Linear and angular accelerations of the human head during heading of a soccer ball

Linear and angular accelerations of the human head were measured during heading of a soccer ball. A set of three tri-axial accelerometers was mounted to the head of each of four adult male subjects. Acceleration measurements (9 signals) were used to estimate the linear acceleration of the mass center, and the angular acceleration of the head. Results were obtained for ball speeds of 9 and 12 m/sec (20 and 26 mph). At these speeds linear accelerations of the head were 158±19 and 199±27m/s² and the angular accelerations were 1302±324 and 1457±297 rad/s². The impact duration was approximately 25 ms. Linear and angular acceleration levels are well below those thought to be associated with traumatic brain injury, but the effect of repeated accelerations at these levels is unknown.