Chapter 1
The foam revolution: how bubbles save your joints
Chapter 2
The snap of carbon fiber: mechanical springs underfoot
Chapter 3
Curved soles and aerodynamics: rolling through the wind
Chapter 4
The biomechanical trade-off: speed vs. physical strain
Ch 1 · The foam revolution: how bubbles save your joints
adidas Trapping thousands of tiny bubbles allowed the Villanova shoe to absorb shock, laying the groundwork for modern cushioned midsoles
adidas Aerospace insulation technology now provides lightweight, springy cushioning for elite marathon runners.
Quiz
Approximately what percentage of energy does high-performance Pebax foam return to a runner?
Quiz
Before it revolutionized running shoes, Pebax was primarily developed for which industry?
Fun Fact
Space roots: Nike's ZoomX foam is derived from a material originally used in aerospace engineering for airplane cabin insulation.
Quiz
Which atmospheric gas is most commonly used in its supercritical state to foam high-performance midsoles?
Glossary
eva foam (noun)
A lightweight, flexible copolymer of ethylene and vinyl acetate containing tiny gas bubbles that provide cushioning. In 1975, Brooks introduced the Villanova, the first athletic shoe featuring this cushioning material in its sole.
A lightweight, flexible copolymer of ethylene and vinyl acetate containing tiny gas bubbles that provide cushioning. In 1975, Brooks introduced the Villanova, the first athletic shoe featuring this cushioning material in its sole.
Quiz
What is the maximum allowable sole thickness (stack height) for road racing shoes under World Athletics rules?
Quiz
In what year did World Athletics officially introduce the 40mm stack height limit to regulate super shoes?