What Are Spring-Loaded Shoes?
Anyone who likes to run, jog or hike knows that eventually their feet and joints will get sore and tired. A good pair of shoes can make all the difference, and many are turning to the spring-loaded varieties.
A variety of spring-loaded shoes exist, including versions from name brands such as Nike and Spira. These shoes promise to decrease fatigue and strain on the feet and joints and increase the amount of time that individuals can walk, run or jog before they become tired.
The concept behind spring-loaded shoes is energy return. The springs in the foot bed return more than 90 percent of the energy used in each step to the user. This energy, which would have otherwise simply been lost on the ground, is used as propulsive energy.
Spring-loaded shoes also reduce stress and fatigue on the feet by returning otherwise dispersed energy from the downward force of the step back to the individual. This means that there is less recovery time for each step and reduced impact on feet.
How They Work
The springs inside the shoes are simple, absorbing shock from each step and redirecting the energy. The shoes are usually cushioned with injection-molded EVA foam or a similar substance to increase comfort. Unlike foam, air and gel insoles, the springs will not break down or wear out.
Banned for Track and Field
The USA Track and Field governing body has banned spring-loaded running shoes from competition due to the unfair advantage they give to athletes.