What is Stress?
In 1936, the medical researcher, Hans Seyle, coined the term “stress” as “the non-specific response of the body to any demand for change.” In other words, stress is your reaction to something (the stressor) that threatens to disrupt your internal balance (homeostasis). Your body is always trying to maintain physiological balance because your survival depends on keeping everything from your temperature to your blood sugar within a certain, fairly narrow, range. A stressor, whether it’s harmful (like too little sleep) or beneficial (like a game of touch football with friends), moves your body out of optimal homeostasis, creating stress. The job of your stress response is to both protect you from the stressor and move you back to optimal homeostasis.
More recently, Robert Sapolsky, stress researcher and author of Why Zebras Don’t Get Ulcers, demonstrated that for cognitively complex species like humans, the anticipation of a stressor is enough to cause a stress reaction, even if the actual physical stressor doesn’t materialize. In other words, just stressing about what might happen has the same power to throw you off balance as an actual physical stressor. So dealing effectively with stress requires addressing its psychological as well as physical aspects.