Patent Application
20140310981
Stabilization of the body's coronal, sagittal, and transverse planes is important to efficient, injury-free running Most athletic shoes support a person's weight with a bed of foam, which is a soft and unstable platform that allows a runner's foot to sink or settle into the shoe upon contact with the ground. Uneven sinking or settling of the foot reduces stability, creates an unnecessary strain on the foot, leg and torso muscles, and masks afferent feedback to the central nervous system. Additionally, a foam bed may encourage uneven weight distribution across the bones of the foot. Such uneven weight distribution may, over time, create depressions in the foam that result in injuries due to misalignment of the bones and excessive stress on connective tissues.
Implementations described herein may be utilized to address at least one of the foregoing problems by providing an article that reduces damping of afferent feedback to the central nervous system when a compressive weight is placed thereon. In one implementation, the article includes a cushioning and support layer to cushion and support a user's foot and an afferent feedback and biomechanical support plate positioned between the cushioning and support layer and the user's foot. Such a plate may help a runner to initiate stability as they contact and load their foot and allow for a more evenly distributed compression of the cushioning and support layer.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. These and various other features and advantages will be apparent from a reading of the following Detailed Description.
A further understanding of the nature and advantages of the present technology may be realized by reference to the figures, which are described in the remaining portion of the specification.
Recent studies have shown that a “natural running” form can help to reduce the frequency and severity of some common running injuries. “Natural running” refers to a form of running that a habitually barefoot runner adopts to reduce loading rates and protect the foot from excessive impact while moving quickly and efficiently. A runner practicing natural running form strikes the ground close to a point under the body's center of gravity with a relaxed foot rather than over striding (e.g., landing with the foot in front of the runner's center of gravity) with an aggressively dorsiflexed ankle In an efficient gait cycle, the runner lands lightly with a relaxed foot and avoids exaggerated joint positions and excessive use of muscular force.
Afferent feedback is the body's mechanism for sensing the environment. During the contact phase of the gait cycle, afferent neurons carry nerve impulses toward the central nervous system. Conventional running shoes impede the ability of the central nervous system to receive such feedback by dampening sensory input to the foot. The technology disclosed herein reduces damping of afferent feedback to the runner by providing a structured support surface that causes the runner's central nervous system to transmit sensory input from the bottom of the foot to the user's central nervous system. Such a plate assists in stabilization during the contact and stance phase of the gait cycle, which helps the runner to respond effectively to the running surface, reduce loading rates, and reduce the risk of injury.
The described technology may also be useful for providing afferent feedback to areas of the body other than feet, such as the hands. Thus, this technology is also contemplated for use in gloves and other active wear for use during physical activities (e.g., running, biking) when enhanced afferent feedback is desirable.
The sole construction 100 includes a cushioning and support layer 110 (i.e., a midsole layer) including an upper surface (e.g., a foot-facing surface) that is sized and shaped to receive and substantially underlie the foot. The cushioning and support layer 110 is a layer that cushions and supports a user's foot. The cushioning and support layer 110 may be composed of a variety of materials such as ethylene-vinyl acetate (EVA), or other foam or soft, pliable material. In other implementations, an elastomeric viscous foam, gel, or other flexible framework may be used.
The sole construction 100 further includes an afferent feedback biomechanical support plate 108 adjacent to the foot-facing surface of the cushioning and support layer 110 and extending longitudinally from the ball of the foot (e.g., underlying the metatarsal bones in the forefoot region 102) through the hindfoot region 106. The afferent feedback biomechanical support plate 108 may laterally span some or substantially the entire width of the sole construction 100. In various implementations, the afferent feedback biomechanical support plate 108 underlies or substantially underlies one or more of the hindfoot region 106, the midfoot region 104, the forefoot region 102, and the toe region 112. Additionally, more than one afferent feedback biomechanical support plate 108 may be included in a single shoe sole.
In operation, the afferent feedback biomechanical support plate 108 helps a runner to initiate stability when landing in the midfoot area 104 of the shoe. When the runner's midfoot contacts the afferent feedback biomechanical support plate 108, afferent feedback is provided to the central nervous system. Such feedback allows the runner's midfoot and/or heel to quickly “lock” into place and stabilize. In one implementation, the afferent feedback biomechanical support plate remains substantially planar even when under load during the contact and stance phase of the gait cycle. The afferent feedback biomechanical support plate 108 above the cushioning and support layer 110 encourages even weight distribution across the cushioning and support layer 110, and protects the cushioning and support layer 110 from deterioration, including wear caused by uneven weight distribution.
The afferent feedback biomechanical support plate 108 may be constructed of a stiff, lightweight material with sufficient elasticity to permit torsional compliance and movement, although the degree of such movement permitted may vary according to specific design criteria. Suitable material choices for the afferent feedback biomechanical support plate 108 include without limitation solid ethylene-vinyl acetate (EVA), thermal polyurethane, rubber, synthetic rubber, DuPont Hytrel™, and carbon-fiber.
The hardness value of the afferent feedback and biomechanical support plate 108 is greater than a hardness value of the cushioning and support layer 110. Although a variety of hardness values are contemplated, the afferent feedback and biomechanical support plate 108 has a hardness value of at least 45 shore D. In one implementation, the hardness of the afferent feedback biomechanical support plate 108 is about 65 shore D. In the same or another implementation, the hardness of the cushioning and support layer 110 is at least 45 shore D. The afferent feedback biomechanical support plate 108 may vary in thickness according to design criteria, such as to allow for more or less flexibility along lateral and longitudinal axis of the sole construction 100. In one implementation, the afferent feedback biomechanical support plate 108 is constructed of solid EVA and the cushioning and support layer 110 is constructed of an EVA foam.
The afferent feedback biomechanical support plate 108 may have a substantially even (i.e., non-variable) thickness, or a variable thickness. The thickness of the afferent feedback biomechanical support plate 108 may range, for example, from between about one and about three millimeters. In one implementation, the afferent feedback biomechanical support plate 108 is about 2 mm thick and the cushioning and support layer 110 is greater than or substantially equal to 6 mm thick. In another implementation, the afferent feedback biomechanical support plate 108 is about 1.2 mm thick and the cushioning and support layer 110 is greater than or substantially equal to 6 mm thick.
In yet another implementation, the thickness of the afferent feedback biomechanical support plate 108 is variable along its length and/or width to provide stiffer or firmer support under different regions of the runner's foot. For example, the afferent feedback biomechanical support plate 108 may be thinner along the lateral side (e.g., outside) of the midfoot 104 and thicker along the medial side (e.g., inside, along the arch) of the midfoot 104 to provide for additional protection against late-stage pronation. Alternatively, the afferent feedback biomechanical support plate 108 may be thicker along the lateral side of the midfoot 104 and thinner along the medial side of the midfoot 104 to provide for additional stability under the midfoot and protection against pronation and supination. In one implementation, the foam plate 108 has a thickness of about 0.9 mm on a first side (e.g., a lateral or medial side), and a thickness of about 1.5 mm on an opposite side (e.g., the medial or lateral side). In at least one implementation, the afferent feedback biomechanical support plate 108 is positioned such that it is closer to a foot-facing outer surface of the sole construction 100 than to a ground-facing outer surface of the sole construction 100.
In yet another implementation, the thickness of the afferent feedback biomechanical support plate 108 is substantially non-variable and the afferent feedback biomechanical support plate 108 has regions of increased density with respect to other regions.
The length and width of the afferent feedback biomechanical support plate 108 may vary according to design criteria. In various implementations, the afferent feedback biomechanical support plate 108 underlies one or more than one of the toe region 112, the forefoot region 102, the midfoot region 104, or the heel region 106. For example, the afferent feedback biomechanical support plate 108 may underlie the heel region 106 and a portion of the midfoot region 104, but exclude the forefoot region 102. In at least one implementation, the afferent feedback biomechanical support plate 108 is incorporated into a removable foot bed that can be inserted into and removed from a shoe by a user.
The afferent feedback biomechanical support plate 108 may also include one or more cutout areas (i.e., apertures or holes) to allow for engagement of one or more actuators of the sole construction 100. Such actuators may be positioned under one or more primary pressure points of the foot, such as under the heel, midfoot, forefoot, or toes. The sole construction 100 includes an actuator 114 in the heel region 106, substantially underlying the center of the runner's heel. The afferent feedback biomechanical support plate 108 includes a hole (not shown) sized and shaped to receive the actuator 116 to permit contact between the actuator and the runner's heel during a mid-stance or contact phase of the gait cycle.
In one implementation, the actuator is capable of storing some of the runner's kinetic energy as potential energy and returning such kinetic energy to the runner as the runner removes his or her weight from the heel region 102 of the shoe.
The sole construction 100 also includes an upper 124 (i.e., fabric forming the top of the shoe) attached to a stability layer 122 that underlies and contacts the runner's foot when the foot is in the shoe. The upper 124 may be attached to the stability layer 122 in a variety of ways such as via stitching, adhesives, etc. For example, the upper 124 may be attached to the stability layer 122 by stitching around the periphery of the stability layer 122. Other attachment mechanisms may also be employed to bond the upper 124 to the stability layer 122.
The stability layer 122 may be foam (e.g., EVA), rubber, fiberboard (e.g., Strobel Board) or other flexible material. In one implementation, the stability layer 122 is a Strobel Board about 2 mm thick, which is sewn to the upper 124. Other methods of attachment may also be employed to bond the stability layer 122 to the cushioning and support layer 110.
The sole construction 100 further includes an abrasive-resistant underlayer 126 that contacts the ground when the shoe is in use. Other implementations may include layers in addition to or in lieu of those layers (e.g., the abrasive-resistant underlayer 126, the cushioning and support layer 110, and the stability layer 122) illustrated in
In various implementations, one or more layers may also be interleaved between the user's foot and the afferent feedback and biomechanical support plate 108.
In
The afferent feedback biomechanical support plate 208 provides pressure below the metatarsal bones of the foot. In particular, the afferent feedback biomechanical support plate 208 provides pressure below the base of the fifth (e.g., lateral side 214) metatarsal where a high-speed runner typically lands. This pressure allows the runner to lock the hindfoot and ankle when the midfoot strikes the ground in the midfoot region 204 of the sole construction 200, allowing for quick stabilization and efficient elastic recoil and push-off from the ground. Because the afferent feedback biomechanical support plate 208 does not underlie the hindfoot region 206 of the foot, the implementation of
The perforations are formed across substantially the entire length and width of the afferent feedback biomechanical support plate 308 to reduce the weight of the sole construction 300 without substantially reducing the stability and afferent feedback provided by the afferent feedback biomechanical support plate 308. In another implementation, the afferent feedback and biomechanical support plate 308 has perforations formed across less then all of the plate. Although the afferent feedback biomechanical support plate 308 could be implemented in a variety of specialty shoe types (running, walking, cross-training, etc.), the implementation of
In yet another implementation, small perforations are formed across some or all of the afferent feedback biomechanical support plate 308 to provide increased torsional flexibility (i.e., flexibility along a longitudinal axis 320). For example, hollow perforations may be formed on the lateral side 314 of the midfoot region 304 but not the medial side 316 of the midfoot region 304 (e.g., to reduce or prevent pronation). Alternatively, hollow perforations may be formed on the medial side 316 of the midfoot region 304 rather than the lateral side 314 of the midfoot region 304 (e.g., to reduce or prevent supination).
In the heel region 406, the afferent feedback biomechanical support plate 408 includes a cutout 422 (e.g., a hole) that may underlie the center of a runner's heel to engage the runner's heel bones with a heel actuator (not shown) upon contact with the ground. In particular, the cutout 422 may underlie the calcaneus bone of the runner's foot. Although the cutout 422 illustrated is oval shaped, a variety of shapes are contemplated including without limitation circular, triangular, rectangular, or non-traditional shapes. The actuator may be configured to absorb, store, and return energy to the runner. The sole constructions of
In the implementation of
The width of the afferent feedback biomechanical support plate 408 overlying the waist 418 of the sole construction 400 is relatively narrow as compared to a width 416 of the forefoot region 402 and a width 420 of a hindfoot region 406. Consequently, the sole construction 400 provides for more torsional flexibility than a sole construction with a wider afferent feedback biomechanical support plate 408 of substantially the same thickness. In other implementations, the thickness of the afferent feedback biomechanical support plate 408 and/or the width of the waist portion 418 of the afferent feedback biomechanical support plate 408 is selectively varied to provide for less torsional flexibility (such as in a stability running shoe) or more torsional flexibility (such as in a neutral running shoe). For example, torsional flexibility may be selectively increased by decreasing the thickness of the afferent feedback biomechanical support plate 408 or by tapering the width of the afferent feedback biomechanical support plate 408 around the waist 418 with respect to the portions of the afferent feedback biomechanical support plate 408 underlying the metatarsal and/or heel bones of the foot. Alternatively, torsional flexibility of the sole construction 400 can be reduced by increasing the thickness of the afferent feedback biomechanical support plate 408 and/or the width of the afferent feedback biomechanical support plate around the waist 418.
The sole construction 500 also includes a cushioning and support layer 510. In one implementation, the sole construction 500 is a single-piece insert (e.g., a removeable foot bed) that a user can insert into a compatible athletic shoe, glove, or other article of clothing.
The plates with articulated regions may be designed so as to provide for flexibility between each of the articulated regions. For instance, each of the articulated regions of the midfoot plate 518 and/or the forefoot plate 516 may be substantially separated from one another, such as via one or more slits between each of the articulated regions. In the same or another implementation, the regions are separated from one another by region boundaries of decreased density as compared to the density at the center of each articulated region. In yet other implementations, different plates or different regions within a single plate may be raised up or elevated to different heights with respect to the underside (i.e., the ground-facing side) of the sole construction 500.
A sole construction may include one or more articulated plates and/or one or more non-articulated plates. The non-articulated plates may be, for example, the same or similar to the afferent feedback and biomechanical stability plates illustrated in
Material of the afferent feedback biomechanical support plate 708 has been removed from an area 712 in the midfoot region 704 to reduce the total weight of the shoe and provide for increased torsional flexibility. Although the shape of the area of removed material is that of an “x”, a variety of other shapes are contemplated to achieve the same or similar effect.
The cushioning and support layer 710 also includes a cavity 716 underlying the metatarsal bones of the foot. The cavity 716 is sized and shaped to receive a number of metatarsal actuators (not shown). The metatarsal actuators may be configured to absorb, store, and return energy to the runner. One or more additional layers may be formed between the actuators (not shown), afferent feedback biomechanical support plate 708, and an upper (i.e., fabric forming the top of the shoe)(not shown).
The sidewalls 812 and 814 of the afferent feedback biomechanical support plate 808 form an edge with the foot-facing surface of the afferent feedback biomechanical support plate 808 on both a medial side and a lateral side of the sole construction 800. Specifically, the sidewalls 812 and 814 wrap around a portion of the forefoot region 802 to provide additional stability. In particular, the sidewalls 812 and 814 may reduce or prevent lateral or medial movement and breakdown. Additionally, the sidewalls may reduce compression and breakdown of the foam cushioning and support layer 810 and may extend the effective life of the shoe.
In another implementation, the sidewalls 812 and 814 wrap around some of or substantially the entire the midfoot region 804 in addition to or in lieu of wrapping around some or all of the forefoot region 802. In yet another implementation, the afferent feedback biomechanical support plate 808 has sidewalls that wrap around some or substantially the entire heel region 806.
A second providing operation 910 provides an afferent feedback biomechanical support plate between the cushioning and support layer and the user's foot to assist transmission of sensory input from the ground to an area of the user's foot during the impact event. The afferent feedback biomechanical support plate may be a substantially rigid plate adjacent to the foot-facing surface of the cushioning and support layer. In one implementation, the afferent feedback biomechanical support plate extends longitudinally along an area under the midfoot (e.g., an area underlying at least one of a cuneiform bone, the cuboid bone, or the navicular bone).
A third providing operation 915 provides a stability layer to underlie and contact the user's foot during the impact event. A fourth providing operation 920 provides an upper (see, e.g., the compliant upper 124 illustrated in
A force application operation 925 applies a force to a ground-facing surface of the afferent feedback biomechanical support plate during the impact event. The afferent feedback biomechanical support plate distributes the force across an area of the user's foot overlying the afferent feedback biomechanical support plate. In one implementation, the afferent feedback plate remains substantially planar during the impact event. In response to the force, the user's central nervous system provides afferent feedback to the user's cerebellum, which allows the user to quickly stabilize.
The above specification, examples, and drawings provide a complete description of the structure and use of exemplary implementations of the invention. Since many implementations of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended. Furthermore, structural features of the different implementations may be combined in yet another implementation without departing from the recited claims.
