be appreciated that the midsole  16  can be made out of any suitable material. For instance, the midsole  16  can be made out of any suitable foam material, such as Ethylene Vinyl Acetate (EVA) foam and/or Thermoplastic Polyurethane (TPU). The midsole  16  can also include a material with air pockets or fluid-filled bladders included therein, such as materials disclosed in U.S. Pat. No. 7,386,946, issued Jun. 17, 2008 to Goodwin, U.S. Pat. No. 7,070,845, issued Jul. 4, 2006 to Thomas et al., and/or U.S. Patent Publication No. 2006/0230636, published Oct. 19, 2006 to Kokstis et al., each of which is incorporated herein by reference in its entirety. Also, it will be appreciated that the individual midsole elements  40   a - 40   t  can vary in material, thickness, function, aesthetics, and the like. Accordingly, the midsole elements  40   a - 40   t  can be selected according to the respective transverse location of the midsole element  40   a - 40   t  on the footwear  10 , making the midsole  16  more versatile and adaptable as will be discussed in greater detail below. 
     As shown in  FIGS. 1B and 3 , the outsole grooves  18  can be substantially aligned with the midsole grooves  38  so that the midsole and outsole grooves  38 ,  18  substantially overlap in plan view ( FIG. 2 ). Accordingly, the midsole and outsole grooves  38 ,  18  are in communication with each other in the thickness direction (i.e., along the Z-axis) as shown in  FIG. 3 . It will be appreciated, however, that the outsole grooves  18  can be misaligned with the midsole grooves  38  in some embodiments. Furthermore, it will be appreciated that the outsole  14  can be a continuous sheet of material while the midsole  16  includes the individual midsole elements  40   a - 40   t.  Likewise, it will be appreciated that the midsole  16  can be a continuous sheet of material while the outsole  14  can include the individual outsole elements  20   a - 20   t.    
     Furthermore, in the embodiment shown in  FIG. 3 , individual ones of the outsole elements  20   a - 20   t  are operably secured to corresponding ones of the midsole elements  40   a - 40   t.  Accordingly, each outsole element  20   a - 20   t  pairs with a respective midsole element  40   a - 40   t  to define an element assembly  60   a - 60   t  ( FIG. 3 ). In some embodiments shown in  FIG. 3 , an upper surface  52  of the outsole element  20   e  is fixed to a bottom surface  54  of the midsole element  40   e  such that the elements  20   e,    40   e  collectively define an element assembly  60   e.  It will be appreciated that the outsole elements  20   a - 20   t  can be operably secured to the respective midsole elements  40   a - 40   t  in any suitable fashion. In some embodiments, the outsole elements  20   a - 20   t  are fixed to corresponding ones of the midsole elements  40   a - 40   t,  such as by adhesive or other bonding. Also, in some embodiments, the outsole elements  20   a - 20   t  are removably coupled to corresponding ones of the midsole elements  40   a - 40   t.    
     Because the outsole elements  20   a - 20   t  and midsole elements  40   a - 40   t  are separate from other ones of the outsole elements  20   a - 20   t  and midsole elements  40   a - 40   t,  the footwear  10  can be adapted, adjusted, and customized in a variety of ways. For instance, different outsole elements  20   a - 20   t  varying in thickness, coefficient of friction, material, color, etc. can be interlocked and integrated in the footwear  10 . Likewise, different midsole elements  40   a - 40   t  varying in thickness, resistance to resilient deformation, material, color, etc. can be interlocked and integrated in the footwear  10 . 
     More specifically, as shown in  FIG. 3 , the thickness of the individual midsole elements  40   a - 40   t  can vary. More specifically, in the embodiments shown, the midsole element  40   b  has a thickness of t 1 , the midsole element  40   e  has a thickness t 2 , and the midsole element  40   k  has a thickness t 3 . As shown, the thickness t 1  of element  40   b  is greater than the thickness t 2  of element  40   e,  but the thickness t 1  of element  40   b  is less than the thickness t 3  of element  40   k.  Furthermore, the resistance to resilient deformation of the midsole elements  40   t,    40   b,    40   e,    40   h,    40   k,  and  40   n  can vary as shown in  FIG. 3 . For instance, element  40   t  can have a lower density, durometer, etc. than elements  40   b,    40   k,  and  40   n  (as represented by cross hatching in  FIG. 3 ), and element  40   h  can have a lower density, durometer, etc. than element  40   t.  As such, the elements  40   b,    40   k,  and  40   n  can provide higher resistance to resilient deformation than that of elements  40   t  and  40   h,  and element  40   h  can provide higher resistance to resilient deformation than element  40   t.    
       FIG. 4  illustrates a pressure “map” of the footwear  10  to represent the location of the highest and lowest pressure on the midsole  16  during use of the footwear  10 . For instance, loading can be highest near the center of the heel of the wearer. Thus, midsole element  40   b  can have a preselected thickness, durometer, material, or any other characteristic to handle the increased pressure loading. Other midsole elements  40   a,    40   c - 40   t  can be similarly selected. For instance, loads near the arch of the foot are relatively low, and thus, midsole element  40   e  can have a preselected thickness, durometer, material, or any other characteristic to handle the decreased pressure loading. Accordingly, the midsole  16  is very versatile. 
     The outsole elements  20   a - 20   t  can be preselected in a similar fashion. For instance, the individual outsole elements  20   a - 20   t  can be selected to provide higher friction in some areas of the outsole  14  as compared to other areas. Also, in the embodiment shown in  FIG. 3 , the thickness of each outsole element  20   a - 20   t  is such that the outsole elements  20   a - 20   t  are flush with each other on a side opposite from the midsole elements  40   a - 40   t;  however, it will be appreciated that the outsole elements  20   a - 20   t  can have any suitable thickness. 
     Manufacture of the footwear  10  can be accomplished in any suitable fashion. For instance, in some embodiments, the outsole elements  20   a - 20   t  are individually selected and assembled, and the individual midsole elements  40   a - 40   t  are individually selected and assembled in a similar fashion. Then, the outsole  14  is bonded to the midsole  16  (e.g., in a molding process), and the midsole  16  is bonded to the upper  12 . Alternatively, the outsole  14  can be removably secured to the midsole  16  and/or the midsole  16  can be removably secured to the upper  12 . 
     In another embodiment, the peripheral midsole elements  40   a ,  40   d,    40   g,    40   j,    40   m,    40   p,    40   s,    40   r,    40   o,    40   l ,  40   i,    40   f,    40   c,  and  40   t  are integrally coupled, leaving an opening for the remaining midsole elements  40   b,    40   e,    40   h ,  40   k,    40   n,  and  40   q.  The midsole elements  40   b,    40   e,    40   h,    40   k,    40   n,  and  40   q  are selected and arranged between the peripheral midsole elements  40   a,    40   d,    40   g ,  40   j,    40   m,    40   p,    40   s,    40   r,    40   o ,  40   l ,  40   i,    40   f,    40   c,  and  40   t.  The outsole elements  20   a - 20   t  of the outsole  14  are assembled in a similar fashion. Then, the midsole  16  is operably secured to the outsole  14 , and the upper  12  is operably secured. 
     In another embodiment, the outsole  14  and the midsole  16  are initially monolithic layers of material. The outsole  14  and midsole  16  are operably secured together, and then the outsole grooves  18  and the midsole grooves  38  are subsequently formed therein. For instance, a laser cutting process can be used to form the grooves  18 ,  38 . 
     It will be appreciated that the grooves  18 ,  38  increase the flexibility of the outsole  14  and the midsole  16 , and yet the continuous outer peripheries  34 ,  54  of the outsole  14  and the midsole  16  serve to hold the outsole  14  and the midsole  16  together for added durability and uniform flexion of the footwear  10 . Moreover, because the element assemblies  60   a - 60   t  interlock, the element assemblies  60   a - 60   t  can distribute loads to each other to improve performance of the footwear  10 . 
     Moreover, the footwear  10  can facilitate recycling. For instance, because of the outsole and midsole grooves  18 ,  38 , the element assemblies  60   a - 60   t  can be easily separated from each other for recycling purposes. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.