Can you explain this in Physics Terms?

".....some 1969 Ford models will have collapsible, impact-absorbing front ends as a safety feature... the general idea was to construct the front end so that it would, in case of a head-on collision crumple and shorten by 24 inches. Through an optimum setup of framing, wheels, fenders, hood, engine and other compnents. Ford would like it so that it collapses in a pre-arranged form. This may sound like a small comfort, but it could extend the duration of the typical collision from 90 milliseconds to 125 milliseconds, cut impact forces by 20% to 30%, and thus reduce penger injuries."