140 when viewing heel portion 140 from the rear. Upper portion 224 may be connected to the top of lower portion 222 and positioned diagonally toward medial side 104 of upper 102, creating an asymmetrical heel seam 220. Upper portion 224 may be positioned diagonally toward medial side 104 of upper 102 connecting medial side 104 and lateral side 106 of upper 102 between lower portion 222 and topline 154.

As shown in FIG. 2, the diagonal angle, e.g., medial bias, of upper portion 224 may allow upper portion 224 and to meet topline 154 between the medial malleolus bone and Achilles tendon of the foot of the wearer. For example, FIG. 2 includes a vertical axis, horizontally centered at heel portion 140. The diagonal angle of the medial bias, or offset from the vertical axis, may range from 10-45° toward medial side 104. The design of article 100 may have a thick outer collar lining 156. In some embodiments, upper portion 224 of heel seam 220 may extend through outer collar lining 156 to meet topline 154. Additionally, in some embodiments, the angle of upper portion 224 may dependent on the collar hang of collar portion 150, such that upper portion 224 of heel seam 220 may meet topline 154 and/or outer collar lining 156 between the medial malleolus bone and the Achilles tendon of the wearer. In some example embodiments, the angle may range depending on the wearer and each foot of the wearer, such that the bias of heel seam 220 may be customizable to the individual wearer. In some example embodiments, heel seam 220 may have a lateral bias. Upper portion 224 may have a diagonal offset from the vertical axis shown in FIG. 2, toward lateral side 106 of upper 102.

In some example embodiments, upper portion 224 of asymmetric heel seam 220 may have a lateral bias, as depicted in FIG. 3B. The lateral bias of upper portion 224 may contour the lateral side of the foot of the wearer. As described with reference to FIG. 3A, lower portion 222 may be connected to or adjacent to midsole 132 and may be horizontally centered on heel portion 140. Upper portion 224 may be connected to lower portion 222 and have a lateral bias. Upper portion 224 may be positioned diagonally toward lateral side 106.

While described separately as lower portion 222 and upper portion 224, heel seam 220 may be a single piece of material that is stitched or glued to upper 102 to join medial side 104 and lateral side 106. Lower portion 222 and upper portion 224 may transition from symmetrical to asymmetrical with curved edges, as shown in FIG. 2, or sharp edges. In some example embodiments, heel seam 220 may include aesthetic features, such as design, logos, and/or color.

As shown in FIGS. 3A and 3B, asymmetric heel seam 220 may be positioned to contour the foot of the wearer. Conventional athletic shoes, such as soccer shoes, may include heel seams that are vertically aligned with the center of the back of the shoe, e.g., a symmetric heel seam with equal parts on the medial and lateral sides of the heel. This position of the heel seam may cause friction and discomfort for the wearer. A tighter fitting shoe may cause increased friction and discomfort in the heel and ankle of the wearer. However, as discussed throughout a tighter fitting shoe may be preferable for the wearer during athletic events, particularly in events such as soccer, where the wearer's shoe may be in contact with the ball, ground, other people, and therefore likely to be accidentally removed.

Asymmetrical heel seam 220 may contour the wearer's foot to create a tighter fit while avoiding the increased friction and discomfort. For example, the diagonal position of upper portion 224 connects to collar portion 150 in the gap between medial malleolus bone and Achilles tendon of the wearer's foot. With this arrangement, the asymmetrical bias to medial side 104 preferably provides a better fit that contributes to the finesse capabilities of a wearer of article 100. In an example embodiments, upper portion 224 may have a lateral bias, and connected to collar portion 150 on the lateral side of the foot of the wearer. The lateral bias of upper portion 224 may connect to collar portion 150 between the lateral malleolus bone and the Achilles tendon of the foot of the wearer.

FIGS. 4A and 4B illustrate isometric views of asymmetric heel seam 220. Particularly, FIGS. 4A and 4B show the asymmetry of heel seam 220 on between medial side 104 and lateral side 106 of upper 102. Upper portion 224 of heel seam 220 does not align with the Achilles tendon on the back of the wearer's foot to avoid irritation during various athletic maneuvers. Upper portion 224 of heel seam 220 connects with topline 154 between the medial malleolus bone and Achilles tendon to prevent irritation to both parts of the ankle and foot. Additionally, the asymmetrical bias of upper portion 224 toward medial side 104 may allow the shoe to fit tighter in heel portion 140. This may provide the wearer with a more securely fitting shoe that also reduces irritation to the foot of the wearer.

In some example embodiments, topline 154 may have a medial topline edge 157 and lateral topline edge 158. Topline 154 may extend around opening 103 of article 100. In some embodiments, inner collar lining 152 and outer collar lining 156 may meet at topline 154. Topline 154 may be asymmetrical to correspond to heel seam 220. As shown in FIGS. 2-3 and 4A, lateral topline edge 158 may have consistent thickness on lateral side 106 of heel portion 140. Medial topline edge 157 may have varied thickness on medial side 104 to accommodate the asymmetrical bias of upper portion 224 toward medial side 104. For example, medial topline edge 157 may have the same thickness as lateral topline edge 158 at the horizontal center of heel portion 140. As medial topline edge 157 extends toward medial side 104, medial topline edge 157 may be thicker or thinner than lateral topline edge 158. The varied thickness of medial topline edge 157 may allow the heel portion 140 and/or collar portion 150 to contour the foot of the wearer. In some example embodiments, topline 154 may have consistent thickness on both medial side 104 and lateral side 106 of heel portion 140.

In some example embodiments, heel seam 220 may not be visible. As shown, in FIG. 5, overlay 510 may cover heel seam 220. However, heel seam 220 may still have an asymmetrical bias toward medial side 104, even though it is not visible. As discussed above, upper 102 may include an arrangement of layers. The layers of upper 102 may each be joined using heel seam 220, with an asymmetrical bias toward medial side 104. Heel seam 220 having an asymmetrical bias toward medial side 104 at each layer of upper 102 may prevent irritation for the wearer as none of the seams may align with the Achilles tendon of the wearer. In some example embodiments, overlay 510 may be a thin material or film that provides some aesthetic features for the shoe, such as design, logos, or color. The thin layer of overlay 510 may not result in irritation to the wearer if not joined with heel seam 220, as the underlying, thicker layers are joined with asymmetrical heel seam 220. In some example embodiments, overlay 510 may be a single piece of material that does not incorporate a heel seam in heel portion 140.

Referring to FIG. 6, an article of footwear 100 may include an upper having a the collar portion 150 having an inner collar lining 152, collar foam 610, attachment points 620, collar cutouts 630, and collar split 640. Collar lining 152 may be coupled to the lining of the inside of the shoe and help couple the collar to upper 102. In some example embodiments, collar cutouts 630 may align with skiving in the outsole 1104 of sole structure 130. Both collar cutouts 630 and collar split 640 may allow collar portion 150 to smoothly couple to the inner portion of heel portion 140. Collar foam 610 may be coupled to collar lining 152 via stitching or glue. In some example embodiments, collar foam 610 may have a mesh overlay. For example, the overlay for collar foam 610 may be a woven polyester mesh (e.g., a single jersey textile mesh).

In some example embodiments, collar foam 610 may include medial collar foam 614 and lateral collar foam 612. Medial collar foam 614 and lateral collar foam 612 may be asymmetrical to accommodate the natural fit of the shoe for the wearer. In some example embodiments, “natural fit” may refer to shoe contouring the shape of the back of the, e.g., the heel having a wider base at the bottom of the foot and narrowing slightly following the Achilles tendon up the ankle. The asymmetry may have a medial bias that contours this narrowing by wrapping around the medial side of the heel. As discussed with reference to heel seam 220, the term “asymmetric” as used throughout this detailed description and in the claims refers to any arrangement of a component of the shoe that does not extend symmetrically over medial side 104 and the lateral side 106 of upper 102.

FIG. 6 includes a three dimensional, x, y, and z axis for reference. For the purposes of this disclosure, the x-direction refers to width, the y-direction refers to height, and the z-direction refers to depth or thickness. Medial collar foam 614 may have a greater height or width than lateral collar foam with reference to the y and x-directions of the reference axis. For example, with reference to in FIG. 6, medial collar foam 614 may be larger than lateral collar foam 612 with reference to the y-direction of the reference axis such that the height is greater. In some example embodiments, medial collar foam 614 may also or alternatively may be thicker than lateral collar foam 612 in the z-direction and/or x-direction of the reference axis. Medial collar foam 614 and lateral collar foam 612 may have symmetry in the z-direction and/or x-direction of the reference axis. The asymmetrical medial collar foam 614 and lateral collar foam 612 may be configured to accommodate the natural fit of the wearer, allowing the shoe to fit tighter, while increasing comfort for the wearer.

In some example embodiments, collar foam 610 may include one or more layers configured to increase foam rebound and slow recovery with dual density foam layers and thermoplastic polyurethane (TPU). The layered foam design may be configured to adapt to the heel geometry of the wearer and provide a natural, semi-custom fit. In some example embodiments, collar foam 610 may include three layers. Each of the three layers, e.g., top foam layer 710, middle layer 720, and/or bottom foam layer 730, may have a different thickness and/or material and be described with reference to FIGS. 7A-C, respectively. Further, each of the foam layers 710, 720, and/or 730 may have the same geometry and asymmetry as collar foam 610.

FIG. 7A illustrates top foam layer 710 including lateral side 712.1, medial side 714.1, cutouts 718.1, and separation 716. Top foam layer 710 may be asymmetrical such that medial side 714.1 extends further in the y-direction than lateral side 712.1, as described with reference to FIG. 6. In some example embodiments, top foam layer 710 may consist of a low density polyurethane (PU) foam, e.g., a 2 millimeter PU foam with a hardness between 74-80 and density of 0.05-0.09 pounds per cubic foot (PCF). The PU foam may be a synthetic suede material with a knit base rather than a nonwoven base. The synthetic suede material allows the foam to hold its shape under pressure, rather than flatten a conventional PU foam materials might. The ability of the PU foam layers to hold shape contribute to the semi-custom fit of the shoe. Cutouts 718.1 may be configured to allow collar portion 150 to smoothly couple to the insole of article 100.

In some example embodiments, top foam layer 710 may also include separation 716. Lateral side 712.1 and medial side 714.1 may be vertically separated at the horizontal center of top foam layer 710. Separating lateral side 712.1 and medial side 714.1 may prevent creasing when inner collar lining 152 is coupled with the insole of article 100. Separation 716 may be form by first cutting a vertical line in top foam layer 710 at the horizontal center. The line may be cut to create a hole in the center of top foam layer 710 and then fully separate lateral side 712.1 and medial side 714.1.

FIG. 7B illustrates middle layer 720 including lateral side 712.2, medial side 714.2, and cutouts 718.2. Middle layer 720 may be asymmetrical such that medial side 714.2 extends further in the y-direction than lateral side 712.2, as described with reference to FIG. 6. In some example embodiments, middle foam layer 720 may consist of a thermoplastic polyurethane foam layer (TPU). The TPU material may be configured to melt or activate between 60-75 degrees Celsius with a hardness of 62-77 and density of 0.08-0.12 PCF. The melting point of the TPU material of middle layer 720 allows collar foam 610 to hold its shape during wear, which may put increased pressure on heel portion 140. Bottom foam layer 730 and top foam layer 710 provide cushioning to create the semi-custom fit of heel portion 140 and collar portion 150. Cutouts 718.2 may be configured to allow collar portion 150 to smoothly couple to the insole of article 100. In some example embodiments, middle layer 720 may include hole 722. Similar to separation 716, hole 722 may allow the layers of collar foam 610 to be laminates and curve around opening 103 and/or heel portion 140 without creasing. Reducing the creasing of collar portion 150 may allow for a tighter fit for the wearer.

FIG. 7C illustrates bottom foam layer 730 including lateral side 712.3, medial side 714.3, and cutouts 718.3. Bottom foam layer 730 may be asymmetrical such that medial side 714.3 extends further in the y-direction than lateral side 712.3, as described with reference to FIG. 6. Bottom foam layer 730 may be made of a high density polyurethane (PU) foam, e.g., a 4 millimeter PU foam with a hardness between 74-80 and density of 0.05-0.09 PCF. The PU foam may be a synthetic suede material with a knit base rather than a nonwoven base. The synthetic suede material allows the foam to hold its shape under pressure, rather than flatten a conventional PU foam materials might. The ability of the PU foam layers to hold shape contribute to the semi-custom fit of the shoe. Cutouts 718.3 may be configured to allow collar portion 150 to smoothly couple to the insole of article 100.

In addition to the asymmetry of collar foam 610, outer collar lining 156 may have asymmetry with viewing collar portion 150 from the medial, lateral, and heel portions as shown in FIGS. 8A-C, respectively. The orientation of inner collar lining 152 within the shoe may result in asymmetry in outer collar lining 156. For example, outer collar lining 156 may dip below the medial malleolus bone of the wearer, as show in FIG. 8B. The asymmetry of collar portion 150 is also shown in FIG. 8C, when viewing heel portion 140 from the rear. Medial collar foam 614 is configured to provide additional cushion around the medial malleolus bone and provide a better fit for the wearer. As a results the medial side of outer collar lining 156 may dip below the medial malleolus bone and asymmetrical compared to the lateral side of outer collar lining 156. Similarly, heel seam 220 may have an asymmetrical bias toward medial side 104. These features may result in asymmetry of outer collar lining 156.

FIG. 9 illustrates a top view of the exemplary embodiment of the article of footwear of FIG. 1 including a fastening system and tongue. Tongue 110 may include a tongue foam 910 and fastening system 120. Fastening system 120 may be implemented as lacing system 120 and include laces 122. Lacing system 120 configured with first end portion 123 and second end portion 124. Lacing system 120 may be configured to be tightened to secure a wearer's foot in upper 102. Lacing system 120 may be tightened such that the wearer's foot is secure, but first end portion 123 may irritate that top of the wearer's foot. For example, when laces 122 are tightened and tied at first end portion 123 the laces, knot, or a combination may rub against tongue 110 and irritate the wearer's foot. Further, during many athletic activities, the wearer may move their ankle causing tongue 110 and first end portion 123 to rub against the top of wearer's foot.

In some example embodiments, article 100 may include tongue foam 910 to prevent the irritation caused by lacing system 120. Tongue foam 910 may be disposed on the underside of tongue 110, as shown in FIG. 9. Tongue foam 910 may be couple to tongue 110 anywhere along tongue 110 and lacing system 120 may cause irritation to the wearer's foot. For example, to prevent irritation to the wearer's foot at first end portion 123, tongue foam 910 may be coupled to tongue 110 at first end portion 123. Tongue foam 910 may provide a cushioned buffer between laces 122 and tongue 110 with the top of the wearer's foot.

In some example embodiments, fastening system 120 may be a system other than a lacing system, such as a zipper mechanism or hook and loop. Fastening system 120 may also fasten in a location other than first end portion 123, such as second end portion 124 or with a bias toward medial side 104 or lateral side 106. Tongue foam 910 may be coupled to tongue 110 where irritation due to fastening system 120 may occur. In some example embodiments, tongue 110 may include multiple instances of tongue foam 910 where fastening system 120 causes multiple points of irritation.

FIG. 10 illustrates a partial view of tongue foam 910 coupled to tongue 110. Tongue foam 910 may be coupled to tongue 110 on the underside of tongue 110 to adjust the softness of tongue 110. Tongue foam 910 may create a barrier between tongue 110 and the wearer's foot. In some example embodiments, tongue foam 910 may be tapered. For example, tongue foam 910 may be wider nearer to first end portion 123 and taper to a smaller width near second end portion 124. In some example embodiments, tongue foam 910 may have a uniform thickness, e.g., 6 mm. In other example embodiments, the thickness of tongue foam 910 may taper corresponding to the tapered shape, e.g., 6 mm at first end portion 123 and 2 mm at second end portion 124. The thickness of tongue foam 910 may be adjusted to accommodate the design of tongue 110 and fastening system 120. This may allow tongue foam 910 to provide cushion between tongue 110 and the wearer's foot where fastening system 120 may be most likely to cause irritation, e.g., where the laces are tied at first end portion 123, without adding additional weight to article 100. Tongue foam 910 may take a different size and/or shape, i.e., any regular or irregular shape, to accommodate tongue 110 and fastening system 120 of article 100.

Some conventional embodiments may add a foam layer to the tongue, however these foam layers may be concentric and cover the entire or a majority of the tongue. Tongue foam 910 may be configured to increase the softness of tongue 110 and provide a barrier for the wearer's foot, without increasing the weight of the shoe. Additionally, in some embodiments, article 100 may be a soccer cleat designed for high performance play. As a result, a tight fit is important to the performance of the shoe. Traditional large thick foam pieces impede the ability of the shoe to have a tight fit for the wearer.

Tongue foam 910 may be consist of a polyurethane (PU) foam. In some embodiments, the PU foam of tongue foam 910 may partially consist of recycled thermoplastic polyurethane (TPU). The PU foam of tongue foam 910 may be configured to stretch with the knit construction of tongue 110 without decoupling from tongue 110 during wear. Additionally, the PU foam may hold its shape without flattening under pressure of fastening system 120 and increased heat of the wear's foot and/or article 100 during wear and activity. Tongue foam 910 may be coupled to tongue 110 using a thin film with a low melting point, e.g., a hot melt adhesive (HMA) of 95 degrees Celsius. The film may contribute to the ability of tongue foam