Interchangeable midsole system

1. A shoe, comprising:

an upper adapted to receive a foot;

an outsole secured to the upper, the outsole including a ground engaging surface, and a surface defining at least one aperture extending therethrough; and

a midsole which, in a mounted position, is removably positioned in the upper, the midsole including at least one projection extending through the at least one aperture formed in the outsole such that a portion of the at least one projection is exposed and accessible from a bottom of the shoe and application of a force to said portion displaces the midsole from said mounted position for removal of the midsole from the shoe, and further wherein in the mounted position the at least projection is held within the at least one aperture to secure the midsole to the outsole,

wherein the midsole includes a plurality of support portions in heel and forefoot areas of the midsole, and the heel and forefoot area are removed together upon removal of the midsole.

2. The shoe according to claim 1 , wherein the at least one projection extends from a bottom surface of the heel area of the midsole.

3. The shoe according to claim 2 , wherein at least one of the plurality of support portions is formed from a gel material and another of the plurality of support portions is formed from a non-gel material.

4. The shoe according to claim 3 , wherein the midsole includes a first gel support portion located in the heel area, and a second gel support portion separate from the first, located in the forefoot area of the midsole.

5. The shoe according to claim 4 , wherein the second gel support portion extends from a midfoot area of the midsole to a toe area of the midsole.

6. The shoe according to claim 4 , wherein the first and second gel support portions are separated by the non-gel material support portion.

7. The shoe according to claim 4 , wherein the midsole includes a side wall portion extending upwardly from at least part of a peripheral region of the bottom surface, and wherein the first gel portion extends at least partially along the side wall in the heel area of the midsole.

8. The shoe according to claim 7 , wherein the first gel portion extending along the side wall extends asymmetrically in the heel area such that a greater area of the first gel portion is positioned on an outer lateral side compared to an inner medial side.

9. The shoe according to claim 6 , wherein the non-gel support portion comprises thermoplastic polyurethane.

10. The shoe according to claim 6 , wherein the non-gel material support portion is formed in an arch area of the midsole and extends along a portion of the bottom surface of the midsole and also along a portion of a side wall of the midsole.

11. The shoe according to claim 2 , wherein at least one of the plurality of support portions comprises a foam material and another of the plurality of support portions comprises a non-foam material.

12. The shoe according to claim 11 , wherein the midsole includes a first foam support portion located in the heel area and at least one foam support portion located in a forefoot portion of the midsole.

13. The shoe according to claim 11 , wherein the non-foam support portion extends in a longitudinal direction of the midsole from an area at or near the projection to an area at or near a toe portion of the midsole.

14. The shoe according to claim 13 , wherein the non-foam support portion comprises carbon fiber.

15. The shoe according to claim 12 , wherein the midsole includes a side wall portion extending upwardly from at least part of a peripheral region of the bottom surface, and wherein the first foam support portion extends asymmetrically at least partially along the side wall in the heel area of the midsole.

16. The shoe according to claim 1 , wherein the shoe includes a first and second shoe, the first shoe including a first midsole and the second shoe including a second midsole, and

wherein at least one of the plurality of support portions for the first midsole is different from at least one of the plurality of support portions for the second midsole.

17. The shoe according to claim 1 , wherein the outsole includes a support plate defining the aperture, the support plate formed of a different material than the ground engaging surface of the outsole.

18. The shoe according to claim 17 , wherein the ground engaging surface of the outsole is located a first distance below a bottom surface of the support plate, and in the mounted position, the projection extends a second distance below the bottom surface of the support plate, with the first distance being greater than the second distance, such that in the mounted position a lowest portion of the projection extends below the bottom surface of the support plate but is above the ground engaging surface of the outsole.

19. The shoe according to claim 1 , wherein the shoe is a tennis shoe.

20. The shoe according to claim 1 , wherein the outsole includes a ground engaging surface and a recessed portion that is recessed from the ground engaging surface, and further wherein the aperture of the outsole extends from a top surface of the outsole, through the outsole and into the recessed portion;

wherein in the mounted position, the projection extends through the aperture and into the recess, such that a portion of the projection is exposed in said recess and said projection is accessible by way of the recess to be urged by hand to remove the midsole from the mounted position; and

wherein in the mounted position, the projection is exposed within said recessed portion and is spaced from said ground engaging such that when a user wears and uses the shoe on a ground surface, the lowermost part of the projection is maintained spaced from the ground surface.

21. The show of claim 20 , wherein the outsole includes a support plate, wherein said aperture extends through the support plate, and wherein the midsole is positioned above the support plate; and

wherein the midsole includes a support portion formed with a gel material disposed above said support plate in the mounted position, and the projection extends from said support portion within a region comprising said gel material.

22. The shoe of claim 21 , wherein the support plate is formed of carbon fiber.