The term stress has been subjected to numerous definitions and therefore the understanding of what exactly stress is, is somewhat confused.
One of the earliest definitions of stress was put forward in 1926 by Hans Selye. Dr Selye was a Canadian doctor who throughout the 1920’s and 30’s conducted laboratory studies on humans and animals. His work resulted in the first documentation of the hormonal and biological changes that arise in response to stress. Selye concluded that stress is ‘the non-specific response of the body to any demand for change’.
Some researchers, doctors and health care practitioners defined stress as something external for example an important exam or relationship conflicts. For others stress is a description of a physical, biological and neurochemical response such as increased cortisol hormone in the brain, skin rashes, headaches and increased blood pressure and for others still stress is the end result of such bodily changes such as a heart attack.
Due to the confusion and disagreement in the exact definition of stress, Selye made the distinction between stressors (something external that instigates an internal change) and stress (the internal change that can range in severity).
In everyday life, humans are faced with external pressures, stressors, that instigate an internal stress response known as the fight or flight response.
Hans Selye noted: “Without stress, there would be no life” without the fight or flight stress response humans may not have survived the evolutionary pressures that early homosapiens had the capacity to withstand.