Langabeer said that since methamphetamine is a stimulant, it increases the rate of the body's cardiovascular and respiratory system. When the heart beats faster, energy is created in the body, which heats up internal temperature. The body, Langabeer said, has two automatic ways of dealing with increased stress to the heart: it can make the heart beat faster and it can increase the size of blood vessels. But these coping strategies often fail - both in the case of incredible heat exposure and methamphetamine use.