Why are there so many different spring configurations?
The WaveSpring configurations (one, two or three springs) are tuned for particular activities. For example, a Spira walking shoe has two large springs (one in the forefoot and one in the heel) for a more bouncy feel and superior cushioning needed for walking or standing all day. However, the running shoes utilize three smaller size WaveSprings (two in the forefoot and one in the heel) to provide more forefoot flexibility while still reducing peak impact forces.
