Nike co-founder Bill Bowerman. Nike Nike's first pair of running shoes was inspired by waffles.

Nike co-founder Bill Bowerman was having breakfast with his wife one morning in 1971 when it dawned on him that the grooves in the waffle iron she was using would be an excellent mold for a running shoe, The Atlantic reports.

Bowerman, who was a track and field coach at the time, had been searching for a way to make shoes lighter and faster, according to The Oregonian.

Oregon's Hayward Field, where he worked, was transitioning to an artificial surface and "Bill wanted a sole without spikes that could grip equally well on grass or bark dust."

He was talking to his wife about this conundrum over breakfast, when the waffle iron idea came into play.

"I picked out a couple pieces of jewelry and things that had stars on them, or things that we thought would indent or make a pattern on the soles," Bowerman's wife, Barbara, told Nike historian Scott Reames in an interview he conducted for the company in 2006, The Oregonian reports. "We were making the waffles that morning and talking about (the track). As one of the waffles came out, he said, 'You know, by turning it upside down — where the waffle part would come in contact with the track — I think that might work.' "So he got up from the table and went tearing into his lab and got two cans of whatever it is you pour together to make the urethane, and poured them into the waffle iron."

The rubber mold inspired Nike's first shoe, the Waffle Trainer, which debuted in 1974. The shoes looked like this:

Note how the soles look similar to the grooves of a waffle iron.

Four decades later, Nike is a global sneaker powerhouse with $28 billion in annual sales. And the company still makes Waffle Trainers.

Here's what today's version looks like: