What Is General Adaptation Syndrome?

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What Is General Adaptation Syndrome (GAS)? 

General Adaptation Syndrome

General adaptation syndrome (GAS) is a description of the process of how your body responds to stress. The phenomenon was first identified by a scientist named Hans Selye in 1946.

The easiest way to understand GAS is to view it as the different stages of stress and how your body reacts at each stage. GAS occurs in three stages, and each stage is characterized by a unique set of physiological changes that your body undergoes. 

Stages of General Adaptation Syndrome 

General adaptation syndrome occurs in three stages. In each of these stages, your body reacts in different ways. The physiological changes your body goes through during this process can have a long-term negative effect.

Below are the three stages of GAS explained.

Alarm Reaction Stage 

This is the first stage of general adaptation syndrome. During this stage, your body sends a distress signal to your brain. Your brain responds by sending a message to the body releasing hormones called glucocorticoids and adrenaline; these are also known as your “fight or flight” hormones. During the alarm reaction stage, you’ll also experience elevated blood pressure and heart rate levels. 

Resistance Stage 

The resistance stage occurs after the reaction stage. During this stage, your body tries to thwart the changes that occurred during the reaction stage employing the parasympathetic nervous system. It typically occurs when whatever was triggering your stress has stopped.

If you remain stressed, the reaction stage will persist. In the resistance stage, your body begins to lower your blood pressure and heart rate. It also reduces the amount of adrenaline and cortisol being produced.

Your body, however, remains on alert in this stage and can easily switch back to the reaction stage if the stressor persists. At this stage, your body is simply trying to recover from the shock of the alarm reaction stage. 

Exhaustion Stage 

Stress puts your body through a toll, and the exhaustion stage occurs after prolonged stress. You experience this stage after your body has gone through an extended period of stress. Here, even if the stressor persists, your body is too depleted to continue to combat it. This is the riskiest stage of general adaptation syndrome, as you are most prone to developing health conditions here.

Signs of General Adaptation Syndrome 

During each of the three stages of general adaptation syndrome, your body exhibits different signs. 

Alarm Reaction Stage 

During the reaction stage, your body reacts in the following ways. 

  • Elevated blood pressure 
  • Heart rate quickens 
  • Pupils dilate 
  • Senses become heightened 
  • Skin flushes 

Resistance Stage 

If there is persistent stress, in the resistance stage your body may exhibit the following:

Exhaustion Stage 

The exhaustion stage leaves your body feeling unequipped to ward off stress. You are susceptible to developing stress-related conditions at this stage. Your body might exhibit the following symptoms: 

  • Anxiety 
  • Cognitive difficulties
  • Depression 
  • Fatigue
  • Insomnia

Identifying General Adaptation Syndrome 

Hans Selye, a researcher, and scientist came up with the concept of general adaptation syndrome. He used the term to define the physical changes the body goes through when it's stressed. He discovered this while experimenting on lab rats.

In his study, he noticed that the rats went through specific psychological changes during the experiment when exposed to physical stressors like extreme temperatures.

However, many other things could also trigger stress and they include: 

  • Losing a loved one 
  • Getting fired from a job 
  • Going through a breakup 
  • Having a demanding job 

Stress is responsible for general adaptation syndrome occurring. Although Hans Selye has only identified physical stressors in his initial experiment, any type of stress could cause GAS to occur.

During the first stage of general adaptation syndrome, your body goes into “fight or flight” mode. This mode is essential to protect yourself during a stressful or dangerous situation. You get a burst of energy that helps you think more critically and help effectively tackle the stressful situation at hand.

Complications Associated With General Adaptation Syndrome 

While general adaptation syndrome isn’t a condition that needs to be diagnosed or treated, it’s primarily a description of what happens to your body under stress. Being in a stressful state for an extended period can cause medical complications. You could develop a host of physical and medical conditions. Some of the most common conditions that have been linked to experiencing prolonged levels of either physical or mental stress include:

  • Hypertension 
  • Mood and anxiety disorders 
  • Heart disease 
  • Immune suppression

Managing General Adaptation Syndrome 

Finding ways to cope with prolonged stress will help prevent your body from going into the exhaustion stage. The exhaustion stage is the riskiest stage of general adaptation syndrome. During this stage, your immune system is weakened, and you are at an increased risk of developing health conditions such as high blood pressure, strokes, and heart diseases. 

There’s no one way to manage stress. You’ll have to identify your stressors and attempt to get rid of them or minimize them. A few tested and tried techniques people have used to manage stress for centuries include: 

  • Eat a balanced diet: What you eat plays a significant role in how you feel. If you fuel your body with unhealthy foods, it will be ill-equipped to handle stressful situations. 
  • Exercise more regularly: Research shows that exercising regularly can help to reduce your stress levels.If you are new to exercising or don’t like to go to the gym, taking daily walks around your neighborhood is a great way to start moving. 
  • Practice breathing exercises: Taking deep and controlled breaths when in a stressful situation can help you relax and cope better. 
  • Identify your triggers: The first step to managing your stress is identifying what triggers it in the first place. This could be a highly demanding job, communicating with an estranged relative, or going to a specific location. Identifying what triggers your stress can help you get rid of them. 
  • Write down your feelings: Journaling is an often overlooked way of dealing with stress. Writing down your feelings and coming to terms with them can help you cope better. 
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5 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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