Abstract:
A variable weight athletic shoe is described is removably fitted with training weights of varying heaviness or the weights may be left off entirely without damaging the aesthetic appeal or functional aspects of the shoe. The weights are of various sizes and are quickly and securely coupled to the rear portion of the heel-enclosing section of the shoe with several types of attachment clips and latches. The weights also include magnetic inserts provided for health-enhancing reasons. In other variants of the invention, shoe weights are removably attached within cavities in the heel or arch sections of the shoe sole. Weights may also be attached across the instep of the athletic shoe. The shoe weights may be covered in various protective and decorative coverings and may contain lightening holes to achieve the desired weight in a given size.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention pertains to field of athletic shoes. More particularly, the invention relates to athletic shoes designed to accept a variable amount of additional weight for purposes of training and exercise. The weights for these athletic shoes further include magnetic inserts for health enhancing reasons. 
       BACKGROUND OF THE INVENTION 
       [0002]    Various shoe designs have been developed which include weights for purposes of providing additional exercise or weight training to the wearer of the shoe. U.S. Pat. No. 5,231,776 issued to Wagner incorporates a plurality of small metallic spheres entrapped in a lattice grid matrix molded to the sole. U.S. Pat. Nos. 5,638,613 and 4,709,921 issued to Williams and Valuikas et al., respectively, utilize flattened weights integrated into the soles of shoes, as does U.S. Pat. No. 3,109,245, issued to R. P. Glynn. More advanced shoes have included various means to add varying amounts of weight to the shoe. U.S. Pat. No. 4,777,743 issued to Roehrig, Jr. uses one or more weighted fastening straps disposed about the upper ankle portion of the shoe top. U.S. Pat. No. 4,686,781, issued to Bury includes a chamber in the sole of the shoe designed to accommodate lead shot or similar weighting material. U.S. Pat. Nos. 3,114,982 and 4,458,432, issued to McGowan, and Stempski, respectively, incorporate pockets to hold shoe weights. U.S. Pat. No. 7,028,417 issued to Tingle is directed to a therapeutic slipper having pockets designed to receive therapeutic devices such as magnets, satchels of herbal compositions, cold packs or hot packs. An instep panel with a pocket designed to receive therapeutic devices can be removably attached to the slipper. U.S. Pat. No. 6,360,457 issued to Qui et al. is directed to a health care shoe that has a plurality of magnets that are located above and below the user&#39;s foot. Either the sole or the insole has a plurality of cavities adapted to receive magnets that may be cemented in place. U.S. Pat. Application No. 2002/0193498 published for Brown is directed to shock reduction footwear that has a plurality of springs installed in the sole. A set of springs is supplemented by opposing magnets that may be a single rectangular plate-type magnet but preferably is a plurality of spaced parallel magnetic strips orientated across the width of the heel. 
         [0003]    Prior art designs for weighted shoes either do not provide a capability to remove or vary the weight attached to the shoe or provide only a limited capacity to vary the weight. Some of the designs include external weight pockets that provide relatively unbalanced weighting and do not integrate smoothly with the appearance of the shoe. Some of the designs allow the shoe weights to shift within cavities in the shoe, increasing the shoe&#39;s instability to the wearer. 
         [0004]    It is an objective of the present invention to provide for variable weighting of the shoe. It is a further objective to allow the wearer to remove the weight from the shoe entirely without interfering with the structural integrity of the shoe. It is a still further objective of the invention to have the weighting capability integrate smoothly with the appearance of the shoe. It is yet a further objective to permit the wearer to change the weighting of the shoe without the use of external tools. Finally, it is an objective of the invention, to provide removable weights for an athletic shoe that integrate magnetic inserts. 
         [0005]    While some of the objectives of the present invention are disclosed in the prior art, none of the inventions found include all of the requirements identified. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention addresses all of the deficiencies of prior art weighted shoe inventions and satisfies all of the objectives described above. A variable weight athletic shoe may be constructed from the following components. An athletic shoe having an upper portion and a resilient sole portion is provided. The upper portion has a forefoot enclosing section and a heel-enclosing section. The heel-enclosing section has a first side and a second side. The sole portion has a forward end, an after end and a bottom surface. The after end extends upwardly from the bottom surface to a top edge and upon the heel-enclosing section of the upper portion. 
         [0007]    A removable shoe weight is provided The weight is formed of a resilient material and is shaped to conform to the after end on the sole portion. The weight has an inner surface, an outer surface, a top edge and a bottom edge. The shoe weight including at least one magnetic insert. Means are provided for removably attaching the weight to the after end of the sole portion. 
         [0008]    In a variation of the invention, the means for removably attaching the weight to the after end of the sole portion further comprises a cavity located between the bottom surface and the top edge of the after end of the sole portion of the athletic shoe. The cavity has an upper edge, a lower edge and a back portion and is sized, shaped and disposed to receive the removable shoe weight. 
         [0009]    A lower receiving notch located at the lower edge of the cavity and an upper receiving notch located at the upper edge of the cavity are provided. A projecting tab is fixedly attached to the bottom edge of the weight. The tab is sized, shaped and located to removably engage the lower receiving notch of the cavity. 
         [0010]    A resilient latch is fixedly attached to the top edge of the weight. The latch is sized, shaped and located to releasably engage the upper receiving notch of the cavity. In use, the projecting tab is inserted into the lower receiving notch and the weight is tilted upwardly toward the athletic shoe. The resilient latch is pressed downwardly toward the projecting tab, and the weight is pressed into the cavity. The resilient latch is released to engage the upper receiving notch. Thus the weight is removably attached to the athletic shoe. 
         [0011]    In another variation of the invention, a plurality of weights of varying heaviness, formed to attach to the cavity of the athletic shoe, are provided. Each of the shoe weights including at least one magnetic insert. In still another variation, the weights are encased in a covering material selected to protect the weight from corrosive forces and enhance the appearance of the shoe. 
         [0012]    In yet another variation of the invention, the means for removably attaching the weight to the after end of the sole portion further comprises a cavity located between the bottom surface and the top edge of the after end of the sole portion of the athletic shoe. The cavity has an upper edge, a lower edge and a back portion and is sized, shaped and disposed to receive the removable shoe weight. 
         [0013]    An upper receiving notch is located at the upper edge of the cavity and a latch is located adjacent to the lower edge of the cavity. The latch comprises a resilient, elongated member located roughly parallel to the back portion of the cavity and a projecting finger extending at a right angle from the elongated member adjacent to the cavity. 
         [0014]    A projecting lip is formed at the top edge of the weight. The lip is sized, shaped and located to engage the upper receiving notch. A receiving tab is fixedly attached to the bottom edge of the weight. The tab includes an orifice sized, shaped and located to removably engage the projecting finger of the latch. 
         [0015]    In use, the projecting lip is inserted into the upper receiving notch, and the weight is tilted downwardly toward the athletic shoe. The elongated member of the latch is pulled outwardly from the athletic shoe and the weight is pressed into the cavity. The elongated member is released to allow the projecting finger to engage the orifice in the receiving tab. Thus, the weight is removably attached to the athletic shoe. 
         [0016]    In a further variation, an athletic shoe having an upper portion and a resilient sole portion is provided. The upper portion has a forefoot enclosing section and a heel-enclosing section. The heel-enclosing section has a first side and a second side. The sole portion has a predetermined thickness, a forward end, an after end and a bottom surface. 
         [0017]    The sole portion includes a heel weight cavity that has an opening at the after end of the sole portion and extends forwardly for a first predetermined distance. The cavity has an upper surface, a lower surface and a front surface. 
         [0018]    A weight is provided that has a forward end, a rearward end, a top surface and a bottom surface. The weight is shaped to fit slidably within the cavity. The weight includes at least one magnetic insert. Means are provided for ejecting the weight from the cavity as are means for releasably retaining the weight within the cavity. 
         [0019]    In this variation, a plurality of weights of varying heaviness, formed to fit slidably within the heel weight cavity of the athletic shoe, are also provided. Each of the weights includes at least one magnetic insert. 
         [0020]    In another variation of the invention the means for ejecting the weight from the heel weight cavity comprises a first compression spring secured to the front surface of the weight cavity and disposed between the cavity and the weight. 
         [0021]    In still another variation, the means for releasably retaining the weight within the heel weight cavity comprises a detent opening positioned in the upper surface of the weight cavity at a right angle to the upper surface and a latch fixedly attached to the top surface of the weight. The latch is positioned adjacent to the rearward end of the weight. The latch includes a resilient, elongated member projecting upwardly from the top surface of the weight at an acute angle and a projecting finger extending at a right angle from the member. The finger is sized, shaped and located to releasably engage the detent opening of the cavity. 
         [0022]    In use, the weight is inserted into the weight cavity, thereby compressing the first compression spring. The elongated member is pressed downwardly toward the upper surface of the weight. The elongated member is then released, thereby permitting the elongated member to spring upwardly and the projecting finger to engage the detent opening in the weight cavity. Thus removably retaining the weight within the weight cavity of the athletic shoe. To remove the weight from the cavity the elongated member is pressed downwardly against the weight, thereby disengaging the projecting finger of the latch from the detent opening. The first compression spring will then urge the weight outwardly from the cavity, allowing the wearer of the shoe to remove the weight. 
         [0023]    In yet a further variation of the invention, a variable weight athletic shoe may be constructed comprising an athletic shoe having an upper portion and a resilient sole portion. The upper portion has a forefoot enclosing section and a heel-enclosing section. The sole portion has a predetermined thickness, a forward end, an after end, a central arch section and a bottom surface. 
         [0024]    The arch section is located between the forward end and the after end of the sole portion and has a first side and a second side. The arch section includes an arch weight cavity that has an opening at the first side of the sole portion and extends toward the second side for a second predetermined distance. The cavity has an upper surface, a lower surface and a distal end surface. 
         [0025]    A weight, having a forward end, a rearward end, a top surface and a bottom surface is provided. The weight is shaped to fit slidably within the cavity. The weight includes at least one magnetic insert. Means are provided for ejecting the weight from the cavity and for releasably retaining the weight within the cavity. 
         [0026]    In this variation a plurality of weights of varying heaviness, formed to fit slidably within the arch cavity of the athletic shoe, are provided. Each of the weights includes at least one magnetic insert. 
         [0027]    In still another variation of the invention the means for ejecting the weight from the arch weight cavity comprises a second compression spring secured to the distal end surface of the weight cavity and disposed between the cavity and the weight. 
         [0028]    In yet a further variation, the means for releasably retaining the weight within the arch weight cavity comprises a detent opening positioned in the upper surface of the weight cavity at a right angle to the upper surface of the cavity and a latch fixedly attached to the top surface of the weight. The latch is attached adjacent to the rearward end of the weight. The latch includes a resilient, elongated member projecting upwardly from the top surface of the weight at an acute angle and a projecting finger extending at a right angle from the member. The finger is sized, shaped and located to releasably engage the detent opening of the cavity. 
         [0029]    In use, the weight is inserted into the weight cavity, thereby compressing the second compression spring. The elongated member is pressed downwardly toward the top surface of the weight, and the elongated member is then released. This permits the elongated member to spring upwardly and the projecting finger to engage the detent opening in the weight cavity thus removably retaining the weight within the weight cavity of the athletic shoe. 
         [0030]    When the elongated member is pressed downwardly against the weight, thereby disengaging the projecting finger of the latch from the detent opening, the second compression spring will urge the weight outwardly from the cavity, allowing the wearer of the shoe to remove the weight from the cavity. 
         [0031]    In still a further variation of the invention the means for removably attaching the weight to the after end of the sole portion further comprises first and second L-shaped alignment rails. The alignment rails are located on the after end of the sole portion adjacent its top edge. A cavity is provided. The cavity has an upper edge, a lower edge and a back wall and is centrally located between the first and second L-shaped alignment rails on the after end of the sole portion. The cavity is spaced from the bottom surface of the sole portion. 
         [0032]    A latching member is provided. The latching member includes a vertical portion that has first end and a second end. The first end is pivotally attached to the lower edge of the cavity. A projecting finger element is fixedly attached to the second end of the latching member and extends outwardly from the cavity. 
         [0033]    A third compression spring is located between the back wall of the cavity and the latching member and urges the latching member outwardly from the cavity. First and second access opening are provided. The access openings are sized, shaped and located on the inner surface of the removable shoe weight to receive the first and second L-shaped alignment rails. 
         [0034]    First and second L-shaped alignment slots are provided. The alignment slots extend from the first and second access openings to the top edge of the weight. The at least one magnetic insert is located between said first and second access openings. The alignment slots are sized, shaped and located to slidably receive the L-shaped alignment rails. 
         [0035]    A receiving notch is provided. The receiving notch is sized shaped and located adjacent to the bottom edge of the weight to removably engage the projecting finger element of the latching member. In use, the first and second access openings in the inner surface of the shoe weight are located over the first and second L-shaped alignment rails. The weight is urged downwardly so that the first and second alignment rails will engage the first and second alignment slots. The latching member is urged inwardly against the coil spring, thereby permitting the receiving notch to pass the projecting finger element of the latching member. When the latching member is released the projecting finger element engages the receiving notch in the weight, thereby removably attaching the weight to the athletic shoe. 
         [0036]    When the latching member is urged inwardly against the coil spring and the weight pulled upwardly from the athletic shoe the projecting finger element will disengage from the receiving notch. The weight will then slide upwardly permitting the first and second L-shaped alignment rails to enter the first and second access openings, thus permitting the weight to be pulled outwardly and removed from the after end of the sole portion of the athletic shoe. 
         [0037]    In still another variation a plurality of weights of varying heaviness, formed to attach to the after end of the sole portion of the athletic shoe, are provided. Each of the weights includes at least one magnetic insert. 
         [0038]    In a yet a further variation, the weights are encased in a covering material selected to protect the weight from corrosive forces and enhance the appearance of the shoe. 
         [0039]    In still another variation of the invention, the means for removably attaching the weight to the after end of the sole portion further comprises first and second L-shaped brackets located on the first and second sides of the heel-enclosing section. Each of the L-shaped brackets is spaced a third predetermined distance from the bottom surface of the sole portion. 
         [0040]    A weight is provided that includes a first weight portion, a second weight portion and a cam-lock lever. The cam-lock lever has a first end, a second end, a top surface and a bottom surface. The first weight portion has a first end and a second end and includes at least one magnetic insert. A first hooking element sized and shaped to removably engage the first L-shaped bracket is provided. The first hooking element is located at the first end of the first weight portion. 
         [0041]    A plurality of adjustment notches located adjacent the second end of the first weight portion are provided. The second weight portion has a first end and a second end. A second hooking element sized and shaped to removably engage the second L-shaped bracket is provided. The second hooking element is located at the second end of the second weight portion. 
         [0042]    A pivot pin is located adjacent the first end of the second weight portion. A relief depression sized and shaped to accept the bottom surface of the cam-lock lever and spaced from the first end of the second weight portion is provided. The cam-lock lever is pivotally attached at the first end to the pivot pin of the second weight portion. A notch engaging pall sized, shaped and located to engage the plurality of adjustment notches on the first weight portion is provided. The pall is pivotally mounted between the first end and the second end of the cam-lock lever. 
         [0043]    An opening is located between the first end of the cam-lock lever and the pivotal mounting of the notch-engaging pall. The opening is sized and shaped to permit the second end and plurality of adjustment notches of the first weight portion to pass slidably through it. An operating handle is located at the second end of the cam-lock lever. 
         [0044]    In operation the second end of the first weight portion is inserted through the opening in the cam-lock lever and the cam-lock lever is moved to a first, open position with the operating handle. The first hooking element is then located over the first L-shaped bracket and the second hooking element is located over the second L-shaped bracket. The pall then engages one of the adjusting notches on the first weight portion and the cam-lock lever is moved to a second, closed position. The bottom surface of the cam-lock lever is now located in the relief depression of the second weight portion and the first and second weight portions of the weight will be removably attached to the after end of the sole portion of the athletic shoe. 
         [0045]    When the operating handle is moved to locate the cam-lock lever to the first, open position the first and second hooking elements will disengage the first and second L-shaped brackets and the weight may be removed from the athletic shoe. 
         [0046]    Still another variation further comprises a plurality of weights of varying heaviness formed to attach to the after end of the sole portion of the athletic shoe. Each of the weights includes at least one magnetic insert. 
         [0047]    Yet a further variation of the invention comprises an athletic shoe having an upper portion and a resilient sole portion. The upper portion of the athletic shoe has a forefoot-enclosing section and a heel-enclosing section. The forefoot enclosing section has a first side and a second side and includes at least one pair of first and second L-shaped brackets disposed on the first and second sides. 
         [0048]    A weight is provided that includes a first weight portion, a second weight portion and a cam-lock lever. The cam-lock lever has a first end, a second end, a top surface and a bottom surface. The first weight portion has a first end and a second end. The first weight portion includes at least one magnetic insert. A first hooking element sized and shaped to removably engage the first L-shaped bracket is provided. The first hooking element is located at the first end of the first weight portion. 
         [0049]    A plurality of adjustment notches located adjacent the second end of the first weight portion are provided. The second weight portion has a first end and a second end. A second hooking element sized and shaped to removably engage the second L-shaped bracket is provided. The second hooking element is located at the second end of the second weight portion. 
         [0050]    A pivot pin is located adjacent the first end of the second weight portion. A relief depression sized and shaped to accept the bottom surface of the cam-lock lever and spaced from the first end of the second weight portion is provided. The cam-lock lever is pivotally attached at the first end to the pivot pin of the second weight portion. A notch engaging pall sized, shaped and located to engage the plurality of adjustment notches on the first weight portion is provided. The pall is pivotally mounted between the first end and the second end of the cam-lock lever. 
         [0051]    An opening is located between the first end of the cam-lock lever and the pivotal mounting of the notch-engaging pall. The opening is sized and shaped to permit the second end and plurality of adjustment notches of the first weight portion to pass slidably through it. An operating handle is located at the second end of the cam-lock lever. 
         [0052]    In operation the second end of the first weight portion is inserted through the opening in the cam-lock lever and the cam-lock lever is moved to a first, open position with the operating handle. The first hooking element is then located over the first L-shaped bracket and the second hooking element is located over the second L-shaped bracket. The pall then engages one of the adjusting notches on the first weight portion and the cam-lock lever is moved to a second, closed position. The bottom surface of the cam-lock lever is now located in the relief depression of the second weight portion and the first and second weight portions of the weight will be removably attached to the forefoot-enclosing section of the athletic shoe. 
         [0053]    When the operating lever is moved to locate the cam-lock lever to the first, open position the first and second hooking elements will disengage the first and second L-shaped brackets and the weight may be removed from the athletic shoe. 
         [0054]    Still another variation further comprises a plurality of weights of varying heaviness formed to attach to the forefoot-enclosing section of the athletic shoe. Each of the weights includes at least one magnetic insert. 
         [0055]    An appreciation of the other aims and objectives of the present invention and an understanding of it may be achieved by referring to the accompanying drawings and the detailed description of a preferred embodiment. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0056]      FIG. 1  is a front elevation of a first embodiment of a removable shoe weight with magnetic insert, employing a first latching mechanism, attached to the after end of the sole portion of an athletic shoe; 
           [0057]      FIG. 2  is a perspective view of the  FIG. 1  embodiment illustrating a first embodiment of a weight-retaining clip with magnetic insert; 
           [0058]      FIG. 3  is a side elevation of the  FIG. 1  embodiment attached to the athletic shoe; 
           [0059]      FIG. 4  is a cross-sectional side elevation of the  FIG. 1  embodiment taken along the line  4 - 4  and illustrating the magnetic insert; 
           [0060]      FIG. 5  is a perspective view of the  FIG. 1  embodiment with holes provided for lighter weight and illustrating the magnetic insert; 
           [0061]      FIG. 6  is a cross-sectional side elevation of a second embodiment of a removable shoe weight, employing a second latching mechanism, attached to the after end of the sole portion of an athletic shoe and illustrating the magnetic insert; 
           [0062]      FIG. 7  is a cross-sectional side elevation of the second embodiment of a removable shoe weight with magnetic insert inserted into a cavity in the heel portion of an athletic shoe; 
           [0063]      FIG. 8  is a rear elevational view of the  FIG. 7  embodiment of the removable shoe weight illustrating the receiving tab, orifice and magnetic insert; 
           [0064]      FIG. 9  is a partial break-away side elevational view of a third embodiment of a removable shoe weight with magnetic insert installed in the heel of an athletic shoe; 
           [0065]      FIG. 10  is a perspective view of the  FIG. 9  embodiment illustrating the latching mechanism; 
           [0066]      FIG. 11  is a perspective view of the  FIG. 9  embodiment with holes provided for lighter weight and illustrating the magnetic insert; 
           [0067]      FIG. 12  is a partial break-away side elevational view of a fourth embodiment of a removable shoe weight with magnetic insert, employing the first latching mechanism, attached to the arch of an athletic shoe; 
           [0068]      FIG. 13  is a cross-sectional side elevational view of the  FIG. 12  embodiment taken along the line  13 - 13  illustrating the magnetic insert in cross-sectional view. 
           [0069]      FIG. 14  is a cross-sectional side elevation of a fifth embodiment of a removable shoe weight, employing a third latching mechanism, attached to the after end of the sole portion of an athletic shoe and illustrating the magnetic insert; 
           [0070]      FIG. 15  is a perspective view of the  FIG. 14  embodiment illustrating the latching mechanism, alignment rails and inner surface features of the shoe weight and illustrating the magnetic insert; 
           [0071]      FIG. 16  is a rear elevational view of a sixth embodiment of a removable shoe weight with magnetic insert, illustrating a cam-lock latching mechanism attached to the after end of the sole portion of an athletic shoe; 
           [0072]      FIG. 17  is a plan view of the  FIG. 16  embodiment illustrating the cam-lock latching mechanism in a closed position; 
           [0073]      FIG. 18  is a plan view of the  FIG. 16  embodiment illustrating the cam-lock latching mechanism in an open position; and 
           [0074]      FIG. 19  is a perspective view of the  FIG. 16  shoe weight with magnetic insert attached to the forefoot enclosing section of the athletic shoe. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0075]    As illustrated in  FIGS. 1-19 , a variable weight athletic shoe  10  may be constructed from the following components. As illustrated in  FIGS. 1 and 3 , an athletic shoe  14  having an upper portion  18  and a resilient sole portion  22  is provided. The upper portion  18  has a forefoot enclosing section  26  and a heel-enclosing section  30 . The heel-enclosing section  30  has a first side  34  and a second side  38 . The sole portion  22  has a forward end  42 , an after end  46  and a bottom surface  50 . The after end  46  extends upwardly from the bottom surface  50  to a top edge  54  and upon the heel-enclosing section  30  of the upper portion  18 . 
         [0076]    As illustrated in  FIGS. 1-5 , a removable shoe weight  58  is provided. The weight is formed of a resilient material and is shaped to conform to the after end  46  on the sole portion  22 . The weight  58  has an inner surface  62 , an outer surface  66 , a top edge  70  and a bottom edge  74 . The shoe weight includes at least one magnetic insert  76 . Means  78  are provided for removably attaching the weight  58  to the after end  46  of the sole portion  22 . 
         [0077]    In a variation of the invention, as illustrated in  FIG. 4 , the means.  78  for removably attaching the weight  58  to the after end  46  of the sole portion  22  further comprises a cavity  82  located between the bottom surface  50  and the top edge  54  of the after end  46  of the sole portion  22  of the athletic shoe  14 . The cavity  82  has an upper edge  86 , a lower edge  90  and a back portion  94  and is sized, shaped and disposed to receive the removable shoe weight  58 . 
         [0078]    A lower receiving notch  98  located at the lower edge  90  of the cavity  82  and an upper receiving notch  102  located at the upper edge  86  of the cavity  82  are provided. A projecting tab  106  is fixedly attached to the bottom edge  74  of the weight  58 . The tab  106  is sized, shaped and located to removably engage the lower receiving notch  98  of the cavity  82 . 
         [0079]    As shown in  FIGS. 2 ,  4  and  5 , a resilient latch  110  is fixedly attached to the top edge  70  of the weight  58 . The latch  110  is sized, shaped and located to releasably engage the upper receiving notch  102  of the cavity  82 . In use, the projecting tab  106  is inserted into the lower receiving notch  98  and the weight  58  is tilted upwardly toward the athletic shoe  14 . The resilient latch  110  is pressed downwardly toward the projecting tab  106 , and the weight  58  is pressed into the cavity  82 . The resilient latch  110  is released to engage the upper receiving notch  102 . Thus the weight  58  is removably attached to the athletic shoe  14 . 
         [0080]    In another variation of the invention, illustrated in  FIG. 5 , a plurality of weights  58  of varying heaviness, formed to attach to the cavity  82  of the athletic shoe  14 , are provided. Each of the shoe weights includes at least one magnetic insert  76 . In still another variation, the weights  58  are encased in a covering material selected to protect the weight from corrosive forces and enhance the appearance of the shoe  14 . 
         [0081]    In yet another variation of the invention, illustrated in  FIGS. 6-8 , the means  78  for removably attaching the weight  58  to the after end  46  of the sole portion  22  further comprises a cavity  114  located between the bottom surface  50  and the top edge  54  of the after end  46  of the sole portion  22  of the athletic shoe  14 . The cavity  114  has an upper edge  118 , a lower edge  122  and a back portion  126  and is sized, shaped and disposed to receive the removable shoe weight  58 . 
         [0082]    An upper receiving notch  130  is located at the upper edge  118  of the cavity  114  and a latch  134  is located adjacent to the lower edge  122  of the cavity  114 . The latch  134  comprises a resilient, elongated member  138  located roughly parallel to the back portion  126  of the cavity  114  and a projecting finger  142  extending at a right angle from the elongated member  138  adjacent to the cavity  114 . 
         [0083]    A projecting lip  146  is formed at the top edge  70  of the weight  58 . The lip  146  is sized, shaped and located to engage the upper receiving notch  130 . A receiving tab  150  is fixedly attached to the bottom edge  74  of the weight  58 . The tab  150  includes an orifice  154  sized, shaped and located to removably engage the projecting finger  142  of the latch  134 . 
         [0084]    In use, the projecting lip  146  is inserted into the upper receiving notch  130 , and the weight  58  is tilted downwardly toward the athletic shoe  14 . The elongated member  138  of the latch  134  is pulled outwardly from the athletic shoe  14  and the weight  58  is pressed into the cavity  114 . The elongated member  138  is released to allow the projecting finger  142  to engage the orifice  154  in the receiving tab  150 . Thus, the weight  58  is removably attached to the athletic shoe  14 . 
         [0085]    In a further variation, as illustrated in FIGS.  3  and  9 - 11  an athletic shoe  14  having an upper portion  18  and a resilient sole portion  22  is provided. The upper portion  18  has a forefoot enclosing section  26  and a heel-enclosing section  30 . The heel-enclosing section  30  has a first side  34  and a second side  38 . The sole portion  22  has a predetermined thickness  158 , and a forward end  42 , an after end  46  and a bottom surface  50 . 
         [0086]    The sole portion  22  includes a heel weight cavity  162  that has an opening  166  at the after end  46  of the sole portion  22  and extends forwardly for a first predetermined distance  170 . The cavity  162  has an upper surface  174 , a lower surface  178  and a front surface  182 . 
         [0087]    A weight  186  is provided that has a forward end  190 , a rearward end  194 , a top surface  198  and a bottom surface  202 . The weight  186  is shaped to fit slidably within the cavity  162 . The weight includes at least one magnetic insert  76 . Means  206  are provided for ejecting the weight  186  from the cavity  162  as are means  210  for releasably retaining the weight  186  within the cavity  162 . 
         [0088]    In this variation, as illustrated in  FIG. 11 , a plurality of weights  186  of varying heaviness, formed to fit slidably within the heel weight cavity  162  of the athletic shoe  14 , are also provided. Each of the weights includes at least one magnetic insert  76 . 
         [0089]    In another variation of the invention, as illustrated in  FIGS. 9-11 , the means  206  for ejecting the weight  186  from the heel weight cavity  162  comprises a first compression spring  214  secured to the front surface  182  of the weight cavity  162  and disposed between the cavity  162  and the weight  186 . 
         [0090]    In still another variation, as illustrated in  FIGS. 9-11 , the means  210  for releasably retaining the weight  186  within the heel weight cavity  162  comprises a detent opening (not shown) positioned in the upper surface  174  of the weight cavity  162  at a right angle to the upper surface  174  and a latch  218  fixedly attached to the top surface  198  of the weight  186 . The latch  218  is positioned adjacent to the rearward end  194  of the weight  186 . The latch  218  includes a resilient, elongated member  222  projecting upwardly from the top surface  198  of the weight  186  at an acute angle and a projecting finger  226  extending at a right angle from the elongated member  222 . The finger  226  is sized, shaped and located to releasably engage the detent opening of the cavity  162 . 
         [0091]    In use, the weight  186  is inserted into the weight cavity  162 , thereby compressing the first compression spring  214 . The elongated member  222  is pressed downwardly toward the upper surface  198  of the weight  186 . The elongated member  222  is then released, thereby permitting the elongated member  222  to spring upwardly and the projecting finger  226  to engage the detent opening in the weight cavity  162 . Thus removably retaining the weight  186  within the weight cavity  162  of the athletic shoe  14 . To remove the weight  186  from the cavity  162  the elongated member  222  is pressed downwardly against the weight  186 , thereby disengaging the projecting finger  226  of the latch  218  from the detent opening. The first compression spring  214  will then urge the weight  186  outwardly from the cavity  162 , allowing the wearer of the shoe  14  to remove the weight  186 . 
         [0092]    In yet a further variation of the invention, illustrated in  FIGS. 12 and 13 , a variable weight athletic shoe  10  may be constructed comprising an athletic shoe  14  having an upper portion  18  and a resilient sole portion  22 . The upper portion  18  has a forefoot enclosing section  26  and a heel-enclosing section  30 . The sole portion  22  has a predetermined thickness  158 , and a forward end  42 , an after end  46 , a central arch section  230  and a bottom surface  50 . 
         [0093]    The arch section  230  is located between the forward end  42  and the after end  46  of the sole portion  22  and has a first side  234  and a second side (not shown). The arch section  230  includes an arch weight cavity  242  that has an opening  246  at the first side  234  of the sole portion  22  and extends toward the second side for a second predetermined distance  250 . The cavity  242  has an upper surface  254 , a lower surface  258  and a distal end surface  262 . 
         [0094]    A weight  266 , having a forward end  270 , a rearward end  274 , a top surface  278  and a bottom surface  282  is provided. The weight  266  is shaped to fit slidably within the cavity  242 . The weight includes at least one magnetic insert  76 . Means  286  for ejecting the weight  266  from the cavity  242  and means  290  for releasably retaining the weight  266  within the cavity  242  are provided. 
         [0095]    In this variation a plurality of weights  266  of varying heaviness, formed to fit slidably within the arch cavity  242  of the athletic shoe  14 , are provided. Each of the weights includes at least one magnetic insert  76 . 
         [0096]    In still another variation of the invention the means  286  for ejecting the weight  266  from the arch weight cavity  242  comprises a second compression spring  294  secured to the distal end surface  262  of the weight cavity  242  and disposed between the cavity  242  and the weight  266 . 
         [0097]    In yet a further variation, the means  290  for releasably retaining the weight  266  within the arch weight cavity  242  comprises a detent opening  298  positioned in the upper surface  254  of the weight cavity  242  at a right angle to the upper surface  254  of the cavity  242  and a latch  302  fixedly attached to the top surface  278  of the weight  266 . The latch  302  is attached adjacent to the rearward end  274  of the weight  266 . The latch  302  includes a resilient, elongated member  306  projecting upwardly from the top surface  278  of the weight  266  at an acute angle and a projecting finger  310  extending at a right angle from the elongated member  306 . The finger  310  is sized, shaped and located to releasably engage the detent opening  298  of the cavity  242 . 
         [0098]    In use, the weight  266  is inserted into the weight cavity  242 , thereby compressing the second compression spring  294 . The elongated member  306  is pressed downwardly toward the top surface  278  of the weight  266 , and the elongated member  306  is then released. This permits the elongated member  306  to spring upwardly and the projecting finger  310  to engage the detent opening  298  in the weight cavity  242  thus removably retaining the weight  266  within the weight cavity  242  of the athletic shoe  14 . 
         [0099]    When the elongated member  306  is pressed downwardly against the weight  266 , thereby disengaging the projecting finger  310  of the latch  302  from the detent opening  298 , the second compression spring  294  will urge the weight  266  outwardly from the cavity  242 , allowing the wearer of the shoe  14  to remove the weight  266  from the cavity  242 . 
         [0100]    In still a further variation of the invention, illustrated in  FIGS. 14 and 15 , the means  314  for removably attaching the weight  378  to the after end  46  of the sole portion  22  further comprises first  322  and second  326  L-shaped alignment rails. The alignment rails  322 ,  326  are located on the after end  46  of the sole portion  22  adjacent its top edge  54 . A cavity  330  is provided. The cavity  330  has an upper edge  334 , a lower edge  338  and a back wall  342  and is centrally located between the first  322  and second  326  L-shaped alignment rails on the after end  46  of the sole portion  22 . The cavity  330  is spaced from the bottom surface  50  of the sole portion  22 . 
         [0101]    A latching member  346  is provided. The latching member  346  includes a vertical portion  350  that has first end  354  and a second end  358 . The first end  354  is pivotally attached to the lower edge  338  of the cavity  330 . A projecting finger element  362  is fixedly attached to the second end  358  of the latching member  346  and extends outwardly from the cavity  330 . A third compression spring  368  is located between the back wall  342  of the cavity  330  and the latching member  346  and urges the latching member  346  outwardly from the cavity  330 . 
         [0102]    First  366  and second  370  access opening are provided. The access  366 ,  370  openings are sized, shaped and located on the inner surface  374  of the removable shoe weight  378  to receive the first  322  and second  326  L-shaped alignment rails. 
         [0103]    First  382  and second  386  L-shaped alignment slots are provided. The alignment slots  382 ,  386  extend from the first  366  and second  370  access openings to the top edge  390  of the weight  378 . The at least one magnetic insert  76  is located between said first and second access openings. The alignment slots  382 ,  386  are sized, shaped and located to slidably receive the L-shaped alignment rails  322 ,  326 . 
         [0104]    A receiving notch  394  is provided. The receiving notch  394  is sized shaped and located adjacent to the bottom edge  398  of the weight  378  to removably engage the projecting finger element  362  of the latching member  346 . In use, the first  366  and second  370  access openings in the inner surface  374  of the shoe weight  378  are located over the first  322  and second  326  L-shaped alignment rails. The weight  378  is urged downwardly so that the first  322  and second  326  alignment rails will engage the first  382  and second  386  alignment slots. The latching member  346  is urged inwardly against the coil spring  366 , thereby permitting the receiving notch  394  to pass the projecting finger element  362  of the latching member  346 . When the latching member  346  is released the projecting finger element  362  engages the receiving notch  394  in the weight  378 , thereby removably attaching the weight  378  to the athletic shoe  14 . 
         [0105]    When the latching member  346  is urged inwardly against the coil spring  366  and the weight  378  pulled upwardly from the athletic shoe  14  the projecting finger element  362  will disengage from the receiving notch  394 . The weight  378  will then slide upwardly permitting the first  322  and second  326  L-shaped alignment rails to enter the first  366  and second  370  access openings, thus permitting the weight  378  to be pulled outwardly and removed from the after end  46  of the sole portion  22  of the athletic shoe  14 . 
         [0106]    In still another variation a plurality of weights  378  of varying heaviness, formed to attach to the after end  46  of the sole portion  22  of the athletic shoe  14 , are provided. Each of the weights includes at least one magnetic insert  76 . 
         [0107]    In a yet a further variation, the weights  378  are encased in a covering material selected to protect the weight  378  from corrosive forces and enhance the appearance of the shoe  14 . 
         [0108]    In still another variation of the invention, illustrated in  FIGS. 16-18  the means  398  for removably attaching the weight  402  to the after end  46  of the sole portion  22  further comprises first  406  and second  410  L-shaped brackets located on the first  34  and second  38  sides of the heel-enclosing section  30 . Each of the L-shaped brackets  406 ,  410  is spaced a third predetermined distance  414  from the bottom surface  50  of the sole portion  22 . 
         [0109]    The weight  402  includes a first weight portion  422 , a second weight portion  426  and a cam-lock lever  430 . The cam-lock lever  430  has a first end  434 , a second end  438 , a top surface  442  and a bottom surface  446 . The first weight portion  422  has a first end  450  and a second end  454  and includes at least one magnetic insert  76 . A first hooking element  458  sized and shaped to removably engage the first  406  L-shaped bracket is provided. The first hooking element  458  is located at the first end  450  of the first weight portion  422 . 
         [0110]    A plurality of adjustment notches  462  located adjacent the second end  454  of the first weight portion  422  are provided. The second weight portion  426  has a first end  466  and a second end  470 . A second hooking element  474  sized and shaped to removably engage the second L-shaped bracket  410  is provided. The second hooking element  474  is located at the second end  470  of the second weight portion  426 . 
         [0111]    A pivot pin  478  is located adjacent the first end  466  of the second weight portion  426 . A relief depression  482  sized and shaped to accept the bottom surface  446  of the cam-lock lever  430  and spaced from the first end  446  of the second weight portion  426  is provided. The cam-lock lever  430  is pivotally attached at the first end  434  to the pivot pin  478  of the second weight portion  426 . A notch-engaging pall  482  sized, shaped and located to engage the plurality of adjustment notches  462  on the first weight portion  422  is provided. The pall  482  is pivotally mounted between the first end  434  and the second end  438  of the cam-lock lever  430 . 
         [0112]    An opening  486  is located between the first end  434  of the cam-lock lever  430  and the pivotal mounting  490  of the notch-engaging pall  482 . The opening  486  is sized and shaped to permit the second end  454  and plurality of adjustment notches  462  of the first weight portion  422  to pass slidably through it. An operating handle  494  is located at the second end  438  of the cam-lock lever  430 . 
         [0113]    In operation the second end  454  of the first weight portion  422  is inserted through the opening  486  in the cam-lock lever  430  and the cam-lock lever  430  is moved to a first, open position ( FIG. 18 ) with the operating handle  494 . The first hooking element  458  is then located over the first L-shaped bracket  406  and the second hooking element  474  is located over the second L-shaped bracket  410 . The pall  482  then engages one of the adjusting notches  462  on the first weight portion  422  and the cam-lock lever  430  is moved to a second, closed position ( FIGS. 16 and 17 ). The bottom surface  446  of the cam-lock lever  430  is now located in the relief depression  482  of the second weight portion  426  and the first  422  and second  426  weight portions of the weight  402  will be removably attached to the after end  46  of the sole portion  22  of the athletic shoe  14 . 
         [0114]    When the operating handle  494  is moved to locate the cam-lock lever  430  to the first, open position the first  458  and second  474  hooking elements will disengage the first  406  and second  410  L-shaped brackets and the weight  402  may be removed from the athletic shoe  14 . 
         [0115]    Still another variation further comprises a plurality of weights  402  of varying heaviness formed to attach to the after end  46  of the sole portion of the athletic shoe. Each of the weights includes at least one magnetic insert  76 . 
         [0116]    Yet a further variation of the invention, illustrated in  FIG. 19 , comprises an athletic shoe  14  having an upper portion  18  and a resilient sole portion  22 . The upper portion  18  of the athletic shoe  14  has a forefoot-enclosing section  26  and a heel-enclosing section  30 . The forefoot enclosing section  26  has a first side  498  and a second side  502  and includes at least one pair of first  506  and second (not shown) L-shaped brackets disposed on the first  498  and second  502  sides. 
         [0117]    The  FIG. 16  embodiment of the removable shoe weight  402  may be attached to the first  506  and second (not shown) L-shaped brackets disposed on the first  498  and second  502  sides of the forefoot-enclosing section  26  of the upper portion  18  of the athletic shoe  14  in the manner previously described and illustrated for  FIGS. 16-18 . 
         [0118]    A final variation of the invention further comprises a plurality of weights  402  of varying heaviness formed to attach to the forefoot-enclosing section of the athletic shoe  14 . Each of the weights includes at least one magnetic insert  76 . 
         [0119]    The variable weight athletic shoe  10  has been described with reference to particular embodiments. Other modifications and enhancements can be made without departing from the spirit and scope of the claims that follow.