General Adaptation Syndrome

General Adaptation Syndrome
Adobe Stock Images

General Adaptation Syndrome (G-A-S) is a basic theory of a living organism’s response to stress. The basic theory suggests that anything that threatens life produces stress, leading to an adaptive responses. General adaptation syndrome describes the physiological changes the body automatically goes through when it responds to stress. We have a basic biological reaction to stress “irrespective of the agent used to produce stress” (Selye, 1951). When stress remains unresolved, stressors lead to disease. 

​Hans Selye and The General Adaptation Syndrome

Hans Selye (1907–1982) was revolutionary in transforming scientific theories on stress. The word ‘stress’ is used in physics to refer to the interaction between a force and the resistance to counter that force. Hans Selye incorporated this term into the medical lexicon to describe the “nonspecific response of the body to any demand” (Tan & Yip, 2018).

​Hans Selye first developed the general adaptation syndrome in 1936. General adaptation syndrome is considered a pioneering modern biological theory, describing the formulation of stress. Many of Selye’s theories associating stress with illness are commonly accepted in the medical field today.

Selye’s theory hypothesizes that “stress is a major cause of disease because of the long-term hormonal changes stress causes in the body.” He further theorized that “the body has a limited supply of adaptive energy with which to deal with stress and that this amount declines with continuous exposure.” He explains that “when there has been trauma, stress levels are chronically high and the body loses its capacity to adapt or recover, leading to adrenal fatigue and exhaustion” (Heller & LaPierre, 2012, Kindle location 1,768).

​A staple of wellness is managing life stress to prevent habitual exhaustion. Habitual exhaustion (burnout) leads to illness and disease.

General Adaptation Syndrome and Good Stress

GAS doesn’t suggest that stress is bad. Selye never suggested life should be stress free. Life is stressful. Survival is earned through successfully navigating problems. Selye believed that “stress is the spice of life,” arising from both pleasant and unpleasant activities. Our goal, then, is not freedom from all stress, but rather to keep stress in manageable portions (Krech, 2012, Kindle location 759).

Selye explained that “the effects of stress depend not only on the magnitude and duration of the stressor, but also on the strategies individuals adopt to cope with it (Heller & LaPierre, 2012, Kindle location 1,772). Effective stress management techniques would minimize the amount of stress (through healthy living) and bolster our ability to cope with the frustrations

Selye’s theory emphasizes an important element for wellness, “excessive stress occurs when the demands made on an organism exceed that organism’s reasonable capacities to fulfill them” (Maté, 2011, Kindle location 575). Growth requires stress in moderation, enough to push change, but not so much that we exhaust and collapse.

General Adaptation Syndrome Stages:

Selye’s General Adaptation Syndrome divides an organism’s reaction of stress into three stages: alarm reaction, resistance, and exhaustion.

Alarm Reaction Stage

The alarm stage is the organisms physiological reaction to the introduction of a stress. You may be familiar with the “fight-or-flight” response. This natural reaction to stress prepares the body to either flee or protect against threats. When exposed to a threat, our heart rate increases, adrenal gland releases cortisol (a stress hormone), and we get a boost of adrenaline to increase energy.

The alarm stage is this initial physiological reaction to stress, knocking us from the calm of homeostatic balance in preparation for survival behaviors.

Resistance Stage

Selye wrote that “stress is an interaction between damage and defense.” The physiological response has “toxic effects” (Selye, 1951). Physiological arousal is necessary for survival but comes at a cost.

The body quickly responds to the physiological changes of the alarm stage to restore homeostatic balance. This response is the resistance stage. Selye explains that most of the physiological changes occurring the alarm stage “disappear or are actually reversed during the stage of resistance” (1951).  

We employ defenses to resolve stress. Selye uses the term “adaptive energy.”  Gabor Maté M.D., explains that “adaptiveness is the capacity to respond to external stressors without rigidity, with flexibility and creativity, without excessive anxiety and without being overwhelmed by emotion” (Maté, 2011, Kindle location 3,904).

The alarm sounds by creating physiological change and we respond to put out the fire, calming our system. However, defenses also come at a cost. In her article on general adaptive syndrome, writer Valencia Higuera lists some signs of the resistance stage as:

  • irritability
  • frustration
  • poor concentration (2018).

These signs indicate we are diverting valuable resources to cope with the stress, leaving limited resources for other important cognitive functions.

Exhaustion Stage

The physiological reactions to stress that appear in the alarm stage, settle in the resistance stage, re-appear in the exhaustion stage. Selye theorizes that “the ability of living organisms to adapt themselves to changes in their surroundings, their adaptability or ‘adaptation energy,’ is a finite quality” (Selye, 1951). Selye explains that “it is as though we had hidden reserves of adaptability, or adaptation energy, throughout the body. . . . Only when all of our adaptability is used up will irreversible, general exhaustion and death follow” (Maté, 2011, Kindle location 3,897).

The modern concepts of burnout and ego depletion share many of the characteristics of the three stages of stress.​

A Few Words by Psychology Fanatic

Certainly, the science of stress has far surpassed Selye’s original theories he established over 70 years ago. However, many of his discoveries remain relevant today. His theory of general adaptation syndrome set off a flurry of new research and new findings. Many books continue to refer to Selye’s stress research in connection with anxiety and stress related diseases. Selye prophesied that his research would only “vaguely” describe a process that later would be better understood. He knew stress research was just entering the “twilight” stage.

Selye didn’t demand that others his work as final but only as the beginning of a fascinating new frontier of science. We can learn from his revolutionary theories, while skeptically examining them against the context of new findings.

Join 50.2K other subscribers


Heller, ​Laurence; LaPierre, Aline (2012). Healing Developmental Trauma: How Early Trauma Affects Self-Regulation, Self-Image, and the Capacity for Relationship. North Atlantic Books; 1st edition

Higuera, Valencia  (2018) What is General Adaptation Syndrome? Healthline. Published 11-6-2018, accessed 11-9-2021.

Krech, Gregg (2012). The Art of Taking Action: Lessons from Japanese Psychology. ToDo Institute Books; 1st edition 

Gabor Maté (2011). When the Body Says No: Understanding the Stress-Disease Connection. Wiley; 1st edition 

Selye, H. (1951). The General-Adaptation-Syndrome. Annual Review of Medicine, 2(1), 327-342.

Siang Yong Tan, MD and A Yip, MS. (2018) ​Hans Selye (1907–1982): Founder of the stress theory.

You May Also Enjoy:

Psychosomatic Disorders. Psychology Fanatic article header image

Psychosomatic Disorders

Psychosomatic disorders are psychological conditions that manifest themselves through physical symptoms with no medical explanation.
Read More
Allostatic Load. Psychology Fanatic article header image

Allostatic Load

Stress has an accumulating impact on our wellness. We lighten the impact of our allostatic…
Read More
Definitions. Psychology Fanatic.

Yerkes-Dodson Law

The Yerkes-Dodson Law proposes that we reach a peak level of performance with an intermediate…
Read More
Mental Health Breaks. Psychology Fanatic article image header

Mental Health Breaks

Life is taxing. We face daily challenges to maintain relationships and succeed. We need mental…
Read More
Burnout. Psychology Fanatic. article header image


We deplete energy through emotional, mental and physical exertions. When we push too hard, for…
Read More

Leave a ReplyCancel reply