The first objective of this study was to quantify the initial joint angles and reaction forces of relaxed and braced 5th percentile female and 50th percentile male volunteers in a rigid test buck to validate the alterations made to an existing test buck design. The second objective was to compare the volunteer data to analogous GHBMC models in order to determine if similar initial joint angles and reaction forces were achieved in silico. Six female and six male volunteers experienced low-speed sled tests in relaxed and braced conditions in a rigid test buck, instrumented with load cells at each subject-test buck interface. The test buck, originally designed for 50th percentile males, was modified with spacers for 5th percentile females to obtain similar initial joint angles between sexes. Matched simulations were performed using the GHBMC F05-OS+Active and M50-OS+Active models. The initial positions and force distributions of the female volunteers were very similar to those of the male volunteers for each respective muscle condition, indicating that the test buck design successfully achieved similar initial conditions between sexes. The volunteers and models also had similar initial positions and force distributions when relaxed, with some observed differences when braced. Overall, the results suggest that the models are generally capable of capturing the initial conditions observed in the volunteers for both muscle conditions.