Spira's™ patented WaveSpring™ technology may be the most significant advancement ever achieved in the footwear industry.*

WaveSpring™ returns energy with every step.
Ray Fredericksen, president of Sports Biomechanics, Inc. compares typical midsole materials found in many athletic shoes to running in sand. While initially perceived as soft and comfortable, these shoes require the wearer to exert greater effort. Muscles must work harder, causing fatigue and increasing the risk of injury.

Unlike traditional shoe midsoles made primarily of foams, rubber compounds, or polymers, WaveSpring™ technology stores and disburses energy with every step. Testing performed by an independent source reports that 87% - 96% of the energy is returned from the WaveSpring™. This is the highest energy return score for any midsole material ever tested.**

WaveSpring™ is light and compact.
The WaveSpring™ is laterally stable, lightweight, compact, and can easily fit into a typical shoe midsole. The technology is in the heel and forefoot of the shoe. As such, it has the appearance of a normal shoe. Looking from the outside no one will know you have a spring in your step but you!

WaveSpring™ technology will not break down.
Traditional midsole materials work through compression and often breakdown quickly. The WaveSpring™ is mechanical. The spring will outlast the shoe. The wearer will have a "new shoe" feel from the first day it is worn to the last!

"Unlike rubbers and polymers, the springs have an almost infinite fatigue life. The shoe will fall apart before the spring performance degrades."
Popular Mechanics magazine
Shoe Technology Review, July 2003

"I feel it is the first technological advance that has been truly meaningful in the shoe industry in many years."
Donald A. Chu Ph.D., PT, ATC CSCS
Director, Athletic Training & Rehabilitation
Stanford University

*Patented and patents pending.
**Sports Biomechanics, Inc., Michigan State University, May 2001

Experience the WaveSpring™ difference!