Bowerman's design inspiration led to the introduction of the so-called "Moon Shoe" in 1972, so named because the waffle tread was said to resemble the footprints left by astronauts on the moon. Further refinement resulted in the "Waffle Trainer" in 1974, which helped fuel the explosive growth of Blue Ribbon Sports/Nike. While Bowerman was experimenting with shoe design, he worked in a small, unventilated space, using glue and solvents with toxic components that caused him severe nerve damage. The nerve damage to his lower legs left him with significant mobility problems; as Kenny Moore notes in his book "Bowerman and the Men of Oregon", Bowerman had rendered himself unable to run in the shoes that he had given the world.