05625964 is referenced by 144 patents and cites 158 patents.

An athletic shoe has a sole with a rearfoot strike zone segmented from the remaining heel area by a line of flexion which permits articulation of the strike zone during initial heel strike of a runner. The line of flexion is located to delimit a rearfoot strike zone reflecting the heel to toe running style of the majority of the running population. In addition to allowing articulation of the rearfoot strike zone about the line of flexion, the sole incorporates cushioning elements, including a resilient gas filled bladder, to provide differential cushioning characteristics in different parts of the heel, to attenuate force applications and shock associated with heel strike, without degrading footwear stability during subsequent phases of the running cycle. The line of flexion may be formed by various ways including a deep groove, a line of relatively flexible midsole material, and a relatively flexible portion of a segmented fluid bladder.

Title
Athletic shoe with rearfoot strike zone
Application Number
38950
Publication Number
5625964
Application Date
June 7, 1995
Publication Date
May 6, 1997
Inventor
Lester Q Lee
Gaston
OR, US
Thomas McGuirk
Portland
OR, US
Joel L Passke
Portland
OR, US
David M Forland
Battle Ground
WA, US
Michael T Donaghu
Portland
OR, US
Robert J Lucas
Portland
OR, US
Gordon A Valiant
Beaverton
OR, US
Robert M Lyden
Aloha
OR, US
Agent
Banner & Witcoff
Assignee
Nike
OR, US
IPC
A43B 13/20
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