Pre-crash braking and low-severity frontal crash events occur at low speeds and over long durations, giving occupants enough time to potentially brace prior to impact. Active human body models can capture the effects of muscle activation on occupant response during these low-severity events, but must be validated with relevant volunteer data. The purposes of this study were to quantify the occupant kinematic responses of braced 5th percentile female and 50th percentile male volunteers in low-speed frontal and frontal-oblique sled tests, and to compare to matched relaxed tests. Six 5th percentile female and six 50th percentile male volunteers experienced multiple low-speed frontal and frontal-oblique sled tests consisting of two pulse severities (1 g and 2.5 g) and two muscle conditions per pulse severity (relaxed and braced). The volunteers’ kinematic responses were quantified using a 3D Vicon motion capture system. Forward, lateral, and vertical excursions were compared between demographic groups and muscle conditions. Minimal kinematic differences were observed between females and males for the braced tests. Pre-impact bracing resulted in decreased kinematic responses for all volunteers compared to the relaxed tests.