Responding to stress

Adaptive physiology

Responding to Stress

The link between mind and body is one of the basic tenets of the newly developing science of psychoneuroimmunology, which has been part of chiropractic concepts since the profession was founded. Chiropractors have maintained the body possesses well-designed “survival mechanisms” intended to maintain a state of good health.

The human body responds to the world around us physically, mentally and emotionally. Notice what happens when you get a fright: your body tightens, (mostly around your spine) your pupils dilate, your heart rate and blood pressure rise and adrenaline rushes into your blood stream. At the same time your brain functions change and blood flow shifts away from your digestive and reproductive systems into your heart, lungs and muscles. This response (known as flight or fight response) is just one example of your body’s many defensive stress responses that are grouped under the umbrella term ‘adaptive stress response.

The flight or fight response and other adaptive stress responses are generated by the primitive or reptilian part of your brain (responsible for the unconscious going on of your body, breathing, digestion etc.) and they protect you from injury, help you cope with stress and survive. An important aspect of these stress responses is that they help us cope with the emotional or mental content associated with some stressors.

During times of stress it can be useful (from a survival point of view, which is one of the responsibilities of this part of your brain) to think rationally and react quickly, rather than thinking abstractly, feeling or expressing emotionally. As a result we’ve developed the capacity to compartmentalise out thoughts in the face of mental stress and the ability to ‘bottle up’ our feelings storing them for later.

These are Constructive mechanisms, defensive or adaptive stress responses are very healthy to have when physical, mental or emotional stresses are occurring, and they happen even under seemingly minor stress. Normally these tensions and responses ease soon after when the stresses do, with your brain and body relaxing back to its normal state.

However, our brains, made up of nerve cells, are different to other tissues in the body, in that they have a characteristic called ‘plasticity’. They are able to adapt and learn and change their function. There are also able to come ‘stuck’, in the sense that means remaining ‘ on ‘ in the stress response hours, days or even years after the stress has passed. The technical way of describing this is a retained adaptive stress response.

The most extreme example of RASR is known as Post Traumatic Stress Disorder (PTSD) in response to an excessive stress a person’s brain becomes ‘stuck’ in responding to that stress for years after it has passed leading to tensions, discomfort, change in personality, reduced motivation, decreased ability to relate and adapt to further stresses.

PTSD is an extreme version remaining ‘stuck’ in a state of stress response can also occur with mild to moderate stresses. Long term stress can shut down systems or functions that promote long-term maintenance of our well-being (digestion, immune system, function etc.)
These responses, collectively called adaptive stress responses, are designed to be short lived and when this is the case they are extremely healthy and cause few problems. However, when the balance of our function is shifted toward “stress physiology” in the mid to long term any one of these systems can become more vulnerable to exhaustion or breakdown.

For example: A person under chronic stress can have affects on the Cardiovascular System which leads to Increased heart rate and blood pressure placing a greater load on the cardiovascular system. The blood vessels supplying muscles dilate to allow a greater delivery of energy, while the vessels in other areas such as around our digestive tract constrict.

The digestive System, due to this suppression hinders our ability to absorb nutrients. Intestinal function and movement of contents along the digestive tract may either slow considerably or become hyperactive depending on the individual and level of stress experienced. If transit time is reduced foods in the process of intestinal digestion may remain in parts of the digestive tract for longer than ideal – a postulated theory behind irritable bowel syndrome and food intolerance. Over time this progressive build up can have a dramatic effect on your health and well-being on every level – physically, mentally and emotionally.

Stress affects all of us differently due to our differing constitutions and genetic heritage, and the way we experience them over time. Normally the build-up occurs slowly to the degree that its simply accepted as “normal” or “how we are”, tighter, less flexible, with a certain level of energy etc.. As the tensions or other effects of the retained stress responses accumulate, our “reserve capacity” diminishes and with many of us it’s our body breaking down, becoming painful, or other symptoms developing that are the first things we notice. Because our conscious mind operates largely from a separate region we can be mentally coping with stress well and are often surprised to find our body telling a different story; aches and pains, skin conditions, digestive troubles, frequent colds, cardiovascular issues.

Stress and its effects

The reason stress has such a wide-ranging impact on our health and well-being is that our stress responses are generalized or global responses. This means that everybody system, as well as our mental states and behaviour are affected in some way when we experience stress. Appetite is also affected; often this will increase with short term stress but is more often suppressed in the case of long term stress.

Muscular- skeletal system

Perhaps the most noticeable change for most people is that the muscles of the body become tighter in order to be ready for action. This places a higher load on and all the other tissues associated with movement and stability (ligaments, tendons, discs etc.)

Immune system

An extensive body of research shows that immune system function is compromised by stress. Some specific findings suggest that stress directly stimulates inflammation in the body, healing is slowed and the protective function of the immune system declines.

Reproductive system

Both male and female reproductive systems can be greatly suppressed

Sensory Systems

Increased priority and sensitivity of our extended senses- this heightened awareness makes it easier in the short term to focus on incoming information related to any form of threat, but over time it can lead to being easily distracted and difficulty concentrating.

Hormonal System

Areas of the brain, as well as the adrenal glands play a central role in our adaptive stress response. They contribute to all of the changes in function talked about above, and also leads to increases in circulating blood sugar and altered metabolism of fat stores.