The HPA-Axis  Your Threat Response System

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Define and explain the HPA-Axis
Identify the impact of chronic stress/cumulative trauma on the HPA-Axis
Identify symptoms of HPA-Axis dysfunction
Identify interventions useful to help regulate/restore the HPA Axis
What is the HPA Axis
Hypothalamic-Pituitary-Adrenal Axis AKA the Threat Response System
Controls reactions to stress and regulates many body processes, including digestion, the immune system, mood and emotions, sexuality, and energy storage and expenditure
The ultimate result of the HPA axis activation is to increase levels of cortisol in the blood during times of stress.
Cortisol's main role is in releasing glucose into the bloodstream in order to facilitate the “flight or fight” response. It also suppresses and modulates the immune system, digestive system and reproductive system.
HPA Axis in Brief
Stressor HPA-Axis Activation
What is a stressor?
Lack of sleep
Lack of adequate nourishment
Unsafe environment
Rejection, Isolation, Failure, Loss of Control, The unknown
Stress/Poor Time Management

HPA-Axis Activation Cortisol
Breaks down dopamine (pleasure chemical) to make Norepinepherine
Releases Glutamate
Sex hormones (estrogen and testosterone)
Reduces serotonin availability (depression/anxiety)
Impairs sleep (primary stressor)
Alters appetite
Impairs hormonal balancing

What are your stressors
Medication (stimulants, opiates)
Low self-esteem/Fear of Abandonment
Time management: Burning the candle at both ends/overcommitted
What can you do to start addressing them?

Long Term Consequences
Dysfunctional HPA axis activation will result in
Abnormal immune system activation
Increased inflammation and allergic reactions
IBS symptoms such as constipation and diarrhea,
Reduced tolerance to physical and mental stresses (including pain)
Altered levels of sex hormones (think menopause)
Weight gain (especially in the abdomen)
Impaired sleep

A variety of stressors activate your Threat Response System
Several “consequences” of the threat response system activation … activate the threat response system  downward/negative spiral
Extended activation leads to exhaustion, depression and burnout
While many stressors may take some time to address, it is vital to eliminate and minimize any other stressors.
Think of it as a rolling brown out.
Anything that reduces stress will likely improve sleep and the functioning of the HPA-Axis.
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HPA-Axis Dysfunction
The body reduces its HPA axis activation when it appears that further fight/flight may not be beneficial. (Hypocortisolism)
Hypocortisolism seen in stress-related disorders such as CFS, burnout and PTSD is actually a protective mechanism designed to conserve energy during threats that are beyond the organism's ability to cope.
Fatigue is actually an emotion generated in the brain, which prevents damage to the body when the brain perceives that further exertion could be harmful.
Fatigue in sports is largely independent of the state of the muscles themselves and is more related to:
Physical factors
Core temperature
Glycogen levels
Oxygen levels in the brain
Sleep deprivation
Levels of muscle soreness/fatigue
Fatigue cont…
Psychological factors reducing fatigue
Emotional state
Knowledge of the endpoint
Other competitors/motivation
Visual feedback
Fatigue is one sign that the body is getting ready to downregulate the HPA-Axis
How can you reduce fatigue and help restore HPA-Axis functioning?