Three predictable stages of the general adaptation syndrome, also known as GAS were described by Hans Selye. In his description, the first stage was called the alarm stage, and this is the stage where there is a burst of energy, which leads to stress. The second stage is called the resistance stage. In the resistance stage, the body either adapt or resist the stressor. In the last stage, also called the exhaustion stage, the body is exhausted as a result of the depletion of energy.
