Welcome to the Podiatry Arena forums

You are currently viewing our podiatry forum as a guest which gives you limited access to view all podiatry discussions and access our other features. By joining our free global community of Podiatrists and other interested foot health care professionals you will have access to post podiatry topics (answer and ask questions), communicate privately with other members, upload content, view attachments, receive a weekly email update of new discussions, access other special features. Registered users do not get displayed the advertisements in posted messages. Registration is fast, simple and absolutely free so please, join our global Podiatry community today!

  1. Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
    Dismiss Notice
Dismiss Notice
Have you considered the Clinical Biomechanics Boot Camp Online, for taking it to the next level? See here for more.
Dismiss Notice
Have you liked us on Facebook to get our updates? Please do. Click here for our Facebook page.
Dismiss Notice
Do you get the weekly newsletter that Podiatry Arena sends out to update everybody? If not, click here to organise this.

Vimazi running shoes for running at different paces.

Discussion in 'Biomechanics, Sports and Foot orthoses' started by NewsBot, May 12, 2021.

  1. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1

    Attached Files:

  2. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
  3. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
  4. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
  5. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    Here is the patent granted for this shoe:
    https://patents.justia.com/patent/20200315291

    By tuning the rebound properties of the compressible layer to a runner's speed and optionally to specific regions of the compressible layer, cushioning can be maximized and energy losses minimized. Cushioning is maximized when the compressible layer compresses to near its elastic limit under the forces of running. Energy losses are minimized when the vertical (downward) component of the wearer's kinetic energy is converted into potential energy in the compressible layer during compression, and at least some of that stored potential energy is subsequently returned to the wearer by generating vertical (upward) kinetic energy. The amount of stored potential energy is determined by the amount of compression and the maximum force applied. Energy storage is maximized when the compressible layer is compressed to near its elastic limit.
    It will be appreciated that a faster running velocity necessitates a shorter ground contact time and higher associated ground reaction forces to generate the higher vertical acceleration of the body center of mass necessary to lift the body back up for the flight period between successive ground contact intervals (steps). A slower running velocity has longer contact times, requires a slower vertical acceleration of the center of mass, and is associated with lower peak ground reaction forces. The faster running speed will require that the compressible layer be tuned to the greater peak forces in order to store and return maximum energy to the runner's foot, while a slower running speed will require that the compressible layer be tuned to lesser forces. It will also be appreciated that any vertical kinetic energy not converted into stored potential energy will be lost and means that storing less spring potential energy will result in more energy loss.
    It will further be appreciated that the mass of the runner will influence the forces necessary to achieve the vertical acceleration associated with a specific running speed. A higher mass will require a higher force to achieve the vertical acceleration. Within the normal range of human body mass for runners, the differences in ground reaction forces are primarily influenced by the required vertical acceleration, because kinetic energy changes with the square of the vertical velocity and is linearly proportional to the mass. Consequently, a given pair of running shoes embodying the presently disclosed technology will be tuned to a specific range of running speeds and a given range of body masses. Runners will choose their running shoes accordingly.
    Different anatomical portions of the foot contact the ground at different times in the contact phase of the gait cycle, and also with different force magnitudes. Consequently, it may be beneficial to tune the portions of the midsole underlying distinct anatomical portions of the foot differently to take this into account. For example, the peak force in the heel is significantly lower than the peak force in the ball of foot region, requiring a lower spring constant in the heel than in the ball of foot in order to achieve similar amounts of compression. Similarly, the arch and toes regions experience lower peak forces relative to the ball and heel and require relatively lower spring constants.
    It will also be appreciated that the amount of potential energy stored in the compressible layer increases with increasing compression of the compressible layer roughly according to Equation 6. Furthermore, the maximum potential energy is limited by the limit of elasticity, which is defined as the maximum compression, xs-max.
    By means of the presently disclosed technology, a runner may recover a significant portion of the energy expended by the runner which would otherwise have been lost. Instead, the recovered energy will be used to provide a lift to the body as it accelerates upward. This returned energy will be small in each step but cumulatively will be a significant aid when running long distances.
    An article of footwear is disclosed here as having an upper and a sole structure secured to the upper. The sole structure consists of one or more midsole components with an inherent spring constant such that the ratio of the midsole potential energy (PE) to the maximum midsole potential energy (PEmax), approaches a value of 1.0. The range in ratio represents a practical range of variance a runner's ability to control running speed, variation in body mass of +/−10 kg, manufacturing tolerances for typical midsole materials. The PE/PEmax ratio is computed using the vertical propulsion peak force magnitude, Fimpulse, associated with different running speeds and a given set of physical parameters that includes the midsole dimensions and a runner mass range. It is possible to determine the spring constant mathematically for each region of the midsole that will yield the greatest cushioning and potential energy available for energy return (the maximum potential energy) by measuring or calculating Fimpulse for different running speeds from each adjacent point on the wearer's foot. In a preferred embodiment, the PE/PEmax ratio is between 0.95 and 1.05. In an alternative embodiment, the PE/PEmax ratio is between 0.85 and 1.15. In another alternative embodiment, the PE/PEmax ratio is between 0.80 and 1.20.
    A midsole component can be tuned to a specific set of boundary conditions at a point on the midsole, an area of the midsole, or at multiple different areas of the midsole. By treating the midsole as having four regions in the transverse plane that correspond to the heel, arch, ball-of-foot, and toes of the wearer's foot, the midsole can be constructed with separately tuned regions
    In one embodiment of the presently disclosed technology, the midsole is constructed with four regions corresponding anatomically to the wearer's heel, arch, ball-of-foot, and toes, each region being comprised entirely of, or encompassing within it, a tuned midsole structure. Furthermore, the preferred embodiment will have midsole structures that are tuned according to the wearer running speed and wearer mass.
    In an alternate embodiment of the presently disclosed technology, the four anatomical midsole regions can be further divided into subregions. The subregions may be of any shape or size that fit within the anatomically defined region. In one embodiment, the subregions are squares with dimensions of 4 mm×4 mm. Each subregion can be tuned to the specific forces acting on it by the corresponding anatomical subregion of the wearer's foot.
    By rearranging the terms algebraically, the PE/PEmax ratio can be expressed as a ratio of the actual spring constant, k, to an ideal spring constant, kideal. The k/kideal ratio can practically be applied to the manufacture of midsole components.
    Midsole structures are comprised of one or more materials and assembled in such a way as to exhibit spring-like properties according to Hooke's Law when acted on by a compressive force. The effect may be achieved in a multitude of ways using materials and constructions common in the industry and with physical dimensions and masses suitable for performance athletic footwear. A practical engineering approach to determine the midsole component physical properties is to apply the relevant Fimpulse for the runner mass and speed, the elastic limit for the compressible component, and Hooke's Law, to calculate the spring constant, kideal, that equates to the maximum spring displacement xs-max. Physical properties for an elastic solid can by derived from the spring constant and the conversion for Young's modulus.
    Y = k ideal  L S [ 5 ]
    where Y is the Young's modulus, L is the depth of the material, and S is the surface area of the material.
    Springs and elastic solids exhibit varying degrees of energy loss (damping) during a rebound cycle. The amount of energy loss will constrain the efficiency with which the spring element can convert its stored potential energy into kinetic energy. However, a high damping coefficient, and therefore a high energy loss, does not change the applicability of Hooke's Law to spring displacements below the proportionality limit. It is understood that the higher the percentage of decompression in the compressible layer, the greater the amount of the stored potential energy that is returned to the wearer.
    In one embodiment of the presently disclosed technology, any compressible component(s) incorporated into the shoe design will decompress (reexpand) to a high percentage of the original uncompressed dimension, reexpanding 90%. In an alternate embodiment, any of the compressible component swill decompress to a lesser percentage of 50%. In a further alternate embodiment, any of the compressible components we decompress to low percentage of 25%. In all embodiments, the compressible components within a single shoe may decompress by different percentages from each other.
    A running shoe consisting of (a) an upper that secures the foot to the shoe, and (b) a compressible sole structure under the upper that compresses in proportion to the amount of pressure applied during the gait cycle of the runner to no more than the limit of elasticity and decompresses when pressure is decreased and removed from the compressible sole structure during the ground contact phase of the gait cycle of the runner, can be constructed so that it is tuned to a runner's running speed as follows.
    This is done by taking into account the runner's gait cycle. The gait cycle of the runner to which the shoe is tuned consists of: first, a time when the shoe initially contacts the ground; second, a time during which gravity and the runner's leg muscles apply increasing force to the shoe; third, a time of maximum application of force to the shoe, fourth, a time of application of decreasing force to the shoe until the force applied to the shoe is zero but the shoe remains in contact with the ground; fifth, a time when the shoe is removed from contact with the ground; sixth, a time when the shoe is moved forward before again contacting the ground.
    The compressible sole layer is constructed so that it compresses to no more than its limit of elasticity upon application of increasing force to the shoe during the initial stage of the stride, and decompresses in response to decreasing force during the time after the maximum application of force to the shoe and until the shoe leaves the ground. The compressible sole layer most preferably decompresses substantially completely during the time after the maximum application of force to the shoe during the contact period of the runner and before the shoe leaves the ground during the gait cycle of the runner, but may decompress only 90% or even only 50%. In one embodiment, the compressible sole layer consists of a plurality of regions, each region of the compressible sole layer below a corresponding region of the foot (e.g. the heel, ball, and toe regions) and tuned to the forces applied to that region of the compressible sole layer by the corresponding region of the foot. The shoe can be tuned so that the cushioning and energy return are maximized for a running speed zone by tuning the ratio of k/kideal to approach a value of 1.0. A shoe according to this technology is tuned to match a runner's speed, preferably +/−0.3 m/s, but may also be tuned to match the runner's speed +/−1 m/s, or even +/−2 m/s.
    The advantages and features of novelty characterizing aspects of the presently disclosed technology are pointed out with particularity in the appended claims. To gain an improved understanding of the advantages and features of novelty, however, reference may be made to the following descriptive matter and accompanying figures that describe and illustrate various configurations and concepts related to the presently disclosed technology.
     
  6. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
  7. NewsBot

    NewsBot The Admin that posts the news.

    Articles:
    1
    This is one of the studies that the shoes are based on:

    Foot strike may not affect longitudinal arch compression
    Scott Tucker,Natalie Harold,Sarah R. Chang &David Boone
    Footwear Science Pages S16-S18 13 Jul 2021
    Link to study
     
Loading...

Share This Page