A ski binding heel employs a low-mass, spring-loaded interface between the heel and/or toe release mechanisms of the heel and or toe pieces of the binding and the ski boot, i.e., fast-response heel and toe cups. The low mass or lightweight fast-response heel and toe cup interfaces follows the dynamics of the ski to retain the boot during events that could cause inadvertent release (IR) in a conventional release binding. A biased, or spring loaded member engages, the boot heel/toe for mitigating loads and for absorbing sub-injury loads and compensating for movement between the boot and ski. The spring loaded members are biased toward the boot heel and toe for absorbing loads and compensating for displacements that might otherwise result in an inadvertent release. The spring loaded toe/heel cups permit movements of the boot relative to the ski flexing and counter flexing that might have otherwise resulted in an IR.