ABSTRACT
Injury is caused by energy transfer to the body by an impacting object. It occurs when sufficient force is concentrated on the chest or abdomen by striking a blunt object, such as a vehicle instrument panel or side interior, or being struck by a baseball or blunt ballistic mass. The risk of injury is influenced by the object’s shape, stiffness, point of contact, and orientation. It can be reduced by energy absorbing padding or crushable materials, which allow the surfaces in contact to deform, extend the duration of impact, and reduce loads. The torso is viscoelastic, so reaction force increases with the speed of body deformation.
