How fast do the fastest nerve signals travel along the human body's most heavily insulated nerve fibers, in km/h? (100 km/h ≈ 62 mph)

Answer

430 km/h

Your fastest nerves outpace a Formula 1 car, thanks to fatty myelin insulation that lets signals leap between gaps in the wrapping. Slow, unmyelinated pain fibers crawl along at jogging speed — which is why you can pull your hand off a hot pan before the full 'ow' arrives.

Source: Guyton and Hall Textbook of Medical Physiology