US20090313856A1

US20090313856A1 - Flexible sole for an article of footwear

Info

Publication number: US20090313856A1
Application number: US12/143,155
Authority: US
Inventors: James K. Arizumi
Original assignee: Nike Inc
Current assignee: Nike Inc
Priority date: 2008-06-20
Filing date: 2008-06-20
Publication date: 2009-12-24
Also published as: WO2009155237A3; WO2009155237A2; EP2323510A2

Abstract

A sole for an article of footwear is provided. The article of footwear defines a lateral edge, a medial edge, a forefoot region, a midfoot region and a heel region. The sole includes an outsole having a thickness and at least one slot in the outsole. The slot extends in a substantially longitudinal direction. A longitudinal centerline is defined midway between the lateral edge and the medial edge. The slot crosses over the longitudinal centerline in at least one of the forefoot region and the midfoot region. An article of footwear having the sole attached to an upper is also provided.

Description

FIELD OF THE INVENTION

The present invention relates to a sole for an article of footwear. More particularly, various examples of the invention relate to a sole having improved flexibility.

BACKGROUND OF THE INVENTION

Skateboarding has been a very popular activity for a number of years. In addition to simply riding on a skateboard, however, many skateboarders now try to perform complex tricks, which have become more and more difficult as each new generation of skateboarders tries to outdo the last.
Many skateboarding tricks require the skateboarder to apply pressure to one or the other portions of the skateboard using his or her feet, depending upon the trick they are trying to perform. This requires that skateboarders be able to apply pressure to the board through their shoes at different locations on the bottom and edges of the shoes. For example, for some tricks, pressure is applied along the lateral edge of the foot, approximately at the outer toe line location. For other tricks, pressure is applied on the lateral edge of the foot somewhat forward of the outer toe line location. For still other tricks, pressure is applied even more forward of that location, almost at the forward-most toe location of the sole.
As the interaction between the skateboarder and the skateboard is particularly important when performing such tricks, skateboarders typically prefer shoes having relatively thin and flexible soles that allow the skateboarder to “feel” the board.
Accordingly, it would be desirable to provide footwear for use in skateboarding that allows the skateboarder to better feel the skateboard and to better control the movement of the board.

BRIEF SUMMARY OF THE INVENTION

Various aspects of the invention relate to footwear having a grooved or slotted sole. More particularly, some aspects of the invention relate to footwear having an outsole with a slot formed therein, to allow flexing of the outsole, particularly in the forefoot region of the footwear. The slot extends, in a generally longitudinal direction, from the medial side to the lateral side of the foot. Having the slot curve across the bottom of the sole from the medial side toward the lateral side enhances the ability for the sole to cup inward, no matter where the pressure is applied during various tricks.
Thus, according to some aspects of the invention, a sole for an article of footwear is provided with an outsole and a slot in the outsole. The article of footwear defines a lateral edge, a medial edge, a forefoot region, a midfoot region and a heel region. The outsole has a thickness, with a longitudinal centerline defined midway between the lateral edge and the medial edge. At least one slot is provided in the outsole. The slot extends, in a substantially longitudinal direction. The slot crosses over the longitudinal centerline in at least one of the forefoot region and the midfoot region. Further, the slot may extend at least substantially over a longitudinal length of the forefoot region.
During use, the slot allows the sole to flex or cup upward (i.e., the central region of the sole in the forefoot region moves upward, away from the ground), while the edges of the sole remain relatively stationary or roll slightly outward.
In other instances, the foot may slide along the skateboard as it also rotates toward the lateral edge of the sole. The slot allows the skateboarder to keep a larger percentage of the sole on the board for a longer time period. This is an improvement over existing skateboarding shoes that tend to have an abrupt transition from having good contact with the board to having little or no contact with the board as the foot slides along the board.
Further, according to an aspect of the invention, the slot extends through the thickness of the outsole. Having a slot extending through the outsole provides a greater degree of flexibility.
According to another aspect of the invention, the sole further includes a midsole attached to the outsole, wherein the midsole includes a groove that at least partially complements the slot in the outsole.
According to even other aspects of the invention, an article of footwear is provided with a sole having a slot that crosses over the longitudinal centerline in at least one of the forefoot region or the midfoot region. The article of footwear may also include a grooved midsole. An article of footwear having a generally longitudinal slot formed in an outsole and a generally longitudinal, complementary groove in the midsole may provide a desired degree of flexibility in the sole for skateboarders.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing Summary, as well as the following Detailed Description, will be better understood when read in conjunction with the accompanying drawings.

FIG. 1 is a lateral side view of an article of footwear having an upper and a sole structure in accordance with aspects of the invention.

FIG. 2 is a perspective view, looking from the bottom, of the article of footwear shown in FIG. 1.

FIG. 3A is a cross section, along line III-III, of the article of footwear shown in FIG. 2, showing the slot extending 100 percent through the thickness of the outsole in accordance with one embodiment.

FIG. 3B is an alternative cross section, along line III-III, of the article of footwear shown in FIG. 2, showing the slot extending partially through the thickness of the outsole in accordance with an alternative embodiment.

FIG. 4 is a bottom plan view of the sole structure of the article of footwear shown in FIGS. 1-3A.

FIG. 5 is a bottom plan view of the sole structure of the article of footwear in accordance with one aspect of the invention.

FIG. 6 is a bottom plan view of the sole structure of the article of footwear in accordance with another aspect of the invention.

FIG. 7 is a bottom plan view of the sole structure of the article of footwear in accordance with a further aspect of the invention.

FIG. 8 is a bottom plan view of the sole structure of the article of footwear in accordance with one aspect of the invention.

FIG. 9 is a bottom plan view of the sole structure of the article of footwear in accordance with even another aspect of the invention.

FIG. 10 is a bottom plan view of the sole structure of the article of footwear in accordance with an aspect of the invention.

FIG. 11 is a bottom plan view of the sole structure of the article of footwear in accordance with even a further aspect of the invention.

FIG. 12 is a bottom plan view of the sole structure of the article of footwear in accordance with another aspect of the invention.

FIG. 13 is a cross section of an article of footwear in accordance with an aspect of the invention.

FIG. 14 is a cross section of an article of footwear in accordance with another aspect of the invention.

FIG. 15 is a perspective end view of a lace in accordance with an aspect of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following discussion and accompanying figures disclose an article of footwear having sole with a slot in accordance with various aspects of the present invention. Concepts related to the slotted sole are disclosed with reference to an article of athletic footwear having a configuration suitable for the activity of skateboarding. The slotted sole is not solely limited to footwear designed for skateboarding, however, and may be incorporated into a wide range of athletic footwear styles, including shoes that are suitable for baseball, basketball, cross-training, football, rugby, soccer, tennis, volleyball, and walking, for example. In addition, a slotted sole according to various embodiments of the invention may be incorporated into footwear that is generally considered to be non-athletic, including a variety of dress shoes, casual shoes, sandals, and boots. An individual skilled in the relevant art will appreciate, given the benefit of this disclosure, that the concepts disclosed herein with regard to the slotted sole apply to a wide variety of footwear styles, in addition to the specific styles discussed in the following material and depicted in the accompanying figures.
An article of footwear 100 is depicted in FIGS. 1-4 as including a sole structure 10 and an upper 20. Upper 20 is secured to sole structure 10 and defines a void for receiving a foot. In one aspect, the sole is a cup sole formed as a single piece.
For purposes of reference in the following material and referring to FIG. 4, sole structure 10 may be divided into three general regions: a forefoot region 11, a midfoot region 12, and a heel region 13. These three regions extend between a front edge 14 and a back edge 15. Forefoot region 11 may further be considered to encompass a ball portion 11 a and a toe portion 11 b. Ball portion 11 a generally extends under the ball region of the foot. Toe portion 11 b generally extends under the toe region of the foot. Although regions 11-13 apply generally to sole structure 10, references to regions 11-13 may also apply specifically to article of footwear 100, upper 20, or an individual component within either sole structure 10 or upper 20.
For further purposes of reference, sole structure 10 includes a longitudinal centerline 16. Longitudinal centerline 16 extends from front edge 14 to back edge 15 and bisects sole structure 10. A medial edge 17 and a lateral edge 18 extend from front edge 14 to back edge 15 along the medial and lateral sides of sole structure 10, respectively. Additionally, longitudinal centerline 16 defines a medial side 17 a and a lateral side 18 a.
With respect to upper 20 and for purposes of reference, upper 20 may include an ankle opening that provides the foot with access to the void within upper 20. As is conventional, upper 20 may also include a vamp area having a throat and a closure mechanism. The closure mechanism may include a lace 25. Other closure or size adjustment mechanisms may be utilized in a conventional manner to modify the dimensions of upper 20 relative the foot, thereby adjusting the fit of footwear 100.
Sole structure 10 is secured to a lower surface of upper 20 and has a structure that includes an outsole 30. Outsole 30 may be formed of a wear-resistant material, such as natural or synthetic rubber or a combination thereof. One particular composite rubber mixture may include approximately 75% natural rubber and 25% synthetic rubber. The synthetic rubber could include a styrene-butadiene rubber. Other suitable polymeric materials for outsole 30 include plastics, such as PEBAX® (a poly-ether-block co-polyamide polymer available from Atofina Corporation of Puteaux, France), silicone, thermoplastic polyurethane, polypropylene, polyethylene, ethylvinylacetate, and styrene ethylbutylene styrene, etc. The material of outsole 30 may also include fillers or other components to tailor its wear, durability, abrasion-resistance, compressibility, stiffness and/or strength properties. Thus, for example, outsole 30 may include reinforcing fibers, such as carbon fibers, glass fibers, graphite fibers, aramid fibers, basalt fibers, etc. Multiple different materials may be used to form outsole 30. The material forming outsole 30 may be textured to impart enhanced traction and slip resistance. Further, outsole 30 may include coatings to enhance traction and slip resistance.
Referring to FIGS. 3A and 3B, in some aspects of the invention, sole structure 10 includes a midsole 40. Midsole 40 is secured to an upper surface of outsole 30. Midsole 40 may be formed of polymer foam material, such as polyurethane or ethylvinylacetate, which compresses to attenuate ground reaction forces during walking, running, or other ambulatory activities. In some embodiments of the invention, the polymer foam material may encapsulate or include various elements, such as a fluid-filled bladder or moderator, which enhances the comfort, motion-control qualities, stability, or ground reaction force attenuation of footwear 100.
Footwear 100 may also include a sockliner 22, which is generally a thin, compressible member that is located within the void in upper 20 and adjacent to a lower surface of the foot to enhance the comfort of footwear 100.
As seen in FIGS. 2-14, sole structure 10 includes a slot 50. Slot 50 is a relatively narrow, elongated feature that extends at least partially through the thickness of outsole 30 (see FIGS. 3A and 3B). As illustrated in FIGS. 4-12, slot 50 crosses over longitudinal centerline 16 at least once. Thus, at least a portion of slot 50 is located on medial side 17 a of sole structure 10 and at least a portion is located on lateral side 18 a. The slot increases the flexibility of the outsole, and thus, increases the flexibility of the entire sole structure 10. Further, the extension of the slot across the centerline provides a cupping action, i.e., the ability of a portion of the sole structure to pull away from the skateboard surface when pressure is applied adjacent the edges of the sole structure 10. Because the upward cupping action releases some of the pressure in the central portion of the sole structure 10, the pressure and gripping action near the edges of the sole structure 10 is increased. This results in improved traction and control of the skateboard. Slot 50 includes a first end 51 and a second end 52.
As shown in FIG. 4 and according to one embodiment of the invention, the entirety of slot 50 may be located within forefoot region 11. Slot 50 extends in a generally longitudinal direction. Further, slot 50 extends at least substantially over the longitudinal length of the forefoot region. In this embodiment, slot 50 extends over more than 50% of the longitudinal length of the forefoot region 11. Indeed, in this embodiment, slot 50 extends over more than 60% of the longitudinal length of the forefoot region 11. The greater the slot length, the more flexible the sole and the more capacity for upward cupping. First end 51 in this illustrated example structure 10 is located on medial side 17 a within toe portion 11 b and second end 52 is located on lateral side 18 a within ball portion 11 a. Slot 50 crosses over longitudinal centerline 16 within toe region 11 b. In this embodiment, slot 50 is illustrated with a substantially constant width.
As shown in FIGS. 5 and 6, and according to other embodiments of the invention, slot 50 may extend through portions of forefoot region 11 and midfoot region 12. As best shown in FIG. 5, within toe portion 11 b, slot 50 extends from first end 51 located in medial side 17 a and crosses over longitudinal centerline 16 into lateral side 18 a. In the embodiment of FIG. 5, slot 50 extends over more than 70% of the longitudinal length of forefoot region 11. Slot 50 follows a concave curve (relative to medial side 17) within ball portion 11 a. Within midfoot region 12, slot 50 crosses back over longitudinal centerline 16 and ends at second end 51 located in medial side 17 a. As best shown in FIG. 6, first end 51 in this example structure 10 is located within ball portion 11 a (in lateral side 18 a) and second end 52 is located within midfoot region 12 (in medial side 17 a). Slot 50 crosses over longitudinal centerline 16 within midfoot region 12.
As shown in FIGS. 7 and 8, and according to further embodiments of the invention, slot 50 extends through portions of forefoot region 11, midfoot region 12 and heel region 13. Thus, in one embodiment as best shown in FIG. 7, first end 51 is located within toe portion 11 b (in medial side 17 a) and second end 52 is located within heel region 13 (also in medial side 17 a). Slot 50 crosses over longitudinal centerline 16 twice, once in toe portion 11 b and again in midfoot region 12. As best shown in FIG. 8, first end 51 in this example structure 10 is located within toe portion 11 b (medial side 17 a) and second end is located within heel region 13 (lateral side 18 a). In FIG. 8, slot 50 doubles back on itself, generally following the outer contour of outsole 30 in heel region 13. In this embodiment, the slot 50 crosses over longitudinal centerline 16 three times.
As shown in FIG. 9, and according to one embodiment of the invention, slot 50 extends from front edge 14 to medial edge 17 of outsole 30. In this embodiment, first end 51 and second edge 52 of slot 50 are open ends, i.e., the ends are not closed. Thus, outsole 30 may be formed as two separate pieces, 30 a, 30 b. As shown in FIG. 10, one end of slot 50, e.g., first end 51, may be an open end, while the other end, e.g., second end 52, may be a closed end.
Further, outsole 30 may include more than one slot. Thus, as shown in FIG. 11, a first slot 50 a may be located within forefoot region 11 and a second slot 50 b may extend over portions of forefoot region, 11 midfoot region 12 and heel region 13. A ligament or other connecting element 58 may extend from one portion of outsole 30 to another portion of outsole 30, thereby separating first slot 50 a from second slot 50 b. Connecting element 58, which may be formed integrally with outsole 30, may be formed with the full thickness of the outsole or it may be formed by a reduced thickness.
In another embodiment, as shown in FIG. 12, outsole 30 may include a plurality of slots 50 a, 50 b and 50 c. Further, the slots need not be aligned. For example, slots 50 a and 50 c are generally aligned along a common elongate axis, while slot 50 b is offset from this common elongate axis.
Slot 50 may be linear, curvilinear, or composed of a combination of either linear or curvilinear segments. In one embodiment, the slot depth is greater than 60% of the thickness of the bottom layer of outsole 30. The greater the slot depth, the more flexible the sole. In other embodiments, the depth of the slot could be greater than 70% of the thickness of outsole 30, preferably greater than 80%, more preferably greater than 90%, and even more preferably a depth of 100% (i.e. a through thickness slot). Moreover, slot 50 need not have a constant depth.
Because of the inward cupping of the outsole, it may be desirable to control the width of the slot in the outsole to within a certain range. If the width is too small, it would interfere with the cupping action (i.e. the edges of the slot might pinch against one another and inhibit complete cupping). If, on the other hand, the width is too large, the slot might catch on the board or other edges as the foot moves and slides along the board during use. In such case, the thickness of the slot is preferably designed to prevent or minimize interference between the two sides of the slot during the cupping action and also to prevent or minimize the edges of the slots from catching on the skateboard or other surfaces. In one embodiment, the slot width is approximately 7 mm. In other embodiments, the width of the slot could range from approximately 4 mm to approximately 10 mm, preferably from slot 4 mm to approximately 8 mm, and more preferably from approximately 6 mm to approximately 7 mm. Further, slot 50 need not have a constant width. It may be particularly desirable to control the width of the slot when the slot extends through the thickness of outsole 30 and particularly when the slot extends through the thickness in the forefoot region.
According to another aspect of the invention as shown in FIGS. 13 and 14, midsole 40 has a channel or groove 42 that complements at least some portion of slot 50. By forming a groove 42 in the midsole 40, the overall flexibility of the sole structure is further increased. Thus, as best shown in FIG. 13, midsole 40 has a groove 42 that extends partially through the thickness of midsole 40. As shown in FIG. 13, the edges of groove 42 are approximately aligned with the edges of slot 50. As shown in FIG. 14, the edges of groove 42 are generally not aligned with the edges of slot 50. The width of groove 42 could be less than, equal to, or greater than the width of slot 50. Further, the width and/or depth of groove 42 may vary along its length. The length of groove 42 need not be coextensive with the length of slot 50. Further, multiple grooves may be provided in midsole 40. By varying the length, the thickness, or the width of groove 42, the ultimate flexibility of the sole structure may be tailored for specific skateboarding styles.
Another aspect of the footwear relates to the upper. The upper, or a portion of the upper, may be made from a material capable of “gripping” the board. This “gripping” capability may be particularly desirable on the lateral forefoot side of the shoe. In one embodiment, enhanced gripping may be achieved by providing a relatively soft durometer rubber (or like material) on the upper. In another embodiment, enhanced gripping may be achieved by providing a textured surface.
Thus, referring back to FIG. 1, upper 20 or an upper portion 20 a may be provided with a material that has enhanced “gripping” properties. For example, upper portion 20 a may be formed from a relatively soft durometer rubber (or like material). For example, the softer durometer rubber may have a hardness of 60 to 75 Shore A, possibly of 60 to 70 Shore A, and possibly of 64 to 70 Shore A. The placement, boundaries and shape of upper portion 20 a may vary from that shown in FIG. 1. In another embodiment, enhanced gripping may be achieved by providing a textured surface on upper 20 or upper portion 20 a. Examples of possible textured surfaces are disclosed in Applicant's co-pending application, “Skateboard Shoe with Textured Surface,” Ser. No. 11/626,831, Publication No. 2007/0256328, which is hereby incorporated by reference in its entirety. Upper portion 20 a may be formed integrally with the remainder of upper 20. Alternatively, upper portion 20 a may be stitched, glued, sprayed or coated, or otherwise attached to the remainder of upper 20. If desired, the gripping portion 20 a may be provided as a plurality of separate islands, dots, strips, or the like of soft material that provides the enhanced gripping properties at the desired locations.
Further, with respect to another aspect of the invention, at least a portion of the outsole may be provided with a grip enhancing component. The grip enhancing component may provide improved gripping properties as the foot moves and rolls along the board, while the base portion of the outsole may provide long term durability and wear resistance. Further, the grip enhancing component may allow a larger area of the edge to maintain contact with the board as the foot moves and rolls along the board.
Thus, with respect to this aspect of the invention and referring to FIGS. 1 and 3A, at least a portion 30 a of outsole 30 may be provided with a material that has enhanced “gripping” properties. Thus, for example, a relatively soft rubber or rubber-like component may be provided in portion 30 a of outsole 30. In another example, a relatively soft thermoplastic material, such as a thermoplastic polyurethane (TPU) may be provided in portion 30 a. In one embodiment, a softer durometer rubber may form an outer layer (e.g., a rubber having a hardness of 60 to 75 Shore A, possibly of 60 to 70 Shore A, and possibly of 64 to 70 Shore A), with a harder durometer rubber forming an inner layer (e.g., a rubber having a hardness of 70 to 90 Shore A, and possibly of 75 to 88 Shore A). As shown in FIGS. 1 and 3A, the enhanced gripping material may be provided in the forefoot region 11 of outsole 30. In particular, the softer rubber may be provided on at least a portion of the side walls of outsole 30 in the forefoot region 11. The enhanced gripping material may be co-molded to outsole 30. Optionally, the enhanced gripping material may be adhesively or otherwise attached to outsole 30.
In even another aspect of the invention, the article of footwear may be laced. The laces may include reinforcing fibers. Further, the lace aglets may include fibers or whiskers.
Thus, according to this aspect and referring to FIGS. 1, 2 and 15, the article of footwear may be laced. Laces 25 may include reinforcing fibers 27. For example, laces 25 may contain greater than approximately 1% by weight of aramid fibers (e.g. Kevlar®). As another example, the laces may include greater than approximately 3% by weight of aramid fibers, greater than 10%, or even greater than 20%. As even another example, the laces may include upwards of approximately 30% by weight of aramid fibers. Fibers 27 may be woven, braided, molded, co-extruded, etc. into the laces. Further, in even another aspect, the lace aglets 27 may include fibers or whiskers of graphite, carbon, glass, aramid, basalt, etc. In one embodiment, the aglets 27 include aramid fibers.
While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art, given the benefit of this disclosure, will appreciate that there are numerous variations and permutations of the above described systems and techniques that fall within the spirit and scope of the invention as set forth above. Thus, for example, a wide variety of materials, having various properties, i.e., flexibility, hardness, durability, etc., may be used without departing from the invention. All examples, whether preceded by “for example,” “such as,” “including, or other itemizing terms or followed by “etc.,” are meant to be non-limiting examples, unless otherwise stated or obvious from the context of the specification.

Claims

1. A sole for an article of footwear, the article of footwear having a lateral edge, a medial edge, a forefoot region, a midfoot region and a heel region, the sole comprising:

an outsole having a thickness, with a longitudinal centerline defined midway between the lateral edge and the medial edge; and

at least one slot in the outsole,

wherein the slot extends in a substantially longitudinal direction, and

wherein the slot crosses over the longitudinal centerline in at least one of the forefoot region and the midfoot region.

2. The sole of claim 1, wherein the slot crosses the centerline in the forefoot region.

3. The sole of claim 1, wherein the slot crosses the centerline in a toe portion of the forefoot region.

4. The sole of claim 1, wherein the slot extends over more than approximately 50 percent of a longitudinal length of the forefoot region.

5. The sole of claim 1, wherein the slot extends over more than approximately 60 percent of a longitudinal length of the forefoot region.

6. The sole of claim 1, wherein the slot extends over more than approximately 70 percent of a longitudinal length of the forefoot region.

7. The sole of claim 1, wherein the slot further extends into the midfoot region.

8. The sole of claim 7, wherein an end of the slot is located in the toe portion.

9. The sole of claim 1, wherein the slot crosses the centerline in the midfoot region.

10. The sole of claim 3, wherein an end of the slot is located in the heel region.

11. The sole of claim 1, wherein the outsole is a cup sole.

12. The sole of claim 1, wherein the outsole includes a material having a Shore A hardness in a range of approximately 60 to approximately 75.

13. The sole of claim 1, wherein, in the forefoot region, at least a portion of the slot has a depth that extends at least 90 percent through the thickness of the outsole.

14. The sole of claim 1, wherein, in the forefoot region, at least a portion of the slot has a depth that extends 100 percent through the thickness of the outsole.

15. The sole of claim 10, wherein, in the forefoot region, at least a portion of the slot has a width that ranges from approximately 4 mm to approximately 10 mm.

16. The sole of claim 10, wherein, in the forefoot region, at least a portion of the slot has a width that ranges from approximately 6 mm to approximately 7 mm.

17. The sole of claim 1, wherein, in the forefoot region, the slot defines a concave curve relative to the medial edge.

18. The sole of claim 1, further comprising:

a midsole attached to the outsole,

wherein the midsole includes a groove that at least partially complements the slot in the outsole.

19. An article of footwear comprising:

the sole according to claim 1; and

an upper attached to the sole.

20. The article of footwear of claim 19, wherein the slot crosses the centerline in the forefoot region.

21. The article of footwear of claim 19, wherein the slot crosses the centerline in a toe portion of the forefoot region.

22. The article of footwear of claim 19, wherein the slot extends over more than approximately 50 percent of a longitudinal length of the forefoot region.

23. The article of footwear of claim 19, wherein the slot extends over more than approximately 70 percent of a longitudinal length of the forefoot region.

24. The article of footwear of claim 19, wherein the slot further extends into the midfoot region.

25. The article of footwear of claim 24, wherein an end of the slot is located in the toe portion.

26. The article of footwear of claim 19, wherein the slot crosses the centerline in the midfoot region.

27. The article of footwear of claim 26, wherein an end of the slot is located in the heel region.

28. The article of footwear of claim 19, wherein the outsole is a cup sole.

29. The article of footwear of claim 19, wherein, in the forefoot region, at least a portion of the slot has a depth that extends 100 percent through the thickness of the outsole.

30. The article of footwear of claim 29, wherein, in the forefoot region, at least a portion of the slot has a width that ranges from approximately 4 mm to approximately 10 mm.

31. The article of footwear of claim 19, wherein the outsole includes a material having a Shore A hardness within a range of approximately 60 to approximately 75.

32. The article of footwear of claim 19, wherein the upper includes a portion in the forefoot region having a Shore A hardness of approximately 60 to approximately 75.

33. A sole for an article of footwear, comprising:

an outsole having a toe portion, a ball portion and a midfoot region, the outsole further having a medial side and a lateral side; and

a slot located in the outsole, the slot having a first end, a second end and an elongate portion therebetween,

wherein the first end of the slot is located on the medial side in the toe portion,

wherein at least a section of the elongate portion of the slot is located on the lateral side of the ball portion, and

wherein at least another section of the elongate portion of the slot is located in the medial side in the midfoot region.

34. The sole of claim 33, wherein at least a portion of the slot extends through the thickness of the outsole.

35. The sole of claim 33, further comprising:

a midsole having a groove that has at least portions that generally correspond to the slot.

36. A lace for an article of footwear comprising:

aramid fibers.

37. The lace of claim 36, having approximately 1 percent to approximately 30 percent by weight of aramid fibers.