In this photo we see the European approach to side impact protection in a sedan based race car. Instead of stiff NASCAR style "ladder bars" the Europeans use compressible foam covered in Kevlar. This way the car is able to absorb some of the impact, in a similar manner to a helmet. The idea is to avoid large G-loading on the driver. One could say the European mantra is that "It's not the crash that kills you, it's the sudden stop".