Energy return member for footwear

An article of footwear comprising:

• an upper;
• a sole attached to the upper, the sole including a forefoot region, a midfoot region, and a heel region, wherein the upper and the sole form a foot cavity;
• and
• a resilient member embedded in the sole, the resilient member including a first cantilever arm, a second cantilever arm, a third cantilever arm, a fourth cantilever arm and a central portion, the central portion at least partially positioned in the midfoot region of the sole, the first cantilever arm and the second cantilever arm extending from the central portion into the forefoot region of the sole, the third cantilever arm and the fourth cantilever arm extending from the central portion into the heel region of the sole, the first and third cantilever arms extending along a lateral side of the sole and the second and fourth cantilever arms extending along a medial side of the sole, the resilient member further including at least one indentation extending in a direction transverse to the length of the sole on a side of the resilient member that faces the foot cavity, the at least one indentation configured to promote deformation of the resilient member in response to the force on the sole.

An article of footwear configured for a foot of a human wearer, the article of footwear comprising:

• a sole including a medial side, a lateral side, a forefoot region and a heel region;
• an upper attached to the sole, the upper and sole defining a foot cavity configured to receive the foot;
• and
• a spring plate positioned within the sole, the spring plate comprising:
• a central member positioned posterior to the forefoot region of the sole;
• a first medial arm extending from the central member to the forefoot region of the sole on a medial side of the sole;
• a first lateral arm extending from the central member to the forefoot region of the sole on a lateral side of the sole;
• at least one posterior arm extending from the central member to the heel region of the sole;
• and
• at least one indentation in the first medial arm or the first lateral arm, the at least one indentation extending in a direction transverse to the length of the sole on a side of the spring plate that faces the foot cavity;
• wherein the first medial arm and the first lateral arm are configured to resiliently deform in response to a force on the sole during a stride of the wearer and resiliently recover in response to the force being removed from the sole, the at least one indentation configured to promote deformation of the spring plate in response to the force on the sole.