Knit shoes with elastic region

1. A shoe, comprising:

a sole defining a tread surface and a top surface opposite the tread surface;

an upper portion attached to the top surface of the sole and cooperating with one or more additional components of the shoe to define a cavity, and comprising:

an elastic region at least partially surrounding an opening into the cavity and defining at least a portion of a perimeter of the opening, the elastic region having a first elasticity; and

a structural region at least partially surrounding the elastic region and having a second elasticity that is less than the first elasticity; wherein:

an exterior surface of the upper portion is defined by a continuous knit textile comprising eucalyptus fiber;

the upper portion defines a boundary between the elastic region and the structural region;

in a first part of the elastic region, the elastic region has a first ribbed knit pattern defining ribs that extend from the boundary toward the perimeter of the opening; and

in a second part of the elastic region, the elastic region has a second ribbed knit pattern, different from the first ribbed knit pattern, the second ribbed knit pattern defining:

a first set of ribs, each rib of the first set of ribs extending from the boundary to the perimeter of the opening; and

a second set of ribs, each rib of the second set of ribs extending from the boundary to a position between the boundary and the perimeter.

2. The shoe of claim 1 , wherein:

the cavity is adapted to receive a wearer's foot;

the upper portion defines a first portion of an interior surface of the cavity;

the shoe further comprises:

a heel lining attached to the upper portion and positioned along a first part of the interior surface, at least a portion of the heel lining positioned along a portion of the elastic region;

a toe lining attached to the upper portion and positioned along a second part of the interior surface;

an insole positioned within the cavity and defining an insole surface configured to contact a bottom of the wearer's foot; and

a strobel attached to the upper portion and the sole and positioned between the insole and the sole; and

the portion of the elastic region along which the heel lining is positioned has a third elasticity that is less than the first elasticity.

3. The shoe of claim 2 , wherein the heel lining extends around the perimeter of the opening and along the exterior surface of the upper portion.

4. The shoe of claim 1 , wherein:

the sole defines:

a forward section defining a front tip of the shoe; and

a rear section defining a rear tip of the shoe;

in an unworn configuration, the tread surface of the sole is substantially continuously curved between the front tip and the rear tip.

5. The shoe of claim 4 , wherein:

in the unworn configuration:

the elastic region exerts a first elastic force on the structural region and the sole; and

the tread surface of the sole is substantially continuously curved between the front tip and the rear tip at least partially as a result of the first elastic force; and

in a worn configuration, the elastic region exerts a second elastic force on the structural region and the sole that secures the shoe to a wearer's foot.

6. The shoe of claim 1 , wherein the sole comprises sipe features along the tread surface.

7. The shoe of claim 1 , wherein:

a distance between the perimeter of the opening and the boundary is greater than 1 centimeter.

8. A shoe, comprising:

a sole defining a tread surface and a top surface opposite the tread surface;

an upper portion attached to the sole and defining an exterior surface formed from a continuous knit textile, the upper portion comprising:

an elastic region comprising an elastic polymer and defining an opening in the upper portion;

a structural region at least partially surrounding the elastic region and comprising eucalyptus fiber, wherein:

the upper portion defines a boundary between the elastic region and the structural region;

in a first part of the elastic region, the elastic region has a first ribbed knit pattern defining ribs that extend from the boundary toward a perimeter of the opening; and

in a second part of the elastic region, the elastic region has a second ribbed knit pattern, different from the first ribbed knit pattern, the second ribbed knit pattern defining pairs of adjacent ribs, each pair of adjacent ribs comprising:

a first rib extending from the boundary to the perimeter of the opening; and

a second rib extending from the boundary to a position between the boundary and the perimeter.

9. The shoe of claim 8 , wherein:

in the first part of the elastic region, each of the ribs extends from the boundary to the perimeter of the opening.

10. The shoe of claim 9 , wherein the second part of the elastic region is located along a portion of the perimeter of the opening that defines a curve of at least 100 degrees.

11. The shoe of claim 9 , wherein:

a width of the elastic region is defined by a distance between the boundary and the perimeter; and

the width of the elastic region is at least 1.5 centimeters around an entirety of the perimeter.

12. The shoe of claim 8 , wherein:

the first part of the elastic region has a first elasticity; and

the second part of the elastic region has a second elasticity.

13. The shoe of claim 8 , wherein:

the upper portion further defines an interior surface opposite the exterior surface; and

the shoe further comprises at least one of a heel lining or a toe lining attached to the upper portion and positioned along the interior surface.

14. The shoe of claim 8 , wherein the structural region further comprises a thermoplastic material bonded to the eucalyptus fiber.

15. The shoe of claim 8 , wherein the continuous knit textile comprises:

an outer layer defining at least a portion of the exterior surface of the upper portion; and

an inner layer defining at least a portion of an interior surface of the upper portion.

16. A shoe, comprising:

a sole defining:

a front tip of the shoe;

a rear tip of the shoe;

a front lobe having a first width that continuously increases along a first path extending from the front tip to a first maximum width location;

a rear lobe having a second width that continuously increases along a second path extending from the rear tip to a second maximum width location;

a tread surface extending between the front tip and the rear tip, and comprising:

a forward section extending from the front tip of the shoe to the first maximum width location; and

a rear section extending from the rear tip of the shoe to the second maximum width location; and

an intermediate section between the forward section and the rear section; and

a top surface opposite the tread surface; and

an upper portion attached to the top surface of the sole, the upper portion comprising:

an elastic region defining an opening into a cavity of the shoe, and extending around a perimeter of the opening, the elastic region configured to exert an elastic force on the sole; and

a structural region at least partially surrounding the elastic region; wherein:

in an unworn configuration in which the shoe is positioned on a planar surface, the forward section and the rear section are elevated from the planar surface;

the upper portion defines a boundary between the elastic region and the structural region;

in a first part of the elastic region, the elastic region has a first ribbed knit pattern defining ribs that extend from the boundary toward the perimeter of the opening; and

in a second part of the elastic region, the elastic region has a second ribbed knit pattern, different from the first ribbed knit pattern, defining:

a first set of ribs, each rib of the first set of ribs extending to a first distance from the boundary and toward the perimeter of the opening; and

a second set of ribs, each rib of the second set of ribs extending to a second distance, less than the first distance, from the boundary and toward the perimeter of the opening.

17. The shoe of claim 16 , wherein:

in the unworn configuration:

the forward section defines a first substantially continuous convex curve; and

the rear section defines a second substantially continuous convex curve; and

in a worn configuration:

substantially all of the intermediate section of the tread surface contacts the planar surface.

18. The shoe of claim 16 , wherein the elastic force exerted by the elastic portion elevates the forward section and the rear section from the planar surface.

19. The shoe of claim 16 , wherein at least a portion of the forward section is elevated from the planar surface by at least 3 centimeters.

20. The shoe of claim 16 , wherein each rib of the second set of ribs is positioned between a pair of ribs of the first set of ribs.