This is the footprint made by a waffle-sole athletic shoe.
In 1972, William Bowerman, one of the founders of Nike, Inc.
former track coach of University of Oregon, invented the waffle-like
Before this, atheletes can only choose between heavy spiked and flat
Waffle-like soles are light-weight and provide traction. These
became popular in the 1970s.
Source of information:
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