Spira - Spira - Women's Athletic

Zappos.com is proud to offer Spira - Women's Athletic: Spira is a young company that is gaining national attention with its remarkable athletic running and walking shoes. The company is premised upon a proprietary unique shoe technology called WaveSpring. Energy that is otherwise lost to the ground is recycled to the wearer, providing a remarkable combination of cushioning and energy return. Spira makes it easier to stand, walk, run and compete without the stress and fatigue associated with traditional shoe midsole materials. Heel and forefoot spring configurations are engineered for specific activities to meet individual needs. Sport Biomechanics, Inc. tested the WaveSpring technology and found it had the highest return of energy of any shoe technology they have ever tested 87-96%.