Patent Description:
Footwear typically includes a sole structure configured to be located under a wearer's foot to space the foot away from the ground or floor surface. Athletic footwear in particular sometimes utilizes polyurethane foam, rubber, and/or other resilient materials in the sole structure to provide cushioning.

<CIT> discloses an article of footwear according to the preamble of claim <NUM>.

The present disclosure generally relates to an article of footwear that may have features beneficial for certain activities. For example, the article of footwear may include a sole structure that provides greater support at a medial side of the sole structure for extra loading that may occur during activities such as weightlifting, that includes features for easing inverted wall pushups, and that includes features for efficiency in rope climbing.

The claimed invention provides an article of footwear as defined in appended independent claim <NUM>. Specific embodiments thereof are defined in the appended dependent claims. In particular, the article of footwear comprises a sole structure including a heel cushioning unit. The heel cushioning unit has a top portion, a bottom portion, a body portion connecting the top portion to the bottom portion, medial support fins in a medial side recess defined by the heel cushioning unit at a medial side of the heel cushioning unit and lateral support fins in a lateral side recess defined by the heel cushioning unit at a lateral side of the heel cushioning unit. Both the medial support fins and the lateral support fins extend transversely outward from the body portion and from the top portion to the bottom portion. The heel cushioning unit defines a through hole extending from the medial side to the lateral side and disposed rearward of the medial support fins and the lateral support fins.

Because the medial and lateral support fins extend outward from the body portion, they provide greater resistance to compression (e.g., greater stiffness) than if they were separated from the body portion. In contrast, the transversely-extending through hole increases the compressibility of the heel cushioning unit in the vertical direction (e.g., under compressive loading of the top portion toward the bottom portion). The orientation and number of the support fins are selected to tune the compressibility of the heel cushioning unit.

Additionally, a rear wall of the heel cushioning unit encloses the through hole rearward of the through hole and may extend from the top portion to the bottom portion of the heel cushioning unit. The rear wall may contribute to the heel cushioning unit resiliently returning to an initial state when compressive loading is reduced. Other features such as a beveled upper edge of the heel cushioning unit and a heel guard help to reduce friction and ease sliding against a wall during inverted wall pushups.

In another aspect, an upper may be coupled to the sole structure, and the sole structure may further comprise an outsole underlying a bottom surface of the heel cushioning unit. The outsole may have an arch portion wrapping upward along and secured to a side surface of the upper above a biteline between the sole structure and the upper. A side shield may extend upward from the arch portion along the side surface of the upper. An exterior of the side shield and/or an exterior of the arch portion may include stepped ridges extending lengthwise in a fore-aft direction of the article of footwear. Each stepped ridge may be relatively thicker at a lower extent of the stepped ridge than at an upper extent of the stepped ridge such that the stepped ridge angles outward from the upper extent to the lower extent. This configuration enables the stepped ridges to provide grip in one direction of movement while promoting ease of sliding in the opposite direction of movement.

Additionally, each stepped ridge may include a series of linear segments along its length. The linear segments may include a center linear segment, a front linear segment extending forward and downward from the center linear segment at an obtuse angle, and a rear linear segment extending rearward and downward from the center linear segment at an obtuse angle. This configuration of the linear segments helps to increase friction against an object held against the stepped ridges, such as a rope during rope climbing. The angles between the center linear segment and the front and rear linear segments enable the segments to act as a wedge against movement of the arch portion and/or side shield relative to the rope.

Still further, the side shield may define an aperture, and a tensioning cable may extend through the aperture from an inner side of the side shield to an outer side of the side shield. A lace or other component of a tensioning system may engage the tensioning cable to tighten the side shield against the upper and toward the side of the foot. Conforming the side shield to the shape of the foot via the tensioning cable in this manner may increase the ability of the wearer to sense the position of an object against the side shield such as during rope climbing.

Referring to the drawings, wherein like reference numbers refer to like components throughout the views, <FIG> shows an article of footwear <NUM> that includes a sole structure <NUM> and an upper <NUM> secured to the sole structure <NUM>. The sole structure <NUM> includes a midsole layer <NUM> which may be, for example, a resilient foam. The upper <NUM> is secured to a top surface <NUM> of the midsole layer <NUM>, as best shown in <FIG>. For example, the upper <NUM> may be adhered to the top surface <NUM>. A biteline <NUM> shown in <FIG> denotes the junction or intersection of the midsole layer <NUM> and the upper <NUM>, and is coincident with an upper edge <NUM> of the midsole layer <NUM>.

The upper <NUM> forms a foot-receiving cavity <NUM> configured to receive a foot. The article of footwear <NUM> may be referred to as footwear <NUM>, and as illustrated herein is depicted as athletic footwear specifically configured for activities such as weightlifting, rope climbing, running, and inverted wall pushups, or for various other activities that may be undertaken during crossfit training or competition, or during other athletic endeavors. Although the article of footwear <NUM>, including the sole structure <NUM>, may be athletic footwear, it may instead be worn and used as a leisure shoe, a dress shoe, a work shoe, a sandal, a slipper, a boot, or as footwear in any other category of footwear.

As indicated in <FIG>, the article of footwear <NUM> may be divided into a forefoot region <NUM>, a midfoot region <NUM>, and a heel region <NUM>, which are also the forefoot region, the midfoot region, and the heel region, respectively, of the sole structure <NUM> and the upper <NUM>. The forefoot region <NUM> generally includes portions of the article of footwear <NUM> corresponding with the toes and the metatarsophalangeal joints (which may be referred to as MPT or MPJ joints) connecting the metatarsal bones of the foot and the proximal phalanges of the toes. The midfoot region <NUM> generally includes portions of the article of footwear <NUM> corresponding with the arch area and instep of the foot, and the heel region <NUM> generally corresponds with rear portions of the foot, including the calcaneus bone. The forefoot region <NUM>, the midfoot region <NUM>, and the heel region <NUM> are not intended to demarcate precise areas of the article of footwear <NUM>, but are instead intended to represent general areas of the article of footwear <NUM> to aid in the following discussion.

The article of footwear <NUM> has a medial side <NUM> (shown in <FIG>) and a lateral side <NUM> (shown in <FIG>). The medial side <NUM> and the lateral side <NUM> extend through each of the forefoot region <NUM>, the midfoot region <NUM>, and the heel region <NUM>, and correspond with opposite sides of the article of footwear <NUM>, each falling on an opposite side of a longitudinal midline LM of the article of footwear <NUM>, indicated in <FIG>. The medial side <NUM> is thus considered opposite to the lateral side <NUM>.

The upper <NUM> may be a variety of materials, such as leather, textiles, polymers, cotton, foam, composites, etc. For example, the upper <NUM> may be a polymeric material capable of providing elasticity, and may be of a braided construction, a knitted (e.g., warp-knitted) construction, or a woven construction. A lower extent of the upper <NUM> is secured to a periphery of the sole structure <NUM> as shown in <FIG>. The top surface <NUM> of the midsole layer <NUM> (shown in <FIG> and <FIG>) may be covered by a strobel (not shown) secured to the lower extent of the upper <NUM>. Alternatively, the upper <NUM> may be a <NUM>-degree sock-like or bootie-like upper that extends under the foot and over the top surface <NUM>. An insole (not shown) may rest in the foot-receiving cavity <NUM> on the top surface <NUM>.

The midsole layer <NUM> may be at least partially a polyurethane foam, or a polyurethane ethylene-vinyl acetate (EVA) foam and may include heat-expanded and molded EVA foam pellets. The midsole layer <NUM> may generally include phylon (ethylene vinyl acetate or "EVA") and/or polyurethane ("PU") base resins. For example, in one embodiment, the midsole layer <NUM> may be a compression molded phylon. If EVA is used, it may have a vinyl acetate (VA) level between approximately <NUM>% and approximately <NUM>%. Suitable EVA resins include Elvax®, provided by E. du Pont de Nemours and Company, and Engage™, provided by the Dow Chemical Company, for example. In certain embodiments, the EVA may be formed of a combination of high melt index and low melt index material. For example, the EVA may have a melt index of from about <NUM> to about <NUM>. The EVA resin may be compounded to include various components including a blowing agent and a curing/crosslinking agent. The blowing agent may have a percent weight between approximately <NUM>% and approximately <NUM>%. The blowing agent may be thermally decomposable and may be selected from ordinary organic and inorganic chemical blowing agents. The nature of the blowing agent is not particularly limited as long as it decomposes under the temperature conditions used in incorporating the foam into the virgin resin. Suitable blowing agents include azodicarboamide, for example. In certain embodiments, a peroxide-based curing agent, such as dicumyl peroxide may be used. The amount of curing agent may be between approximately <NUM>% and approximately <NUM>%. The EVA may also include homogenizing agents, process aids, and waxes. For example, a mixture of light aliphatic hydrocarbons such as Struktol® 60NS, available from Schill+Seilacher "Struktol" GmbH, may be included to permit other materials or scrap EVA to be more easily incorporated into the resin. The EVA may also include other constituents such as a release agent (e.g., stearic acid), activators (e.g., zinc oxide), fillers (e.g., magnesium carbonate), pigments, and clays. In embodiments that incorporate multiple materials, each material may be formed from a material that is compatible and readily bonds with the other material. For example, the materials may each be formed from an EVA resin with suitable blowing agents, crosslinking agents, and other ancillary components, pigments, fillers, and the like. Other suitable materials will become readily apparent to those skilled in the art, given the benefit of this disclosure.

In addition to the midsole layer <NUM>, the sole structure <NUM> includes a heel cushioning unit <NUM>, a heel guard <NUM>, an outsole <NUM>, and a side shield <NUM>. The heel cushioning unit <NUM> underlies the midsole layer <NUM> in the heel region <NUM>, and the heel guard <NUM> extends along a rear surface <NUM> of the midsole layer <NUM>. The outsole <NUM> underlies a bottom surface <NUM> (<FIG>) of the midsole layer <NUM> and has a bottom portion 48A (<FIG>), a medial arch portion 48B (<FIG>) and a lateral arch portion 48C (<FIG>). The medial arch portion 48B extends upward along a medial side surface <NUM> of the midsole layer <NUM> in the midfoot region <NUM> and along the medial side <NUM> of the upper <NUM>. The medial arch portion 48B is secured to the medial side <NUM> above the biteline <NUM>. The sole structure <NUM> also includes a side shield <NUM> extending from the medial arch portion 48B further up the medial side <NUM> of the upper <NUM> and secured to the medial side <NUM> of the upper <NUM>. The lateral arch portion 48C extends upward along the lateral side surface <NUM> of the midsole layer <NUM> in the midfoot region <NUM>. The lateral arch portion 48C is secured to the lateral side <NUM> of the upper <NUM> above the biteline <NUM>. Features of each of these components are discussed in greater detail herein.

<FIG> show the heel cushioning unit <NUM> in isolation. The heel cushioning unit <NUM> has a body portion 42A, also referred to as a central body portion, that is best shown in <FIG> and <FIG>. Although the heel cushioning unit <NUM> is shown as a single, unitary component, it need not be a single component but instead can be multiple interconnected components. The heel cushioning unit <NUM> defines a medial side recess <NUM> at a medial side 38A of the heel cushioning unit <NUM>, which is at the medial side <NUM> of the article of footwear <NUM> when assembled in the sole structure <NUM>. The heel cushioning unit <NUM> defines a lateral side recess <NUM> at a lateral side 40A of the heel cushioning unit <NUM>, which is at the lateral side <NUM> of the article of footwear <NUM> when assembled in the sole structure <NUM>. Both the medial side recess <NUM> and the lateral side recess <NUM> extending transversely inward to the central body portion 42A. The medial side recess <NUM> and the lateral side recess <NUM> separate a top portion 42B of the heel cushioning unit <NUM> from a bottom portion 42C of the heel cushioning unit <NUM>. The top portion 42B is disposed above the medial side recess <NUM> and the lateral side recess <NUM>, and the bottom portion 42C is disposed below the medial side recess <NUM> and the lateral side recess <NUM>. Stated differently, the top portion 42B flares upward from the body portion 42A, and the bottom portion 42C flares downward from the body portion 42A.

Referring to <FIG>, the top surface <NUM> of the heel cushioning unit <NUM> is concave to follow the shape of a wearer's foot, and extends to an upper extent <NUM>. The bottom surface <NUM> of the heel cushioning unit <NUM> is concave under the central body portion 42A, as best shown in <FIG> and <FIG>. A top surface of the bottom portion 48A of the outsole <NUM> underlies and confronts a portion of the bottom surface <NUM> of the heel cushioning unit <NUM>, as is evident in <FIG>, <FIG>, <FIG>, and <FIG>, when considered together.

As best shown in <FIG>, the heel cushioning unit <NUM> includes medial support fins <NUM> disposed in the medial side recess <NUM>, extending transversely outward from the body portion 42A, and extending from the top portion 42B to the bottom portion 42C. There are three medial support fins <NUM>, but there could be less than three or more than three. Similarly, as shown in <FIG>, the heel cushioning unit <NUM> includes lateral support fins <NUM> disposed in the lateral side recess <NUM> and extending transversely outward from the body portion 42A, and also extending from the top portion 42B to the bottom portion 42C. The body portion 42A extends continuously in a transverse direction from the medial support fins <NUM> to the lateral support fins <NUM>. There are two lateral support fins <NUM>, but there could be fewer or more than two. As shown, the number of medial support fins <NUM> is greater than the number of lateral support fins <NUM>. The support fins <NUM> and <NUM> provide resistance to compression of the top portion 42B toward the bottom portion 42C. By having a greater number of medial support fins <NUM> than lateral support fins <NUM>, greater support and resistance to compression (e.g., greater compressive stiffness) is provided at the medial side 38A than at the lateral side 40A, assuming that each support fin <NUM>, <NUM> provides a relatively equal resistance to compression, such as by being of equal thickness in the longitudinal direction (e.g., the fore-aft direction). Accordingly, during activities that tend to load the medial side 38A more than the lateral side 40A, such as during some weightlifting moves, the greater number of medial support fins <NUM> will provide the medial side 38A with greater resistance to compression to counteract the greater medial side loading, as discussed with respect to <FIG>. Both the medial support fins <NUM> and the lateral support fins <NUM> angle forwardly and upwardly from the bottom portion 42C to the top portion 42B of the heel cushioning unit <NUM> as shown in <FIG>, respectively. This forward angle reduces the resistance to compression in comparison to a completely vertical fin.

In addition to the medial and lateral side recesses <NUM>, <NUM>, the heel cushioning unit <NUM> defines a through hole <NUM> extending from the medial side 38A to the lateral side 40A and disposed rearward of the medial support fins <NUM> and the lateral support fins <NUM>. The through hole <NUM> is in communication with and connects the medial and lateral side recesses <NUM>, <NUM>, as best shown in <FIG>. The heel cushioning unit <NUM> has a rear wall 42D that extends from the bottom portion 42C to the top portion 42B and encloses the through hole <NUM> rearward of the through hole <NUM>. As best shown in <FIG>, the rear wall 42D is wider in a transverse direction at the bottom portion 42C than at the top portion 42B. More specifically, the rear wall 42D has a first width W1 at the bottom portion 42C, and tapers to a lesser second width W2 at the top portion 42B. The wider first width W1 provides stability while the taper to a lesser second width W2 enables the top portion 42B of the heel cushioning unit <NUM> to more readily resiliently deflect toward the bottom portion 42C, such as under dynamic loading.

As also shown in <FIG>, the heel cushioning unit <NUM> includes ribs 42E that extend along the lower surface <NUM> of the top portion 42B from the medial side 38A to the lateral side 40A over the through hole <NUM>. Accordingly, the ribs 42E extend into the through hole <NUM>. The ribs 42E may help strengthen the top portion 42B. As best shown in <FIG>, the top surface <NUM> is concave, and the bottom surface <NUM> of the body portion 42A is also concave. The concavity at the bottom surface <NUM> may be lessened as the heel cushioning unit <NUM> partially flattens under dynamic loading. The heel cushioning unit <NUM> returns to the concave shape at the bottom surface <NUM> once dynamic external stresses are removed. The concavity at the bottom surface <NUM> thus enables resilient deflection of the body portion 42A under dynamic compressive loading.

Referring again to <FIG>, the heel cushioning unit <NUM> includes a beveled upper edge <NUM> at the upper extent <NUM> and extending around a rear <NUM> of the heel cushioning unit <NUM> from the medial side 38A to the lateral side 40A. The beveled upper edge <NUM> includes an upper bevel 76A and a lower bevel 76B that meet at an edge 76C. The edge 76C is the rearmost extent of the heel cushioning unit <NUM> and also the rearmost extent of the article of footwear <NUM> when the heel cushioning unit <NUM> is assembled in the sole structure <NUM>. The edge 76C serves as a relatively low friction, low surface area contact region for the article of footwear <NUM> such as when used for performing inverted wall pushups, as discussed with respect to <FIG>.

Generally, the heel cushioning unit <NUM> may be a relatively rigid material or combination of materials. For example, the heel cushioning unit <NUM> may comprise a thermoplastic elastomer. In other examples, in one or more embodiments, the heel cushioning unit <NUM> may comprise a carbon fiber, a carbon fiber composite (such as a carbon fiber-filled nylon), a fiberglass-reinforced nylon, which may be an injected, fiber-reinforced nylon, a fiber strand-lain composite, a thermoplastic polyurethane, wood, steel, or another material or combinations of these, but is not limited to these materials. In addition to their geometry, the materials selected for the heel cushioning unit <NUM> may result in desired performance characteristics. In one example, the heel cushioning unit <NUM> may be a polyether block amide PEBAX®, available from Arkema, Inc. in King of Prussia, Pennsylvania USA.

The heel cushioning unit <NUM> may be referred to as a plate. As used herein, the term "plate", refers to a member of a sole structure that has a width greater than its thickness and is generally horizontally disposed when assembled in an article of footwear with the sole structure resting on a level ground surface, so that its thickness is generally in the vertical direction and its width is generally in the horizontal direction. A plate may be a single, unitary component of multiple interconnected components. Portions of a plate can be flat, and portions can have some amount of curvature and variations in thickness when molded or otherwise formed, for example, to provide a shaped footbed and/or increased thickness for reinforcement in desired areas.

<FIG> shows the heel guard <NUM> having a generally arcuate shape extending from a medial edge <NUM> to a lateral edge <NUM>. The heel guard <NUM> includes an upper portion <NUM> and a lower portion <NUM> recessed at the outer side relative to the upper portion <NUM> such that the upper portion <NUM> defines a lip <NUM>. An inner surface <NUM> of the heel guard <NUM> is generally concave in both the transverse and vertical directions so that the heel guard <NUM> fits flush against and is adhered or otherwise secured to the midsole layer <NUM> as shown in <FIG>, with the lower portion <NUM> extending under to the bottom surface <NUM> of the midsole layer <NUM>, and the upper portion <NUM> extending upward along the rear surface <NUM> of the midsole layer <NUM>. The heel guard <NUM> extends forward along the medial side surface <NUM> of the midsole layer <NUM>, and forward along the lateral side surface <NUM> of the midsole layer <NUM> (see <FIG>). The lip <NUM> is the furthest outward extent of the heel guard <NUM> when the heel guard <NUM> is secured to the midsole layer <NUM>.

The lower portion <NUM> of the heel guard <NUM> is configured to fit flush against and be disposed on the inner surface 64A (see <FIG>) of the top portion 42B of the heel cushioning unit <NUM> when the midsole layer <NUM> is disposed on the top portion 42B of the heel cushioning unit <NUM> with the bottom surface <NUM> of the midsole layer <NUM> secured to the top surface <NUM> of the heel cushioning unit <NUM>. The lower portion <NUM> is thus disposed between the midsole layer <NUM> and the heel cushioning unit <NUM>, and the upper portion <NUM> extends upward above the beveled upper edge <NUM> and along the rear surface <NUM> of the midsole layer <NUM>. The lip <NUM> rests on the upper extent <NUM> of top portion 42B above the beveled upper edge <NUM> as best shown in <FIG>.

As best shown in <FIG>, the heel guard <NUM> is asymmetrical about the longitudinal midline LM of the article of footwear <NUM> because the lateral edge <NUM> of the heel guard <NUM> extends further forward than the medial edge <NUM> of the heel guard <NUM> when the sole structure <NUM> is assembled. This configuration may be beneficial during inverted wall pushups (illustrated in <FIG>), as the feet may tend to splay with the toes pointing outward so that the sole structure <NUM> contacts a wall <NUM> more on the lateral side <NUM> of the sole structure <NUM> than on the medial side <NUM>. In the embodiment shown, the heel guard <NUM> is of a harder material with a lower coefficient of friction than the relatively soft midsole layer <NUM>. For example, the heel guard <NUM> may be any of the materials described herein with respect to the heel cushioning unit <NUM>. The heel guard <NUM> may reduce any sliding friction against the wall <NUM> if the feet are tipped so that the heel guard <NUM> contacts the wall <NUM> rather than just the beveled upper edge <NUM> of the heel cushioning unit <NUM> contacting the wall <NUM>. Additionally, as shown in <FIG> and <FIG>, the outer surface of the upper portion <NUM> of the heel guard <NUM> has linear recesses <NUM> that extend parallel with one another. At least along the rear of the heel guard <NUM>, the linear recesses <NUM> tilt upward and toward the lateral side of the heel guard <NUM> from their lowest extent to their highest extent, as best shown in <FIG>. During inverted wall pushups, the linear recesses <NUM> may be disposed vertically against the wall <NUM> due to the splay and tilt of the feet. In such an orientation, the recesses <NUM> will be in the direction of movement of the article of footwear <NUM> against the wall <NUM> (e.g., vertically up and down as shown by double-sided arrows A1 and A2 in <FIG>). This may reduce contact area and frictional forces of the heel guard <NUM> against the wall <NUM>.

<FIG> illustrates the side shield <NUM> extending upward from the medial arch portion 48B. A lower flange 58A of the side shield <NUM> (shown in <FIG>) is secured to the inner side of the medial arch portion 48B as best shown in <FIG>, such as with adhesive and/or by thermal bonding. The side shield <NUM> may be a different material than the outsole <NUM> from which it extends. In this manner, the side shield <NUM> may be optimized for grip in one direction and sliding in an opposite direction during rope climbing, as discussed herein, while the outsole <NUM> may be optimized for the same functionality, and further optimized for wear resistance and traction. Alternatively, the side shield <NUM> and the outsole <NUM> could be a unitary, one-piece component so that the medial arch portion 48B and the side shield <NUM> are portions of the same component rather than separate components attached at the lower flange 58A. If the side shield <NUM> and the outsole <NUM> are a unitary, one-piece component, then no lower flange 58A would be included as the side shield <NUM> would extend integrally from the medial arch portion 48B without any flange attachment between the two portions being necessary. In either embodiment, the side shield <NUM> may be of the same material as the outsole <NUM>. The outsole <NUM> may be formed from materials that may generally include natural or synthetic rubber or other suitably durable materials. The material or materials for the outsole <NUM> may be selected to provide a desirable combination of durability and flexibility. Synthetic rubbers that may be used include polybutadiene rubber, ethylene propylene rubber (EPR), styrene isoprene styrene (SIS) copolymer rubber, and styrene butadiene rubber.

Referring to <FIG>, the side shield <NUM> defines vent openings <NUM> that extend through the side shield <NUM> from an inner side <NUM> of the side shield <NUM> to an outer side <NUM> of the side shield <NUM>. The outer side <NUM> is also referred to as the exterior of the side shield <NUM>. The vent openings <NUM> permit venting of the foot-receiving cavity <NUM> (see <FIG>), through the upper <NUM>, and out through the vent openings <NUM>. Similarly, the medial arch portion 48B also has vent openings <NUM> extending through the medial arch portion 48B, as best shown in <FIG>. Only some of the vent openings <NUM> are labelled in <FIG>.

As also shown in <FIG>, the side shield <NUM> defines two elongated apertures <NUM> that may be referred to as slits. The elongated apertures <NUM> extend upwardly from their rearmost extent to their foremost extent at an angle relative to the longitudinal midline LM of the article of footwear <NUM> ( and at an angle relative to a vertical axis) when the side shield <NUM> is secured on the article of footwear <NUM>, as shown in <FIG>. The side shield <NUM> also defines three apertures <NUM> extending though the side shield <NUM> from the inner side <NUM> to the outer side <NUM>. Two of the apertures <NUM> are above a respective one of the elongated apertures <NUM> (e.g., above the rearmost aperture <NUM>).

Referring again to <FIG>, the article of footwear <NUM> includes tensioning cables <NUM>, some of which extend through the elongated apertures <NUM> from the inner side <NUM> to the outer side <NUM> such that looped portions of the tensioning cables <NUM> extend outward of the outer side <NUM>. The tensioning cables <NUM> may be secured to the upper <NUM> inward of the side shield <NUM> and may, in some configurations, be secured to the sole structure <NUM>, extending up from the sole structure <NUM> along or within the upper <NUM> and then through the elongated apertures <NUM>. The article of footwear <NUM> may also include a lace <NUM> or other tensioning member that extends though the looped portions of the tensioning cables <NUM>, and may be tightened to help tension the side shield <NUM> and the medial arch portion 48B against the upper <NUM> and the foot therein. Additional looped cables <NUM> are shown forward of the side shield <NUM>, and the lace <NUM> also extends through these looped cables, as well as looped cables <NUM> extending upward along the lateral side <NUM> of the upper <NUM> (some of which are visible in <FIG>).

As best shown in <FIG>, the exterior of the side shield <NUM> (e.g. the outer side <NUM>) and the exterior of the medial arch portion 48B (e.g., the outer side <NUM> of the medial arch portion 48B) includes stepped ridges <NUM>, only some of which are indicated by reference number in <FIG>. Each stepped ridge <NUM> extends lengthwise in the fore-aft direction of the article of footwear <NUM> (e.g., generally in a direction that extends from the forefoot region <NUM> to the heel region <NUM>, such as in a direction along the longitudinal midline LM). Stated differently, each stepped ridge <NUM> is longer in the fore-aft direction than in the vertical direction. As best shown in <FIG>, each stepped ridge <NUM> is relatively thicker at a lower extent 110A of the stepped ridge <NUM> than at an upper extent 110B of the stepped ridge such that the stepped ridge <NUM> angles outward from the upper extent 110B to the lower extent 110A. As shown in <FIG>, the vent openings <NUM> extend in rows along the stepped ridges <NUM>, each row extending through one of the stepped ridges <NUM> between the upper extent 110B and the lower extent 110A. As shown in <FIG>, the lateral arch portion 48C also has stepped ridges <NUM>. Moreover, at least some of the stepped ridges <NUM> underlie the midsole layer <NUM>. The tensioning cables <NUM> and the lace <NUM> are not shown in <FIG> for clarity in the drawings in order to focus on the features of the medial arch portion 48B and the side shield <NUM>.

Referring to <FIG>, the height H of each stepped ridge <NUM> is greater than the width W of its underside where the width W is measured generally in a transverse direction of the article of footwear <NUM>. With this configuration, and by angling outward from the upper extent 110B to the lower extent 110A, the stepped ridges <NUM> tend to grip an object contacting the stepped ridges <NUM> and provide greater friction and resistance to movement of the object in a direction from the lower extent 110A toward the upper extent 110B, as the protruding lower edge <NUM> of each stepped ridge <NUM> functions like a hook or barb and tends to dig into and/or created greater friction against the object. In contrast, an object contacting the stepped ridges <NUM> encounters relatively low resistance to movement in a direction from the upper extent 110B toward the lower extent 110A, as the object can slide over the stepped ridge <NUM> and past the protruding lower edges <NUM>. Accordingly, with reference to <FIG>, when the article of footwear <NUM> is worn during climbing of a rope <NUM>, the article of footwear <NUM> can move up against the rope <NUM> with little or no resistance from the stepped ridges <NUM>, and then grip the rope <NUM> via the stepped ridges <NUM> once weight is pressed downward against the rope <NUM>, as shown in <FIG>.

Referring again to <FIG>, each stepped ridge <NUM> includes a series of linear segments 110C, 110D, and110E along its length. The linear segments include a center linear segment 110C, a front linear segment 110D extending forwardly and downwardly from the center linear segment 110C at a first obtuse angle B1, and a rear linear segment 110D extending rearwardly and downwardly from the center linear segment 110C at a second obtuse angle B2. The linear segments 110C, 110D, 110E and angles B1, B2 are labelled with respect to only one of the stepped ridges <NUM> in <FIG> for clarity in the drawings, but apply to and describe each of the stepped ridges <NUM>. By angling the front linear segment 110D relative to the center linear segment 110C, the two segments 110C, 110D can better act as a wedge against an object such as the rope <NUM> disposed against the center linear segment 110C when movement of the rope <NUM> relative to the article of footwear <NUM> is toward the angled intersection of the segments 110C, 110D. Furthermore, if the article of footwear <NUM> is positioned against the rope <NUM> with the heel region <NUM> lower than the forefoot region <NUM>, the front linear segments 110D may extend so that they are perpendicular to the axis of the rope <NUM> along their lengths. This may improve grip in this orientation of the article of footwear <NUM>. Similarly, by angling the rear linear segment 110E relative to the center linear segment 110C, the two segments 110C, 110E can better act as a wedge against an object such as the rope <NUM> when the article of footwear <NUM> is moved relative to the rope <NUM> so that the rope <NUM> moves in a direction toward the angled intersection of the segments 110C, 110E. Furthermore, if the article of footwear <NUM> is positioned against the rope <NUM> with the heel region <NUM> higher than the forefoot region <NUM>, the rear linear segments 110E may extend so that they are perpendicular to the axis of the rope <NUM> along their lengths. This may improve grip in this orientation of the article of footwear <NUM>.

As best shown in <FIG>, the outer side <NUM> of the medial arch portion 48B is concave in the fore-aft direction, as indicated by the example surface curvature C1 representing a curve along the outer side <NUM> in a plane parallel to a horizontal ground plane when the bottom portion 48A of the outsole <NUM> is resting on the ground plane. The outer side of the lateral arch portion 48C is also concave in the fore-aft direction, as indicated by the example surface curvature C2. As also indicated in <FIG>, the bottom portion 48A of the outsole <NUM> may have two discrete sections, including a front section 48A1 and a rear section 48A2. The front section 48A1 has apertures <NUM> through which the midsole layer <NUM> is exposed. A gap <NUM> between and separating the front section 48A1 and the rear section 48A2 also exposes the midsole layer <NUM>. The arch portions 48B and 48C are integral with the rear section 48A2. Alternatively, the front section 48A1 and the rear section 48A2 may be integrally attached as a one-piece component rather than discrete components. The rear section 48A2 also has an aperture <NUM> through which the bottom surface <NUM> of the heel cushioning unit <NUM> is exposed.

As shown in <FIG>, a ground contact surface <NUM> of the outsole <NUM> (e.g., the surface of the bottom portion 48A) tapers inward from the heel region <NUM> of the outsole <NUM> to the midfoot region <NUM> of the outsole <NUM>, and tapers inward from the forefoot region <NUM> of the outsole <NUM> to the midfoot region <NUM>. A transverse width of the ground contact surface <NUM> at the midfoot region <NUM> is represented at transverse width W3, but may be taken anywhere in the midfoot region <NUM>. As used herein, a transverse width of the ground contact surface <NUM> is a width taken perpendicular to the longitudinal midline LM from the medial edge 124A of the ground contact surface <NUM> to the lateral edge 124B of the ground contact surface <NUM>. The medial edge 124A and the lateral edge 124B also denote the outer edges of the bottom portion 48A. A transverse width of the ground contact surface <NUM> at the heel region <NUM> is represented as transverse width W4 in <FIG>. A transverse width of the ground contact surface <NUM> at the forefoot region <NUM> is represented as transverse width W5 in <FIG>. The transverse width W3 of the ground contact surface <NUM> at the midfoot region <NUM> is less than the transverse width W4 of the ground contact surface <NUM> at the heel region <NUM>, and less than the transverse width W5 of the ground contact surface <NUM> at the forefoot region <NUM>. It can be seen that the transverse width of the ground contact surface <NUM> in the midfoot region <NUM> whether measured precisely at the location where the width is W3 or measured elsewhere in the midfoot region <NUM> is approximately one-third to one-half the maximum transverse width of the ground contact surface <NUM> in the heel region <NUM> and one-third to one-half the maximum transverse width of the ground contact surface <NUM> in the forefoot region <NUM>.

The medial arch portion 48B extends upward from the medial edge 124A of the ground contact surface <NUM>, and the lateral arch portion 48C extends upward from the lateral edge 124B of the ground contact surface <NUM>. The tapering of the ground contact surface <NUM> from the forefoot region <NUM> and the heel region <NUM> to the narrower transverse width W3 in the midfoot region <NUM> allows the arch portions 48B, 48C to partially underlie the midsole layer <NUM> before extending upward along the side surfaces <NUM>, <NUM> of the midsole layer <NUM> and the medial and lateral sides <NUM>, <NUM> of the upper <NUM>. Accordingly, at least some of the stepped ridges <NUM> underlie the midsole layer <NUM> in the midfoot region <NUM> as shown in both <FIG> and <FIG> (as well as in <FIG> and <FIG>). This provides an even greater surface area of the article of footwear <NUM> for gripping of the rope <NUM> as in <FIG> and allows gripping when the article of footwear <NUM> comes into contact with the rope <NUM> from many different directions and positions.

As shown in <FIG>, during crossfit rope climbing, the rope <NUM> may be clamped between the wearer's feet, with one foot (e.g., left foot LF in <FIG>) supported on and pushing against the rope <NUM> and the rope <NUM> extending over the other foot (e.g., over right foot RF in <FIG>). The article of footwear <NUM> is shown on the right foot RF and a mirror image article of footwear 10A having identical features as right foot footwear <NUM> is configured for and shown in the left foot LF. Due to the concavities of the articles of footwear <NUM>, 10A at the medial arch portions 48B, when the articles of footwear <NUM>, 10A are brought together around the rope <NUM>, the rope <NUM> is trapped in a tunnel defined by and between the two opposing medial arch portions 48B. Because the lateral arch portions 48C also have concavity in the fore-aft direction, other rope climbing techniques may be used in which the rope <NUM> is trapped between the medial arch portion 48B of one of the right and left footwear <NUM>, 10A and the lateral arch portion 48C of the other one of the right and left footwear <NUM>, 10A with the portions 48B, 48C creating a tunnel wrapping around the rope <NUM>, such as when the legs are crossed so the lateral arch portion 48C of one of the articles of footwear <NUM> or 10A faces the medial arch portion 48B of the other of the articles of footwear <NUM> or 10A.

<FIG> shows the feet RF, LF spread apart in a stance that may be taken during weightlifting, for example. In this position, more weight may be borne at the medial side 38A of the articles of footwear <NUM>, 10A than at the lateral side <NUM>. The greater number of support fins <NUM> on the medial side 38A of the heel cushioning unit <NUM> (see <FIG>) provide greater resistance to compressibility at the medial side 38A of the heel cushioning unit <NUM>, helping to tune the response to the uneven load distribution on the articles of footwear <NUM>, 10A.

<FIG> shows the wearer in an inverted position, such as when doing an inverted pushup, with the articles of footwear <NUM>, 10A moving against the wall <NUM> as discussed herein, so that the beveled upper edge <NUM> and heel guard <NUM> reduce friction as discussed with respect to <FIG>, for example.

Accordingly, the article of footwear <NUM> provides multiple components and features advantageous for efficiently carrying out various athletic activities such as during a crossfit workout or competition, including the heel cushioning unit <NUM>, the heel guard <NUM>, the outsole <NUM> with arch portions 48B, 48C and stepped ridges <NUM>, and the side shield <NUM>.

The term "longitudinal" refers to a direction extending along a length of a component. For example, a longitudinal direction of a shoe extends between a forefoot region and a heel region of the shoe. The term "forward" or "anterior" is used to refer to the general direction from a heel region toward a forefoot region, and the term "rearward" or "posterior" is used to refer to the opposite direction, i.e., the direction from the forefoot region toward the heel region. In some cases, a component may be identified with a longitudinal axis as well as a forward and rearward longitudinal direction along that axis. The longitudinal direction or axis may also be referred to as an anterior-posterior direction or axis.

The term "transverse" refers to a direction extending along a width of a component. For example, a transverse direction of a shoe extends between a lateral side and a medial side of the shoe. The transverse direction or axis may also be referred to as a lateral direction or axis or a mediolateral direction or axis.

The term "vertical" refers to a direction generally perpendicular to both the lateral and longitudinal directions. For example, in cases where a sole is planted flat on a ground surface, the vertical direction may extend from the ground surface upward. It will be understood that each of these directional adjectives may be applied to individual components of a sole. The term "upward" or "upwards" refers to the vertical direction pointing towards a top of the component, which may include an instep, a fastening region, and/or a throat of an upper. The term "downward" or "downwards" refers to the vertical direction pointing opposite the upwards direction, toward the bottom of a component and may generally point towards the bottom of a sole structure of an article of footwear.

The "interior" of an article of footwear, such as a shoe, refers to portions at the space that is occupied by a wearer's foot when the shoe is worn. The "inner side" of a component refers to the side or surface of the component that is (or will be) oriented toward the interior of the component or article of footwear in an assembled article of footwear. The "outer side" or "exterior" of a component refers to the side or surface of the component that is (or will be) oriented away from the interior of the shoe in an assembled shoe. In some cases, other components may be between the inner side of a component and the interior in the assembled article of footwear. Similarly, other components may be between an outer side of a component and the space external to the assembled article of footwear. Further, the terms "inward" and "inwardly" refer to the direction toward the interior of the component or article of footwear, such as a shoe, and the terms "outward" and "outwardly" refer to the direction toward the exterior of the component or article of footwear, such as the shoe. In addition, the term "proximal" refers to a direction that is nearer a center of a footwear component, or is closer toward a foot when the foot is inserted in the article of footwear as it is worn by a user. Likewise, the term "distal" refers to a relative position that is further away from a center of the footwear component or is further from a foot when the foot is inserted in the article of footwear as it is worn by a user. Thus, the terms proximal and distal may be understood to provide generally opposing terms to describe relative spatial positions.

While various embodiments have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the embodiments. Any feature of any embodiment may be used in combination with or substituted for any other feature or element in any other embodiment unless specifically restricted. Accordingly, the embodiments are not to be restricted except in light of the attached claims. Also, various modifications and changes may be made within the scope of the attached claims.

Claim 1:
An article of footwear (<NUM>) comprising:
a sole structure (<NUM>) including a heel cushioning unit (<NUM>); wherein the heel cushioning unit (<NUM>) has a top portion (42B), a bottom portion (42C), a body portion (42A) connecting the top portion (42B) to the bottom portion (42C), medial support fins (<NUM>) in a medial side recess (<NUM>) defined by the heel cushioning unit (<NUM>) at a medial side (38A) of the heel cushioning unit (<NUM>) and lateral support fins (<NUM>) in a lateral side recess (<NUM>) defined by the heel cushioning unit (<NUM>) at a lateral side (40A) of the heel cushioning unit (<NUM>), both the medial support fins (<NUM>) and the lateral support fins (<NUM>) extending transversely outward from the body portion (42A) and extending from the top portion (42B) to the bottom portion (42C);
wherein the heel cushioning unit (<NUM>) defines a through hole (<NUM>) extending from the medial side (38A) to the lateral side (40A) and disposed rearward of the medial support fins (<NUM>) and the lateral support fins (<NUM>); characterised in that the heel cushioning unit (<NUM>) defines a rear wall (42D) enclosing the through hole (<NUM>) rearward of the through hole (<NUM>) and extending from the top portion (42B) and to the bottom portion (42C) of the heel cushioning unit (<NUM>).