HEELLESS ATHLETIC SHOE
A grid for selecting an appropriate embodiment of an athletic shoe having an upper and a multiple part sole forming an interior volume for receiving an individual's foot. The multiple part sole comprises an inner sole for engaging the plantar surface of the foot, a midsole attached to the exterior of the inner sole and substantially coextensive with the inner sole, and an outer sole attached to the midsole. The outer sole has a first portion extending from the toe of the shoe to a position beneath the foot selected according to the intended use of the shoe, and has a second contiguous portion extending from the selected position to the heel of the shoe, the first portion providing a landing surface for the shoe and the second portion being relatively thin as compared to the first portion thereby promoting proper posture and gait of the wearer.
Field of the Invention
This invention generally relates to footwear and more particularly to shoes for use in athletics and rehabilitation that are tailored for a specific activity and a level of the wearer's expertise for that activity.
Description of Related Art
Shoes suited for physical activities, such as running, jogging, brisk walking, aerobic exercise and the like which involve stepping and landing on an individual's feet are well known. Generally these activities are characterized by suspension and landing of the foot. In such physical activities the individual's foot acts as a shock absorber upon landing, a support member during the period between landing and stepping off, and a spring for propelling, launching, or stepping from the surface such as the ground. Despite many advances in the design and construction of athletic shoes, injuries incurred during such activities continue to be widespread. Such injuries include heal spurs, plantar fascia, shin splints, and stress fractures of the sesamoid bones and head of the metatarsal bones, as well as metatarsalgia. Other musculoskeletal injuries that can result from these physical activities include posterior compartment syndromes, calf reaction syndromes, and various knee, hip, back and scapula problems. Frequently it is the way an individual lands and then steps off that leads to these injuries. In many cases inadequacies of the shoes worn by the individual are a significant contributing factor.
The vast majority of walkers, runners and joggers land heel first on the ground and then push off with the forefoot. However, during the heel landing the Tibialis Anterior, Extensor Digitorum Longus, Extensor Halluces, and Peroneus Tertius place the foot in dorsiflexion. This foot position minimizes the natural shock absorbing capacity of the foot and often leads to the previously discussed injuries.
Forefoot landings, as opposed to heel landings, have proven to be the most efficient landing pattern during physical activities that involve such stepping off and landing. During forefoot landings, the landing forces are applied generally to the dynamic front part of the foot, or forefoot, comprising the toes and the ball of the foot simultaneously. The intrinsic muscles of the foot and the skeletal structure including the gastrocnemius, Soleus, Plantaris, Tibialis Posterior, Flexor Halluces, Peroneus Longus and Brevis place the arch of the foot in a proper attitude to act as a shock absorbing spring as the forefoot impacts a support surface. Moreover, stepping off from the forefoot without initial heel contact tends to increase efficiency as there is no effort expended to roll the foot from the heel to the toe. Forefoot landings also reduce the strain on the musculoskeletal structure. However, individuals also must consciously attempt to land on the forefoot. Frequently they revert to a heel landing when they become fatigued or otherwise distracted or preoccupied.
To overcome the injuries associated with heel landings, makers of various types of athletic shoes generally pad the heel to provide some shock absorption. While such padding does reduce shock somewhat, the impact to the heel can still be in the range of three or more times the individual's weight during jogging. Consequently, even highly padded heels do not provide a sufficient absorption to reduce the number of injuries to individuals. That is, reasonable levels of padding cannot substitute for the shock absorbing system in an individual's forefoot.
U.S. Pat. No. 5,694,706 (1997) to Penka for a heelless athletic shoe which enhances forefoot landing during various physical activities, inhibits heel landings, enhances an individual's performance and does not cause the foot to undergo unnecessary and potentially dangerous dorsiflexion from the step off to the pre-landing phase. Penka also provides a shoe that is adapted for use during rehabilitation from injuries caused by heel-to-toe landing patterns and encourages pre-disposition of the foot for landing on and immediate stepping off from the forefoot while not placing undue tension on the Gastrocnemius-Soleus muscle and the Achilles tendon.
Such a shoe has an upper and a multiple part lower sole forming an interior volume for receiving an individual's foot. The multiple part sole comprises an inner sole, a midsole and an outer sole. The inner sole engages the plantar surface of the foot. The midsole is relatively rigid and attaches to the exterior of the inner sole to be coextensive with at least a portion of the forefoot and supports the plantar surface of the foot. The front or proximal section of the outer sole may have a different thickness according to different embodiments of this invention which underlies at least a portion of the forefoot and a contiguous rear portion for underlying the heel. The front section provides a landing surface for the shoe. The rear portion is thinner than the landing surface whereby an exterior surface of the rear portion is elevated relative to the landing surface thereby to prevent heel landings.
However, the prior art does not specify the depth or thickness and the length of the recess area appropriate for different individuals who engage in different types of activities at different levels of skill. This lack of specification is leading to a new trend of musculoskeletal injuries such as calf reaction, plantar fascia, metatarsalagia and the cuboid syndromes. To help prevent these injuries, the recess area of the heel must be clearly defined in depth, length and thickness of the sole of the shoe.
Therefore, it is the object of this invention to disclose a heelless shoe grid based on the type of activity or sport the wearer intends to undertake, the state of individual's physical conditioning, and the skill level of the wearer in the chosen activity.
Another object of the invention is to enhance the performance of the wearer of such a shoe in their activity of choice.
Still another object of the invention is to provide previously unavailable embodiments for an athletic shoe or shoes suited for rehabilitation of individuals with various types of injuries or conditions.
In accordance with this invention an embodiment of a heelless shoe has an upper including a toe portion, a midsection and a rear portion and a multiple part sole forming an interior volume for receiving an individual's foot. The multiple part sole comprises an inner sole for engaging the plantar surface of the foot, a midsole having an inner surface attached to the exterior of the inner sole to be substantially coextensive with the inner sole, the midsole having an outer surface, and an outer sole attached to the outer surface of the midsole intermediate the inner and outer soles. The outer sole has a first portion extending from the proximal end of the shoe to a position under the foot selected according to an intended use of the shoe and a second contiguous portion extending from the selected position to the distal or rear portion of the shoe. The first portion of the outer sole provides a landing surface for the shoe and the second, relatively thin portion as compared to the first portion thereby inhibiting landings on the heel for different embodiments of the shoe and generally promoting an appropriate posture or gait for the wearer while performing the motions involved in the selected activity.
The various objects, advantages and novel features of this invention will be more fully apparent from a reading of the following detailed description in conjunction with the accompanying drawings in which like reference numerals refer to like parts, and in which:
As shown in
The upper 11 as depicted in
With reference to
Still referring to
The spacing, or recess depth D in
In accordance with this invention a range of values for a length, L, of the outer isole 20 and a recess depth D suited to a typical individual for use during participation in certain common activities define different values.. In the various embodiments of this invention, the length L represents the distance from the front end 36 of the toe box 13 rearward to the beginning 55 of the recessed portion 28 of the outer sole 20. LT represents the full length of the shoe 10 from the tip of the toe 36 to the back of the heel 57.
As depicted in
As will be apparent to one skilled in the art, the area of the forefoot that bears the weight of the body during landing is closer to the front of the forefoot in an activity such as dance (L=f) than, for example, basketball (L=b or c). In an activity such as walking (L=a or b), the landing surface 22 is still longer since the weight of the body is typically pressing further back towards the heel of the foot during landing and the greater length of the landing surface 22 provides for cushioning of the foot from landing through transfer of the body weight forward during motion through stepping off while preventing potentially harmful heel strikes.
Still referring to
The different lengths L of the landing surface 22 correspond to anatomical features of the individual's foot inside the shoe as illustrated in
For a shoe constructed with L=b, the wearer's body weight while walking at a more stressful pace or during recreational jogging tends to be or should be shifted more forward on the foot such that the landing surface ends in front of the apex 47 of the Calcaneus 50 with a greater depth of recess D. As a result of the increased stress of these activities, more leg muscle contraction and energy expenditure is required and the shoe helps the wearer to maintain a proper posture or gait.
Similarly, where L=c, corresponding in
Following a pattern of increasing stress involved in an activity, for L=d, where the landing surface terminates below the Talus as shown in
As known in the art, sprinting shoes, particularly for competitive athletes, have little if any cushioning and have a contact surface 22 only at the front of the shoe which may include holes into which spikes can be inserted. This is shown in
In other embodiments, e.g., L=f or g, a skilled dancer or gymnast will perform or train with their body weight on the ball of their foot or even the tips of their toes.
A shoe according to this invention may be further customized for an individual based on various factors and the full range of values for the length L are contemplated between those illustrated in
As an example of how an athletic shoe according to the present invention might be properly tailored to a particular individual, assume the intended wearer is a middle-aged woman who wants to lose extra weight by engaging in walking. This individual has had a previous injury to her right knee which may be aggravated by heel strikes while walking. According to
As a second example, assume the intended wearer of the shoe is a relatively fit college runner who competes in middle-distance races. The professional fitting the shoe selects a length L=c for the landing surface 22 (
Altering the scenario above such that the middle-distance runner, though fit, has had a prior injury to her right knee, a 10 mm depth of recess D might be appropriate to provide some cushioning with protection from heel strikes or discomfort while still providing acceptable performance characteristics for the competitive runner. The possible variations of this invention are numerous, but the utility of the invention in many possible scenarios should now be apparent to one skilled in the art.
In summary, an athletic shoe 10 constructed in accordance with this invention includes a proximal sole portion of a multiple part sole with a landing surface composed of a pressure deformable material under at least part of the forefoot, with the exception of L=g (need clarification here). The extent and thickness of the landing surface constructed for a particular embodiment of the shoe is determined with reference to a grid matching possible intended uses for the shoe to a suggested range of values for the length L of the landing surface 22 from the toe of the shoe rearward and the depth of the recess between the back portion of the heelless shoe and the ground. The embodiments of the invention disclosed provide a guide to the selection of a shoe suited to the particular needs of an individual, which may enhance the performance of the wearer in a particular activity, help to prevent injuries known to occur with other types of footwear existing in the prior art and provide additional options for rehabilitation for individuals having certain types of injuries or limitations.
This invention has been disclosed in terms of certain embodiments. It will be apparent that many modifications can be made to the disclosed apparatus without departing from the invention. Therefore, it is the intent of the appended claims to cover all such variations and modifications as come within the true spirit and scope of this invention.
Claims
1. An athletic shoe having an upper including a toe portion, a midsection and a rear portion and a multiple part sole forming an interior volume for receiving an individual's foot, the foot including a plantar surface and an internal skeletal structure including a big toe defining a proximal end of the shoe and a medial arch, said multiple part sole comprising:
- A. an inner sole for engaging the plantar surface;
- B. a midsole having an inner surface attached to the exterior of said inner sole to be substantially coextensive with said inner sole, said midsole having an outer surface;
- C. an outer sole attached to the outer surface of said midsole intermediate the inner and outer soles, said outer sole having a first portion extending from the proximal end of the shoe to a position being selected according to the intended use of the shoe and the characteristics of the wearer, said outer sole having a second contiguous portion extending from the selected position to the rear portion of the shoe, said first portion providing a landing surface for the shoe and said second portion being relatively thin as compared to said first portion thereby to help prevent injuries to the wearer during a given activity and promote proper gait during movement.
2. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the apex of the Calcaneum bone about 90% of the length of the shoe rearward from the toe of the shoe.
3. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the Calcaneum bone about 86-87% of the length of the shoe rearward from the toe of the shoe.
4. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the Calcaneum bone about 85% of the length of the shoe rearward from the toe of the shoe.
5. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the Talus bone that is about 62.5% of the length of the shoe rearward from the toe of the shoe.
6. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the joint between the Metatarsal and Cuneiform bones of the medial arch about 50% of the length of the shoe rearward from the toe of the shoe.
7. A shoe according to claim 1 in which said first portion of said outer sole extends from the proximal end of the shoe to a position beneath the joint between the Phalange and Metatarsal bones of the big toe about 25% of the length of the shoe rearward from the toe of the shoe.
8. A shoe according to claim 1 in which said first portion of said outer sole is limited to the toe of said shoe.
Type: Application
Filed: Mar 23, 2016
Publication Date: Sep 28, 2017
Inventor: Etienne Penka (Leominster, MA)
Application Number: 15/078,005