Lower extremity injuries are a major concern for military personnel exposed to blast loading in armored vehicles. The primary mechanism of injury during these events has been identified as high‐rate axial loading to the heel through local deformation of the vehicle floor. Hence, heel mechanics play an important role in the load path and overall lower limb response during high‐rate loading events. In this study, rate‐dependent mechanical properties for the human sub‐calcaneal heel pad were determined using a quasi‐linear viscoelastic constitutive model. Tissue samples were characterized up to 45% compression at peak strain rates of 57s‐1, using a ramp and hold test protocol. The results were incorporated into a finite element (FE) model of the lower limb previously developed and validated for automotive impact applications. The modified FE model with updated heel properties demonstrated superior biofidelity over the original model when compared to experimental impact tests performed at blast loading rates on cadaveric specimens;​ correlation and analysis scores increased by 0.37, on average, for force time‐history response. This work constitutes preliminary steps required for the development of an effective and biofidelic modeling tool that may be used for evaluating future systems designed to mitigate injury in underbody blast events.