Impact attenuating/spring systems may include first and second body
portions and at least one spring member at least partially included
between the body portions. The spring member(s) may substantially enclose
and/or be pivotally engaged with the body portion(s). The components of
the impact attenuating and spring element may be arranged such that when
a force is applied to the body portion(s), the spring member(s) will
exert a counter force to urge the impact attenuating and spring element
back toward its original orientation. The spring members may include one
or more polymeric element that stretches under a tensile force. The
impact attenuating and spring elements may be included in a piece of
footwear or other device in a manner such that a user or a retailer (or
others) can select an appropriate spring member (or portion thereof),
e.g., depending on characteristics of the user or the intended use.