Stress & Relaxation
A brief definition of stress
Stress is the experience the body goes through when responding to events and situations that cause physical or mental tension. The connotations of stress and tension lead us to think that these would cause negative effects on the body, but not all stress is bad. ‘Eustress’ is the term for positive stress and ‘distress’ is the term for negative stress. Stress is biologically fundamental for us as human beings to deal with emergency situations, and is what we’re most dependent upon for our survival instincts. The reaction here is referred to as the ‘fight or flight’ response which is generated by the sympathetic nervous system and was first explained by Walter Bradford Cannon in 1915. This acute reaction is usually successfully dealt with by the body in the short term. When the body takes longer to recover, the phase can become chronic so can become harmful to the body.
Hans Selye developed the general adaptation syndrome (GAS) to describe how organisms respond to stress;
‘GAS is characterized by three phases: a nonspecific mobilization phase, which promotes sympathetic nervous system activity; a resistance phase, during which the organism makes efforts to cope with the threat; and an exhaustion phase, which occurs if the organism fails to overcome the threat and depletes its physiological resources.’ 
The response in the body stimulates the adrenal glands to produce the hormones; cortisol, adrenaline and noradrenaline. The body reacts so that the heart beats faster, the lungs work harder, digestion slows down, the bladder relaxes, the pupils dilate, the liver releases glucose, muscles contract and even the mouth becomes dry. So practically all the body’s systems are affected including the respiratory, endocrine, nervous, cardiovascular, musculoskeletal and the digestive (gastrointestinal) system.
The difference between healthy and unhealthy levels of stress
There are many examples of how we experience stress in our everyday lives; just crossing the road, driving or dealing with difficult people causes an elevated level of stress. Certainly ‘eustress’ can be beneficial to help us perform well at work and motivate us to be active and alert. It also enables us to be creative and focussed and can even help us to overcome our fears enabling us to grow as individuals.
Sometimes we can trigger the stress response and not even be aware of it but by skipping meals, not getting enough sleep, over exercising and working long hours, we are physically taxing our bodies. As with modern lifestyles, we get used to these habits and having lights on all the time and being surrounded by various noises and distractions. These things all lessen our ability to relax and replenish ourselves at the end of a busy day.
Some people who do look after themselves physically; get plenty of exercise, are mindful of their diet and get to bed early, may experience stress emotionally by being constantly worried, anxious or depressed for some reason. The more obvious triggers that we tend to associate ‘distress’ with include; bereavement, divorce or breakup, moving house, financial worries or any kind of abuse or trauma. However, the body doesn’t differentiate between these behaviours and releases hormones from the adrenal glands as described in the ‘fight or flight’ response. A series of physiological reactions then occur. How often and how long they last, can have a significant impact our health.
The difference between the aforementioned types of stress is dependent on the individual’s perception of the experience.
Examples of long term, unhealthy effects of stress on the mind and body
Let’s first look at the common effects that stress can have on the body:
‘Common effects of stress on your body;
Muscle tension or pain
Change in sex drive
Common effects of stress on your mood;
Lack of motivation or focus
Irritability or anger
Sadness or depression
Common effects of stress on your behaviour;
Overeating or under eating
Drug or alcohol abuse
Exercising less often’ 
This illustrates how holistically stress can affect the body as well as the mind. If left unattended for a long period of time, this chronic, long term ‘distress’ means the body is trying to manage a consistently higher heart rate and blood pressure. This can lead to more serious health problems such as hypertension, heart disease, heart attack or stroke.
Signalled from the hypothalamus in the brain, the body also produces an elevated amount of cortisol from the adrenal glands which affects the body’s endocrine and nervous systems. Over a period of time this can damage the body’s immune system as the liver repeatedly produces more glucose (a blood sugar) that provides the body energy for the ‘fight or flight’ response. In most people, the body is able to reabsorb this extra energy but for those whose body’s are unable to reabsorb it, they could develop type two diabetes.
For the body to endure the ‘fight or flight’ response, the immune system is suppressed so if such levels of ‘distress’ persist, this can lead to ‘adrenal fatigue’. In this state, the adrenal glands become so exhausted they no longer produce hormones such as adrenaline, DHEA and testosterone which are required to help keep the body in a healthy state of homeostasis. With the immune system so run down and now unable to heal itself, it may be vulnerable to developing an autoimmune condition such as IBS, rheumatoid arthritis and lupus, hashimotos, type two diabetes or muscular sclerosis.
The body’s respiratory system may otherwise be affected as stressful situations cause the individual to breathe harder. Usually the body can deal with this but in certain cases a panic or asthma attack can be induced.
With so many areas of the body affected, as illustrated below, it’s important to find techniques to help prevent such levels of ‘distress’ in the body persisting and recurring.
How does the body respond to deep relaxation?
During deep relaxation, the body elicits the exact opposite reaction of what is triggered by the ‘fight or flight’ response of the sympathetic nervous system. The parasympathetic system is now activated so the heart beats slower, blood pressure is reduced, breathing slows down, digestion is activated, nutrients are better absorbed, the mind is quietened, muscles start to relax and energy begins to be restored.
Herbert Benson M.D., author of The Relaxation Response acknowledges the ‘fight or flight’ discovery of Walter B Cannon and denotes how valuable this finding was at the time. He then describes how relaxation can be ‘imbued’ by the body as a survival technique;
‘Regular elicitation of the Relaxation Response can prevent, and compensate for the damage incurred by frequent nervous reactions that pulse through our heats and bodies.’ 
Leslie Carr, editor of www.thedoctorwillseeyounow.com, wrote an article on how relaxation can bring about positive genetic changes and shared the following findings;
‘The genes affected by relaxation produce proteins involved in energy metabolism and inflammation pathways. The expression of genes involved in insulin pathways was also significantly altered. In particular, pathways controlled by activation of a protein called NF-κB – known to have a prominent role in inflammation, stress, trauma and cancer – were suppressed in people who had achieved a relaxation response.’ 
What are the benefits of yoga relaxation techniques?
There are many positive effects that yogic relaxation can bring the mind and body. As we’ve discussed, when the heart rate and breathing slow down, blood pressure is reduced so the risk of hypertension, heart disease and stroke are also decreased.
A lifestyle free of unnecessary levels of ‘distress’ will maximise the body’s immune system. For those already suffering from an autoimmune condition, a regular relaxation practice will optimise their chances of managing their daily symptoms. Part of the reason for this is that relaxation stimulates the vagus nerve which increases vagal tone.
As with many heart conditions and autoimmune conditions, medication is taken to control them which may have certain side effects. There are no harmful side effects with yoga relaxation.
It also helps develop the habit of rhythmic breathing from the diaphragm rather than from the chest. One can learn to adopt the most beneficial use of the body to breathe.
Cortisol can increase the body’s appetite and cravings for comfort foods which if consumed excessively, can lead to obesity. During relaxation, cortisol isn’t released so the appetite remains normal. Therefore a healthy body, with minimal levels of stress, that consumes a healthy diet is more likely to be in control of their appetite.
Amygdala is a small section of the brain responsible for responding to the body’s emotions, survival instincts, and memory. Research shows that it enlarges when the body undergoes chronic stress but is reduced when mindfulness exercises are practiced;
‘MRI’s of the brain after regularly practicing mindfulness exercises have shown the reduction in size of the amygdala.’ 
Muscle tone can be brought to a minimum in deep relaxation techniques such as yoga nidra, reconditioning the mind and helping to reverse any tension or anxiety. Anyone who actively practices yoga relaxation is likely to benefit from improved levels of concentration and focus, enabling them to deal with everyday ‘stressful’ situations with a more calm and balanced approach. This in turn helps reduce anxiety and depression inducing an environment of more self-control.
So everyone experiences stress, but it’s how we deal with it that’s important. It is possible for us to control how much we allow into our body’s and how it affects our nervous system and hormones. This is all achieved by stimulating our parasympathetic nervous system.
To quote the great BKS Iyenga;
‘Yoga is eternal it is evergreen and timeless. It is the answer to the infinite stresses modern-day life brings us. Yoga brings balance to our lives, calms the restless mind and brings us to a point of complete quiet. It is then that we discover our true selves.’ 
American Psychological Association, undated; Stress Effects on the Body, retrieved 29/12/16; http://www.apa.org/helpcenter/stress-body.aspx
Benson, Herbert M.D. 2001; The Relaxation Response, Quill
Blum, Susan M.D., M.P.H, 2013; The Immune System Recovery Plan, Scribner Simon & Schuster, Inc
Carr,Leslie., 2 May 2013; Relaxation brings Healthy Genetic Changes, retrieved 30/12/16; http://www.thedoctorwillseeyounow.com/content/stress/art4022.html
Darou, Shawna Darou, Dr 6/1/17; How to Control Inflammation with your Brain, retrieved 6/1/17 http://upliftconnect.com/control-inflammation/
Devaney, Jacob. 31/12/16; How to Release the Stress stored in our Bodies, retrieved 3/1/16
Iyenga, B.K.S. 2014; The Path To Holistic Health, DK Publishing
Mayo Clinic Staff, 28/4/16; Stress Management, retrieved 27/12/16; http://www.mayoclinic.org/healthy-lifestyle/stress-management/in-depth/stress-symptoms/art-20050987
Stöppler, Melissa Conrad, MD, 3/6/16; Definition of Stress, retrieved 27/12/16; http://www.medicinenet.com/script/main/art.asp?articlekey=20104
Taljaard, Tanja. 2/1/17; Triggering the Relaxation Response, retrieved 4/1/2017 http://upliftconnect.com/relaxation-response/
McClure, Laura. 7/4/16; 7 Ted-Ed Lessons for a Healthier You, retrieved 5/1/16 http://blog.ed.ted.com/2016/04/07/7-ted-ed-lessons-for-a-healthier-you/
Wikipedia, undated, retrieved 27/12/16;
Wikipedia, undated, retrieved 27/12/16; https://en.wikipedia.org/wiki/Stress_(biology)#General_adaptation_syndrome
 Wikipedia – general adaptation syndrome
 Mayo Clinic Staff
 Devaney, Jacob
 Taljaard, Tanja
 Iyenga, B.K.S.