ABSTRACT
Injury is caused by energy transfer to the body by an impacting object. It occurs when sucient 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. e risk of injury is inuenced by the object’s shape, stiness, 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. e torso is viscoelastic, so reaction force increases with the speed of body deformation.
