The physiology of stress

• Stress is a natural response to challenging situations that can have both physical and psychological effects on the body
• General Adaptation Syndrome (GAS)

  1. Alarm stage

  2. Resistance stage

  3. Exhaustion stage
• Alarm stage


  The body perceives a stressor and initiates the fight-or-flight response
• HPA axis


  Involves the release of hormones from the hypothalamus, pituitary gland, and adrenal glands, particularly cortisol
• Sympathomedullary pathway


  Triggers the release of adrenaline and noradrenaline from the adrenal medulla
• Effects of cortisol


  • Helps regulate metabolism
  • Controls inflammation
  • Maintains blood pressure
  • Suppresses non-essential functions
• Resistance stage


  The body tries to adapt to the ongoing challenge
• Exhaustion stage


  The body's resources become depleted, leading to physical and mental exhaustion
• Prolonged exposure to high levels of cortisol can have detrimental effects on various bodily systems
• Bodily systems affected by high cortisol

  • Immune system
  • Cardiovascular system
  • Cognitive function
• Understanding the physiology of stress is crucial as chronic stress can have serious implications for health and well-being
• It is essential to develop effective strategies to manage stress and build resilience to cope with life's challenges
• Role of HPA axis, sympathomedullary pathway, and cortisol


  In the body's response to stress
• Individuals can take proactive steps to mitigate the negative impact of stress on their overall health