Patent ID: 8584380

Claim:
An article of footwear comprising: a sole structure; and a self-adjusting stud, the self-adjusting stud including a static cleat and an extendable element, and wherein the static cleat extends downward from a bottom surface of the sole structure, the static cleat has a hole defined therein, the hole having an opening on a bottom of the static cleat, the extendable element includes a shaft and a leaf spring, the shaft extends through the static cleat hole, a lower end of the shaft protruding through the opening, the extendable element is movable between an extended position in which the static cleat and the extendable element have a first combined length and a retracted position in which the static cleat and the extendable element have a second combined length less than the first combined length, and the leaf spring radiates outward from an upper end of the extendable element and biases the shaft to the retracted position.