Stress, Wellbeing and Performance part 1 of 3

TotalMSK Blog: Stress, the Individual, Wellbeing, Performance (1/3) - An MSK Therapy perspective.

Stress, the Individual, Wellbeing, Performance & the Workplace Part 1

Historically, there has always been a view that there is a link between physical and mental well-being and vice versa. A great deal of research has been carried out into the relationships between various aspects of health including physical and psychological well-being over the years. There is an ever-increasing evidence base from multiple areas of research suggesting that physical and mental well-being are inextricably linked. However, there are numerous factors affecting health, and one could argue that there are multiple types of health or wellness. One can broadly categorise these inter-related areas of health as:-

Holistic Health Model (Physical, Emotional, Mental, Environmental, Social, Spiritual)

Holistic view of Health and Wellbeing a Model

All of these types of health and well-being are interrelated, and the relationships are far from being fully understood.  "Stressors" can take many forms and affect every kind of health and thus overall health. Research has demonstrated significant links between various aspects of health. Hence, a pure BioPsychoSocial model of health is a little too simplified. The human stress response also has implications for developing chronic pain and treating consumers with chronically painful conditions. See the article on Chronic Pain for further details on aspects of such conditions and treatment.

stress response elite military David Stirling (SAS)

Elite Sports and Elite Military units have always appreciated the relationships between physical health, psychological welfare, and superior performance. Such organisations have invested considerable amounts of time, finance, research, and effort to ensure that they recruit, select, train and retain the very best candidates. In the case of the worlds elite military services, this includes individuals who are the best physically and psychologically suited to the demands of such a career. Diversity also plays a considerable part in the effectiveness of such Elite teams, with the selection of individuals coming from all walks of life, provided that they meet high and exacting physiological and psychological standards set by the selection course(s).  Industry can learn a great deal from these elite level individuals and top performing teams. Such, organisations and cultures continually strive to push the limits of human and performance daily, or as one now infamous British Military Unit would say, 'the unrelenting pursuit of excellence.' Even slight enhancements in performance can prove critical regarding winning and losing, or actual life and death. It is also of paramount importance that organisations get a good return on their investment. Such organisations fully understand the value of their people and the level of investment in said people. Hence, utilisation and career longevity from these elite level personnel is paramount and not merely from a return on investment perspective.  Not only does physical and mental wellbeing have a direct impact on performance, but it is relatively easy to see the links between physical and psychological wellbeing.

As remarkable and as versatile as the human body is, the body does make various trade-offs. The human body has some extremely sophisticated systems, and yet these do not all need to be running concurrently and all of the time. Indeed, each system or process will utilise various resources and the human body only has finite resources and operates on an efficiency basis. Historically, multiple food sources would have been in short supply, and yet each bodily function consumes energy, various nutrients, and water. Examples of efficiency tradeoffs include the way the brain operates, how we make decisions, how tissues within the body repair and how we deal with stress. Hence, the human body manages resources to be as efficient as possible, by moderating the level that various systems operate at and by turning systems on and off accordingly.

A primeval Survival Mechanism - Fight, Flight or (Freeze) Response

Human Stress Response fightHuman Stress Response flightHuman Stress Response freeze

Pretty much any form of stress creates a similar initial physiological response within the body and initiates the "fight, flight or (freeze)" response. This response is virtually instantaneous regardless of the stressor, and the body takes the view that there is an imminent threat to life. Fortunately, it is fairly uncommon for the vast majority of the population to experience a real threat to life in today’s society. However, "perception" plays a huge part in what one might deem to be a threat or “stressor.". A “stressor” can take many forms of threat, be it physical, biological, psychological, social, personal values related, financial, environmental, political beliefs, religious beliefs or any multitude of form factors. The human Central Nervous system (CNS) is made up of various parts, divisions, and sub-divisions. In simplistic, terms the “fight, flight or (freeze)” response aims to give a person or animal the best chances of survival in any, given perceived life-threatening situation. In essence, the body becomes turbocharged in preparation to “fight” or “flight” (run away), from a life-threatening situation. The “freeze” response is slightly different and is thought to occur due to the perceived life-threatening situation overwhelming a person or animals abilities or capacities to cope with the given situation. In some situations, people or animals will not "fight" or "flight" (run away),  and will just “freeze,” much like a deer in the headlights. In some, perceived life-threatening situations the “freeze” response might work, but not in others could prove fatal. The physiological processes that enable/control the “fight, flight or (freeze)” response are related to the CNS.  Physiologically, there are two particularly important parts of the Central Nervous System (CNS) involved in dealing with threats and repairing the body. These parts of the nervous system are part of the Autonomic Nervous System (ANS) and are called the Sympathetic and Parasympathetic Nervous Systems.

Sympathetic Nervous System (SNS)

stress, homeostasis threat assessment

The Sympathetic Nervous System (SNS) is responsible for multiple life-sustaining functions, including aspects of threat assessment and the fight, flight, freeze response. The SNS is continuously working at a base level maintaining homeostasis, even when the Parasympathetic Nervous System (PSNS) is operating. Sensory inputs and information are continually sent to the brain for processing via the CNS. The control of essential life support functions and homeostasis happens at a subconscious level. We do not even have to think about making our heartbeat, breathing, or the maintenance of other vital life-giving actions, such as blood PH values, blood glucose levels or temperature regulation. Such critical aspects of self-maintenance have a "normal or safe" operational level, and relatively small deviations from these normal "safe" levels can prove fatal. Hence, all of these functions are taken care of subconsciously, and the vast majority of these functions cannot be directly controlled consciously by us.  There are various sensors within the body, which are constantly being monitored, with the body making any necessary adjustments on the fly to maintain homeostasis. There are also sensory inputs that we are far more familiar with or at least know are working. We are all familiar with the five basic senses of; touch, sight, smell, hearing, and taste. If any of these primary senses detect anything that the brain perceives as a threat, then the Sympathetic Nervous System instantaneously activates.  The activation of the Sympathetic Nervous System is a highly efficient and effective ancient survival mechanism, commonly referred to as the “fight, flight or (freeze)” response.  The stress response involves the sending of sensory information to the amygdala from any one or number of the "primary" sensors. The amygdala is a small part of the brain, located near the brainstem and which is involved in the processing of emotions. If the amygdala interprets '"perceives" inputs from the primary sensors as a threat, then a distress/alarm signal is instantly sent to another part of the brain the hypothalamus. One can view the hypothalamus as a control centre, based on the far-reaching effects it can have on the body. There are two parts to the “fight, flight or freeze” response. Firstly, the hypothalamus activates the initial “fight, flight or freeze” response, via the autonomic nervous system. The hypothalamus instructs the adrenal glands to release both adrenaline and norepinephrine into the bloodstream.

stress hormones release

The hormonal release produces a large number of changes throughout the body, including shutting down the Parasympathetic Nervous System function. If one has a choice of "fight" or run away from a threat, then all resources need to be aimed at those activities and not digesting food, resting or procreating. The initial release of adrenaline and norepinephrine into bloodstream creates multiple changes within the body including, increasing heart rate, respiration, blood pressure, muscle tension and releasing stored nutrients and energy from tissues within the body. The increase in oxygen and nutrients within the blood supply to the brain heightens all five of the primary senses. The increase in muscle tension helps to protect the body from potential physical harm and also reduces blood flow to the superficial tissues (skin). The tensioning or armouring of the bodies tissues also impacts tensional and compressive forces throughout the body (Biotensegrity) see article. Reducing blood flow to the superficial tissues would minimize blood loss should the person or animal get injured while dealing with imminent danger. The increase in oxygen, nutrients and energy supplies within the blood also primes the musculoskeletal system, to "fight" or "flight" (run away) from danger. The "fight, flight or (freeze)" response is so efficient that the human body has already reacted subconsciously before us consciously registering a threat. Which, explains why people can often get out of the way of danger before getting injured. Prolonged exposure to stressors not only affects biotensegrity, but the tissues within the body can adapt (see adaptation article) to these changes in forces.

The second part of the “fight, flight or (freeze)” response is relatively instantaneous, but slightly slower than the initial reaction and enhances the primary response and keeps the body in a high state of readiness. The hypothalamic-pituitary-adrenal axis is responsible for the release and control of levels of cortisol in the bloodstream, via a negative feedback loop. The hypothalamus releases corticotropin-releasing hormone (CRH), which makes the pituitary gland release adrenocorticotropic hormone (ACTH). The presence of ACTH is detected by the adrenal glands and these glands then release cortisol into the bloodstream.

stress physical response

Historically there would have most likely been some form of physical activity straight after or shortly after the “fight, flight or (freeze)” process had been initiated, hopefully resulting in personal survival. Once a perceived threat to life has passed, then sensory inputs to the brain allow the brain to return the Sympathetic Nervous System to running at a base level. Blood cortisol levels would then be able to reduce via the negative feedback loop. However,  the inhibition of this process during the “fight, flight or (freeze)” response, prevents cortisol levels from normalising. Under normal circumstances, the detection of high levels of cortisol in the bloodstream blocks the release of CRH and thus the release of ACTH. Which, in turn, results in a decrease in cortisol within the bloodstream. Importantly, the removal of the perception of a “stressor” stops the inhibition of the Parasympathetic Nervous System from functioning normally.

Parasympathetic Nervous System (PSNS) - Rest and Digest / Feed and Breed

rest and digest, feed and breed (stress)

The Parasympathetic Nervous System plays a crucial role in calming the body after a perceived threat has passed. The PSNS is responsible for functions involving “rest and digest” and or “feed and breed” and is also part of the Autonomic Nervous System (ANS). The PSNS is responsible for controlling many bodily functions, which are essential to physical and mental health and the continuation of the human species. Besides slowing the heart rate and blood pressure after the initiation of the “fight, flight or (freeze)” response, the PSNS also plays a major role in the regulation of other functions. Other functions include the regulation of digestion, urination, defecation, sexual arousal, menstruation, memory formation and the repair of tissues and structures throughout the body. The metabolic processes that the PSNS controls can only be regulated, if the PSNS can function and is not inhibited by the SNS during a “fight, flight or (freeze)” response.

Ancient Survival Mechanism in a Modern World

primeval stress response modern day

Historically, the ancient “fight, flight or (freeze)” response would have initiated due to an imminent threat to life. One would then have had to "fight" or "flight" (run away), to survive. Provided that one survived and the threat to life had passed, the SNS would start to return to running at base level again. Either way, the stress response usually required an element of physical activity after being initiated. The time it can take for SNS to return to running at base level after starting the stress response can vary a great deal and take anything from 30 minutes to a couple of days. Such variations are thought to be down to many factors including, but not limited too, genetics, health/fitness, diet, training and previous experiences. Hence, historically the chances of the SNS consistently activating would have been slim at best. Hence, the functions of the PSNS would have been able to operate regularly. However, the modern world we live in today is hugely different from that of our ancestors. Today’s modern world has very different stressors, which are rarely life-threatening and yet the bodies primaeval response to stress is the same. Furthermore, the stress response can be initiated multiple times a day and even for extended periods. If the stress response is continually activated then the PSNS is continuously prevented from regulating critical metabolic processes.

"Stress, the Individual, Wellbeing, Performance and the Workplace (Part Two)", will look in more detail at the possible effects of long-term Stress and various interventions, which relate to Corporate Wellness, the individual and human health in general.

The article was written by Terry Davis MChiro, BSc (Hons), Adv. Dip. Rem. Massag., Cert. WHS.

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About the Author

As of December 31st 2020, the author chose to leave the Chiropractic profession, due to a planned move back to Australia and where is training and education are not recognised. He no longer works as a Chiropractor and works as a Myotherapist in Morningside, Brisbane. The author possesses an unusual background for somebody who trained in the McTimoney Chiropractic technique. His education, training, and practical experience span over two decades and relate to both health's physical and mental aspects. He has also needed to push his own body and mind to the limits of physical and psychological endurance as part of his time serving in Britain's elite military forces. His education includes a bachelor of science degree in Business Management, with a specialisation in psychology and mental health in the workplace, an Integrated Masters in Chiropractic, MChiro and a multitude of soft-tissue therapy qualifications (see the about section for more details). His soft tissue qualifications range from certificate level right through to a BTEC Level 5 Advanced Diploma in Clinical Sports and Remedial Massage Therapy. Terry also has extensive experience in security, work, health and safety and holds relevant certifications. He has also taught as a senior course coach at Advanced Diploma level (Myotherapy / Musculoskeletal Therapy) in Australia, both theoretical and practical aspects including advanced Myofascial Release Techniques and has certification in training and assessment. Terry will have taught many of the first students to train as Myotherapists in Brisbane. Terry's combination of knowledge through education, training, elite military service, and personal injury history has paid dividends for the consumers he sees and has treated over the last 15 years. He has extensive experience treating chronic pain and work and sports-related musculoskeletal injuries. Terry is still very active and enjoys distance running, kayaking, mountain biking and endurance-type activities.