The objective of this study was to assess an active finite element human body model’s capability of capturing variability in occupant bracing. This study used the Global Human Body Models Consortium midsizemale simplified occupant model with active musculature. This model uses a PID-controlled muscle activation strategy with joint angles as control variables. The physiological cross-sectional area (PCSA), reaction delay, and PID-controller reference joint angles were varied to assess their effect on model response. A total of 56 simulations were carried out. Data from five 50th-percentile male volunteers in braced muscle states were used to compare the model performance. Peak forward excursions for various body markers, reaction forces, and average CORA scores were extracted from each simulation and were compared against experimental data. The model was able to capture the variation in occupant bracing by varying PCSA and reference joint angles in the model. The effect of reference joint angle on reaction forces, peak forward excursions, and CORA score was larger than that of PCSA and reaction delay and was statistically significant, making it a better choice. This study provides novel methods and models to capture variation in occupant bracing, which will be useful for studying its effect on injury risk in vehicle crashes.