volunteer kinematics and reaction in lateral emergency maneuver tests it is important to understand human kinematics and muscle activation patterns in emergency maneuvers for the design of safety systems and for the further development of human models the objective of this study was to quantify kinematic behavior and muscle activation in simulated steering tests in several realistic conditions in total 108 tests were performed with 10 volunteers undergoing purely lateral maneuvers at 5 ms2 deceleration or simulated lane change maneuvers at 5 ms2 peak acceleration and peak yaw velocity of 25 s test subjects were seated on a rigid seat and restrained by a 4point belt with retractor driver subjects were instructed to be relaxed or braced and to hold the steering wheel while passenger subjects were instructed to put their hands on their thighs subjects were instrumented with photo markers that were tracked with 3d high speed stereo cameras and with electromyography emg electrodes on 8 muscles corridors of head displacement pitch and roll and displacement of t1 shoulder elbow hand and knee were created representing mean response and standard deviation of all subjects in lane change tests for the passenger configuration significant differences were observed in mean peak of head left lateral displacement between the relaxed and the braced volunteers ie 171 mm 58 n21 versus 121 mm 46 n17 respectively sitting in a relaxed position led to significantly lower muscle activity of the neck muscles it was concluded that significantly more upper body motion and lower muscle activity was observed for relaxed subjects than for braced subjects