The first Nike shoes were made inside a waffle iron. Bill Bowerman’s first eureka moment for footwear innovation came in 1971, when he and his wife were making waffles for breakfast: It sparked an idea for a grooved pattern on the sole of trainers to help athletes grip running tracks. It spawned the “Nike Waffle Trainer,” patented in 1974 (at the expense of his wife Barbara’s waffle iron.)

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