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Stress is helpful – but if you think it’s not, it’ll mess with your head


Stress seems to be something we are all subject too. In a recent survey by ThoughtLeaders 83% of people said that they had experienced stress that affected their performance at work. We mostly talk about the negative impacts and whilst they are many there is some interesting research that may have us thinking differently about stress and its role in work place performance. Stress is something I’ve been intimately acquainted with. I tend to put a lot of pressure on myself and often end up losing sleep as a result. I also carry my stress in my body; suffering from a tight back, clenched teeth and bloated stomach.  I tell you this not because you need to know my problems but because many people live with these types of symptoms and never associate them with stress.

Good and bad stress

As early as the 1908 the Inverted-U model was created by psychologists Robert Yerkes and John Dodson. The inverted U is also known as the Yerkes-Dodson Law. The model shows the relationship between stress, or arousal, and performance. Imagine an inverted U. According to the model, peak performance is achieved when people experience a moderate level of stress, typically close to the top of the inverted U.

In other words, when we experience too little or too much arousal or stress, performance is impacted, negatively.

The bottom left hand side of the U represents the situation where people are under-challenged. Here it is hard to get motivated to do anything. You will have experienced this, you just can’t get round to writing that report, making the phone call or tidying the office.

At the midpoint we are in Flow, this is the work of Csikzentmihalyi who has studied the experience for many years. He has created a formula for teaching people to enter the Flow state. Simply put it is about getting a balance between the level of perceived challenge in a task and your perceived abilities to carry it out. If challenge is too low, you coast. If it is too high, you go into panic.

Once arousal passes the mid-point there is over-arousal or what we typically mean when we say we are stressed. This begins to also impact performance. Here you are likely to react emotionally, be forgetful and to be poor at making connections. You may suffer from poor sleep.

So the message is: reduce your stress but only to the point of Flow.

How stress hormones work

We have a number of different stress hormones that affect our bodies, but they are not bad all the time – it is the excess that causes the problems. Adrenaline, noradrenaline and cortisol are stress hormones called glucocorticoids that are essential for us to function properly in the face of danger. From an evolutionary point of view the stress response developed to keep us safe – it is the flight, fight, freeze response. These hormones are therefore useful in helping us to learn and form new memories, but with extended stress we can enter a state called cortisol dominance, which negatively affects learning, attention span, and memory.

What each person experiences as stress is individual. What stresses you may be completely different to what stresses your team or partner. In other words, what matters most is not what happens to you, but how you react to what happens to you.

Stress and the Brain

According to Bruce McEwen, a neuro-endocrinologist, stress is in our heads since our brain is responsible for recognising and responding to stressors. The areas that are mainly involved are: the amygdale, the hippocampus, and the prefrontal cortex which works with the hypothalamus to turn on or shut down the production of stress hormones and other automatic responses to over-arousal that is stress, like increased heart rate. But researchers are now learning how stressors can physically alter the brain, which in turn, may impact how we learn, form memories, and even make decisions. The effects are sometimes reversible.

Neurobiologist Tallie Baram  and colleagues looked at how short-term, but acute, stress impacts on the adult brain. They found that the brain produces a different type of stress hormone, called corticotrophin (CRH), in response to short-term stressors, like a very difficult meeting with the board. Just a few hours of CRH exposure was enough to destroy the "delicate balance" between the parts of dendrites that send and receive messages in the synapses.

Fred Helmstetter of the University of Wisconsin found that the hippocampus memory-forming region of the brain actually shrank slightly in rats exposed to chronic stress. This has also been found in patients suffering from post-traumatic stress disorder. The evidence suggests that stress also does nasty things to our brain. In the short term we can overcome the impact with exercise, sleep, as well as a practice of relaxing or meditation. But the prolonged stress that creates damage in the hippocampus does not seem to be completely reversible.

Stress and the Body

The effects of fight or flight don’t only occur in the brain. Our bodies are physically affected by this state. It directs blood flow away from extremities and towards the heart, lungs, legs and back. Historically this was to help us maximize running and fighting, but it reduces fine motor skills dramatically. Also because in this mode the body wants to use all of the available energy for fighting or fleeing, it stops other processes like digestion. This is why we often feel sick during or after high-stress situations.

You may have experienced how fast your heartbeat can get during stressful situations. The fast heartbeat actually sends a signal to the brain’s prefrontal cortex – the executive brain that handles planning, analytical thinking and decision making, and tells it to shut down temporarily and let the limbic brain take over. This has been called the “kill or be killed” section. When we’re in this state, instinct and training takes over from rational thought and reasoning. This is useful if you are running from a tiger but less helpful for your performance review or board meeting.

Stress has been implicated in various health issues, particularly chronic stress that continues over long periods of time. It can lower immune system functioning making us more susceptible to illness, lead to high blood pressure and heart disease, cause everyday aches and pains, weight gain, sleep loss, lowering of sex drive and skin conditions like hives or eczema. Dr. Vivian Diller, summed it up this way “It’s very possible that if you have a life filled with that constant stress, little by little the body is breaking down.”

We have made a short video animated video here.

But then there is other research ….

In resent research the whole belief system about stress is being called into doubt. Scientists at University of Wisconsin-Madison say that thinking that stress is bad for you is … really bad for you. An eight year study found 182,000 people died prematurely from the belief that stress was bad for them. Kelly McGonigal estimates that would make stress the 15th largest cause of death in the United States.

In other research scientists looked at what might happen if we change the way we think about stress, if we re-reappraised the feelings associated with stress and thought about them as helpful.  Treating common stress responses as a positive might even be good for the heart. For example thinking of butterflies in the stomach as a signal you are ready to make a presentation or that feeling nervous means you are excited. Re-appraisal suggests individuals think of stress as a tool that helps maximize performance. By reframing the meaning of the physiological signals that go with stress the link between negative experiences and poor physiological responses was broken. The researchers found this had benefits for physiological reactions, attention, and performance.

In other research it was found that spending time socialising and caring for people can also create resilience to stress and reduced death rates of those who experienced stress.

“The harmful effects of stress on health are not inevitable,” McGonigal says. “How you think and how you act can transform your experience of stress. When you choose to view your stress response as helpful, you create the biology of courage. And when you choose to connect with others under stress, you can create resilience.” You can see her excellent TED talk here.

The implications for HR are important on several levels. The personal: what are your beliefs about stress? The organisational: how are you talking about stress and responding to it? And from a performance view point:  how are you helping people reframe their experience?

8 Responses

  1. Late-breaking news…..

    … of 20 years ago! Dip into the archives to read about 'allostatic load', and at least be thankful that this message has now been heard. Lizardman's corrosive fluid isn't a fanciful notion, read up on Tumour Necrosis Factor TNF-α and be very, very afraid.

  2. Excellent

    Excellent article,


    At the end of the day …it's all about the individual. What makes one person stressed may not apply for someone else.

    Understanding the difference pressure , Eustress and Distress is highly important.

    Resilient Regards




  3. you are right

    We also need to keep in mind the way we react to situations. teaching people to re-frame events can be very powerful in managing stress and other negative events.

    I am currently getting very excited by the work of Barbara Fredrickson on positivity and the benefits that could be derived for organisations. Mybe an article on that at a future date

  4. Pressure can be good for you

    We have to learn to differentiate between pressure and stress.  There are countless people out there who can't (or won't…) perform without pressure.  Deadlines have a remarkable way of focussing the mind.  A ticking clock is an amazing incentive, in fiction and in reality.

    Stress is the redline on the dial.  Dip into it briefly, if you must, for that little bit of extra power, but if you try to keep it there permanently, things break.  The damage to the hippocampus you refer to is caused because the stress chemicals aren't just neuro-transmitters.  They're also mild corrosives.  You bathe anything in a corrosive fluid for long enough, you'll ruin it.

    I'm going to be sharing your excellent article with lots of people, because it gets this message across – when you truly stress someone long-term, you're not just tiring them out, or running them down, you're actually causing brain damage.  And that's never going to look good on a 'mission statement'…

  5. Stress can power you through the day

    I like the "inverted U" model and find this very true for myself. Stress can sometimes keep me focused on the task at hand and I find that my productivity increases when I'm in that balanced zone of stress-levels. 

  6. Stressing the point

    Yes, good article.  The UK plc has become psychotic about stress and tend to ignore some of the positive aspects of stress.

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Jan Hills


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