L25

• What is the most extreme environment for humans?

  Space
• What makes an environment extreme?

  Multiple stressors present or absent that challenge human survival
• Which could kill you faster, core cooling or heating?

  Core heating
• Can humans adapt to extreme environments?

  Yes, to varying extents and through different mechanisms
• What are the key factors regarding adaptation to environments?

  To which environments, to what extent, and how
• How does exercise interact with the environment acutely?

  Exercise acts as a stressor that interacts with external environmental factors
• Can fitness improve resilience in extreme environments?

  Yes, strength, power, or endurance can enhance resilience
• Can extreme environments improve fitness?

  Yes, exposure to extreme conditions can enhance physical fitness
• What does the interaction between exercise and extreme environments mean for fitness conditioning?


  It suggests that conditioning should consider environmental stressors
• What are the objectives of studying exercise and extreme environments?


  1. Understand the interaction between exercise and the environment
  2. Recognize the value of fitness in extreme environments
  3. Identify what makes an environment extreme
  4. Understand the capacity to adapt to environmental stressors
  5. Gain knowledge from extreme environments about normal function and disease

  
• What are internal and external stressors in the context of exercise and the environment?


  Internal stressors are generated by the body, while external stressors come from the environment
• Why is exercise considered a powerful stressor?


  Because it uniquely challenges the body's systems and promotes adaptation
• What is the definition of fitness in the context of extreme environments?


  Fitness is the combination of homeostatic power and capacity, leading to resilience
• How does heat stress affect fitness and health?

  Heat stress can improve several markers of fitness and health
• Which thermal stress would kill most quickly?

  Heat
• What is the most extreme environment for humanity?


  Space
• Why is the built environment considered chronically extreme?

  It is almost devoid of natural stressors, leading to decay in structures and functions
• What is the impact of insufficient physical activity in the built environment?

  It is a leading cause of morbidity and early mortality
• How do humans contribute to extreme environments?

  By becoming less able to tolerate them while potentiating their effects
• What is the nature of most environments regarding stressors?

  They are dynamic arrays of stressors
• What factors should be considered regarding the nature of exercise/activity in extreme environments?

  Physical demands, cognitive demands, and equipment reliability
• Why is it important to consider participants in extreme environments?

  Because individual differences affect performance and tolerance
• How can counter-strategies aid performance in adverse environments?

  They can help manage physiological responses to stressors
• What is the environmental stress humans can most adapt to?

  Gravity
• What is the environmental stress humans can least adapt to?

  Cold
• How do humans adapt to heat stress?

  Through various physiological changes across multiple systems
• What is the limit of human tolerance to hypoxia?

  At the summit of Mt. Everest
• How do humans respond to sustained cold stress?

  They rely on behavior and technology rather than adaptation
• What are the benefits of studying extreme environments?

  • Enhance performance in normal environments
  • Understand normal physiology and pathophysiology
  • Study mechanisms of normal function and disease
  • Investigate emergency care medicine

  
• What is the significance of environmental stress on human performance?

  It strongly influences how people feel and perform
• How can an environment that is fatal for one person be benign for another?

  Due to individual differences in tolerance and adaptation
• What artificial strategies may be needed for survival in extreme environments?

  Strategies to cope with cold, high altitude, and space flight
• What is the role of extreme environments in understanding human physiology?

  They provide insights into normal function and disease mechanisms
• What causes sleep apnea?

  caused by airways blockage (obstructive) or improper brain signals (central), affecting breathing during sleep.
• How does sleep apnea affect brain health?

  reduces brain oxygen levels, leading to cognitive issues, memory problems, stroke risk, and difficulty concentrating.
• In severe hypoxia, does the lung shunt blood to protect against capillary damage or fluid accumulation? 


  the lungs divert blood flow to cope with low oxygen, but prolonged hypoxia can cause confusion, unconsciousness, or permanent damage.