A method of differentially tuning a lower limb muscle in a human in need thereof is provided. The method includes placement of at least two calibrated, differential disturbances or protuberances under the human's feet thereby tuning a lower limb muscle.

Articles of footwear can include an adaptive-height sole structure that includes a variable height bladder system. The sole structure can include one or more bladder systems positioned between a midsole and a banking plate. The banking plate can change its relative orientation to the midsole based on an inflation level of the bladder systems.

A dual-layered midsole for footwear includes an internal midsole layer and an external midsole layer, which are coupled to and separated by a Strobel board. The internal midsole layer may compress and expand with the movement of a wearer of an article of footwear including the dual-layered midsole, while the external midsole may provide stability and cushion for the wearer. Materials selected for the internal and external midsole layers may provide tuned viscoelastic properties to different areas of the midsole as a function of midsole layer thickness at each sole area.

A bimodal heel counter apt for a rapid entry and release footwear devices, that includes a flexible hollow hemisphere portion, a heel tab, a secondary heel tab, a back sole base, an anchor system, and dependent fastening elements. The bimodal heel counter and dependent fastening systems are biased to one of two stable positions, which elastically morphs by stored potential energy with applied force from one position to the other, configured to collectively snap a footwear device between an open and closed position, for donning and doffing, or securing the foot as to enable active footwear use.

An apparatus includes a heel section, a mid-foot section, and a toe section. The heel section, the mid-foot section, and the toe section collectively have a geometric shape having a first slope of a polarity along an inner edge of the apparatus from the toe section to the heel section and a second slope of the polarity along the inner edge of the apparatus to an outer edge of the apparatus at the toe section.

A sole structure may include chambers and a transfer channel containing an electrorheological fluid. Electrodes may be positioned to create, in response to a voltage across the electrodes, an electrical field in at least a portion of the electrorheological fluid in the transfer channel. The sole structure may further include a controller including a processor and memory. At least one of the processor and memory may store instructions executable by the processor to perform operations that include maintaining the voltage across the electrodes at one or more flow-inhibiting levels at which flow of the electrorheological fluid the through the transfer channel is blocked, and that further include maintaining the voltage across the electrodes at one or more flow-enabling levels permitting flow of the electrorheological fluid through the transfer channel.

A footwear construction includes a sole assembly including a first midsole platform, a second midsole platform below the first midsole platform, a spring plate disposed between the first and second midsole platforms, and an outsole layer disposed below and joined directly with at least one of the plate, the first and the second midsole platforms. The outsole layer can be substantially the only layer below the plate in the forefoot region of the footwear so an underfoot force engaging the outsole layer is transmitted directly to the plate, which also can have an upward curving, multi-radii transition portion extending from a lowermost portion to a forward most portion of the plate so as to roll a wearer's foot forward into a next stride in a gait cycle of the wearer. The plate can define an aperture. A mounting cap can extend through the aperture and can receive a traction spike.

A method of forming a plate for an article of footwear is disclosed. The method includes applying a first strand portion to a base layer including positioning adjacent segments of the first strand portion to form a first layer on the base layer. The adjacent segments of the first strand portion having a greater density across a width of the plate between a medial side and a lateral side at a forefoot region of the plate than at a midfoot region of the plate and at a heel region of the plate. The method also includes applying at least one of heat and pressure to the first strand portion and to the base layer to conform the first strand portion and the base layer to a predetermined shape.

A sole structure for an article of footwear having an upper includes an outsole, a plate disposed between the outsole and the upper, and a first cushioning layer. The plate includes an anterior-most point disposed in a forefoot region of the sole structure, a posterior-most point disposed closer to a heel region of the sole structure than the anterior-most point, and a concave portion extending between the anterior-most point and the posterior-most point. The concave portion includes a constant radius of curvature from the anterior-most point to a metarsophalangeal (MTP) point of the sole structure. The MTP point opposes the MTP joint of a foot during use. The first cushioning layer is disposed between the concave portion and the upper.

Articles of footwear can include an adaptive-height sole structure that includes a variable height bladder system. The sole structure can include one or more bladder systems positioned between a midsole and a banking plate. The banking plate can change its relative orientation to the midsole based on an inflation level of the bladder systems.