Modeling gender and anthropometric influence on human response is essential for understanding biomechanical stressors, population task capability, and injury risk. Arbitrary anthropometric musculoskeletal (MSK) models were generated based on gender and anthropometric variables with MSK muscle strength optimized using lower spinal moment generation capacity. Two female (F1, F2) and two male (M1, M2) MSK models were compared using a 300 s Sorensen test simulation for muscle activation, forces, capacity, pain score, and lumbar joint reaction forces and moments. Predicted muscle activation, force, capacity, pain score, reaction shear and compressive force, and reaction pitch moment followed a body size relationship where M2 > M1 > F2 > F1. The anthropometric MSK model generation process created variants that were not simply proportionally scaled versions of the reference model in dimension and strength. The smallest MSK model (F1) exhibited comparatively higher capacity than the other models in agreement with literature.