This study presents a comparative analysis of the Toyota Human Model for Safety (THUMS) in its three latest versions—Version 4, Version 5, and Version 6—using finite element simulations in LS-DYNA. The objective is to evaluate key differences in anatomical accuracy, injury prediction capability, and computational efficiency across these versions. Version 4 offers a highly detailed anatomical structure, including internal organs, which enhances injury analysis. Version 5 introduces active muscle modeling, enabling the simulation of pre-impact occupant postures. Version 6 integrates both features, combining detailed anatomy with muscle activation capabilities for a more advanced human body representation. To assess these differences, three simulation scenarios were developed, examining frontal sled impacts, falls from seated positions, and falls from standing positions.