There have been many different definitions of what stress is, whether used by psychologists, medics, management consultants or others. There seems to have been something approaching open warfare between competing definitions: Views have been passionately held and aggressively defended.

What complicates this is that intuitively we all feel that we know what stress is, as it is something we have all experienced. A definition should therefore be obvious…except that it is not.

One problem with a single definition is that stress is made up of many things: It is a family of related experiences, pathways, responses and outcomes caused by a range of different events or circumstances. Different people experience different aspects and identify with different definitions.

Hans Selye (one of the founding fathers of stress research) identified another part of this problem when he saw that different types of definition operate in different areas of knowledge. To a lawyer or a linguist, words have very precise, definite and fixed meanings. In other fields, ideas and definitions continue evolving as research and knowledge expands.

Selye’s view in 1956 was that “stress is not necessarily something bad – it all depends on how you take it. The stress of exhilarating, creative successful work is beneficial, while that of failure, humiliation or infection is detrimental.” Selye believed that the biochemical effects of stress would be experienced irrespective of whether the situation was positive or negative.

Since then, ideas have moved on. In particular, the harmful biochemical and long-term effects of stress have rarely been observed in positive situations.

Now, the most commonly accepted definition of stress (mainly attributed to Richard S Lazarus) is that stress is a condition or feeling experienced when a person perceives that demands exceed the personal and social resources the individual is able to mobilize.

People feel little stress when they have the time, experience and resources to manage a situation. They feel great stress when they think they can't handle the demands put upon them. Stress is therefore a negative experience. And it is not an inevitable consequence of an event: It depends a lot on people's perceptions of a situation and their real ability to cope with it.

This is the main definition used by this site, although we also recognize that there is an intertwined instinctive stress response to unexpected events. The stress response inside us is therefore part instinct and part to do with the way we think.

Responses to Stress
There are two types of instinctive stress response that are important to how we understand stress and stress management: the short-term “Fight-or-Flight” response and the long-term “General Adaptation Syndrome”. The first is a basic survival instinct, while the second is a long-term effect of exposure to stress.

A third mechanism comes from the way that we think and interpret the situations in which we find ourselves.

Actually, these three mechanisms can be part of the same stress response – we will initially look at them separately, and then show how they can fit together.

“Fight-or-Flight”
Some of the early work on stress (conducted by Walter Cannon in 1932) established the existence of the well-known fight-or-flight response. His work showed that when an animal experiences a shock or perceives a threat, it quickly releases hormones that help it to survive.

These hormones help us to run faster and fight harder. They increase heart rate and blood pressure, delivering more oxygen and blood sugar to power important muscles. They increase sweating in an effort to cool these muscles, and help them stay efficient. They divert blood away from the skin to the core of our bodies, reducing blood loss if we are damaged. And as well as this, these hormones focus our attention on the threat, to the exclusion of everything else. All of this significantly improves our ability to survive life-threatening events.

Unfortunately, this mobilization of the body for survival also has negative consequences. In this state, we are excitable, anxious, jumpy and irritable. This reduces our ability to work effectively with other people.

With trembling and a pounding heart, we can find it difficult to execute precise, controlled skills. And the intensity of our focus on survival interferes with our ability to make fine judgments based on drawing information from many sources. We find ourselves more accident-prone and less able to make good decisions.

It is easy to think that this fight-or-flight, or adrenaline, response is only triggered by obviously life-threatening danger. On the contrary, recent research shows that we experience the fight-or-flight response when simply encountering something unexpected.
 
The situation does not have to be dramatic: People experience this response when frustrated or interrupted, or when they experience a situation that is new or in some way challenging. This hormonal, fight-or-flight response is a normal part of everyday life and a part of everyday stress, although often with an intensity that is so low that we do not notice it.

There are very few situations in modern working life where this response is useful. Most situations benefit from a calm, rational, controlled and socially sensitive approach.

The General Adaptation Syndrome and Burnout
Hans Selye took a different approach from Cannon. Starting with the observation that different diseases and injuries to the body seemed to cause the same symptoms in patients, he identified a general response (the “General Adaptation Syndrome”) with which the body reacts to a major stimulus. While the Fight-or-Flight response works in the very short term, the General Adaptation Syndrome operates in response to longer-term exposure to causes of stress.

Selye identified that when pushed to extremes, animals reacted in three stages:

1. First, in the Alarm Phase, they reacted to the stressor.
2. Next, in the Resistance Phase, the resistance to the stressor increased as the animal adapted to, and coped with, it. This phase lasted for as long as the animal could support this heightened resistance.
3. Finally, once resistance was exhausted, the animal entered the Exhaustion Phase, and resistance declined substantially.

Selye established this with many hundreds of experiments performed on laboratory rats. However, he also quoted research during World War II with bomber pilots. Once they had completed a few missions over enemy territory, these pilots usually settled down and performed well. After many missions, however, pilot fatigue would set in as they began to show “neurotic manifestations”.

In the business environment, this exhaustion is seen in “burnout”. The classic example comes from the Wall Street trading floor: by most people’s standards, life on a trading floor is stressful. Traders learn to adapt to the daily stressors of making big financial decisions, and of winning and losing large sums of money. In many cases, however, these stresses increase and fatigue starts to set in.

At the same time, as traders become successful and earn more and more money, their financial motivation to succeed can diminish. Ultimately, many traders experience burnout. We look at this in more detail in our section on burnout.

Stress and the way we think
Particularly in normal working life, much of our stress is subtle and occurs without obvious threat to survival. Most comes from things like work overload, conflicting priorities, inconsistent values, over-challenging deadlines, conflict with co-workers, unpleasant environments and so on. Not only do these reduce our performance as we divert mental effort into handling them, they can also cause a great deal of unhappiness.

We have already mentioned that the most common currently accepted definition of stress is something that is experienced when a person perceives that “demands exceed the personal and social resources the individual is able to mobilize.”

In becoming stressed, people must therefore make two main judgments: firstly they must feel threatened by the situation, and secondly they must doubt that their capabilities and resources are sufficient to meet the threat.

How stressed someone feels depends on how much damage they think the situation can do them, and how closely their resources meet the demands of the situation. This sense of threat is rarely physical. It may, for example, involve perceived threats to our social standing, to other people’s opinions of us, to our career prospects or to our own deeply held values.

Just as with real threats to our survival, these perceived threats trigger the hormonal fight-or-flight response, with all of its negative consequences.

Building on this, this site offers a variety of approaches to managing stress. The navigation bar in the left hand column offers a range of practical methods for managing these stresses by tackling them at source. It also offers some powerful tools for changing your interpretation of stressful situations, thereby reducing the perception of threat.

Pulling these mechanisms together – the integrated stress response…
So far, we have presented the Fight-or-Flight response, the General Adaptation Syndrome, and our mental responses to stress as separate mechanisms. In fact, they can fit together into one response.

The key to this is that Hans Selye’s ‘Alarm Phase’ is the same thing as Walter Cannon’s Fight-or-Flight response.

We can therefore see that mental stress triggers the fight-or-flight response, and that if this stress is sustained for a long time, the end result might be exhaustion and burnout.