The parameters of duration, rate of onset and peak acceleration of the sled have been identified by other investigators as determinants of the dynamic and injury response of man. A series of human experiments have been conducted to measure the response of the head and the first thoracic vertebrae to these parameters.

Each subject was run at three conditions defined as high rate of onset-long duration (HOLD), high rate of onset-short duration (HOSD) and low rate of onset-long duration (LOLD) at peak accelerations of 6, 10 and 15G.

Comparison time profiles of angular acceleration, angular velocity and linear resultant acceleration at the head anatomical origin and horizontal linear acceleration at the T 1 origin are presented for 5 to 8 subjects at each of the three peak sled acceleration levels.

Regression coefficients of peak values of the kinematic parameters of onset and duration as defined by the sled profile are developed, as well as coefficients based on similar parameters defined from the profile of linear acceleration at T 1 .

Modeling efforts explaining the mechanism by which onset, duration and peak sled acceleration combined to affect the profiles at T 1 and ultimately the peak values of significant parameters on the head.