PHYSICAL & ENVIRONMENTAL STRESSORS
What are two major environmental stressors affecting military personnel in field conditions, and how do they impact performance?
Extreme temperature (heat/cold) and physical workload (load carriage). They reduce endurance, increase fatigue, and impair cognitive performance.
What is thermal load?
The total heat stress on the body from environmental temperature, metabolic heat, and clothing insulation.
Why is hydration critical for soldiers?
It maintains blood volume, thermoregulation, and physical and cognitive performance.
Name one common route of infection in military field conditions.
Fecal-oral transmission through contaminated water or food.
Name two effects of sleep deprivation.
Reduced attention and impaired decision-making.
How does prolonged physical exertion with heavy load affect the cardiovascular system?
It increases heart rate and oxygen demand, leading to cardiovascular strain, reduced efficiency, and earlier onset of fatigue.
How does humidity affect thermoregulation?
High humidity reduces evaporation of sweat, impairing heat loss and increasing risk of overheating
What are the effects of dehydration on performance?
Reduced endurance, impaired concentration, increased fatigue, and higher risk of heat injury.
How does poor sanitation lead to outbreaks?
It allows pathogens to spread via contaminated environment, water, and food.
How does chronic stress affect cognition?
It impairs memory, slows reaction time, and reduces judgment accuracy.
What happens physiologically at high altitude and how does it affect soldiers?
Reduced oxygen pressure causes hypoxia, increased respiration, and decreased aerobic capacity, leading to reduced physical and mental performance.
Differentiate heat exhaustion and heat stroke.
Heat exhaustion involves dehydration and fatigue; heat stroke involves failure of thermoregulation and is life-threatening with CNS dysfunction.
What happens metabolically during prolonged calorie deficiency?
The body uses fat and muscle for energy, leading to weight loss, weakness, and reduced immunity.
Why are vector-borne diseases common in deployment zones?
Presence of stagnant water, warm climates, and exposure to insect vectors like mosquitoes.
What is the relationship between fatigue and operational errors?
Fatigue increases cognitive lapses, leading to higher probability of mistakes and accidents.
Why is combined heat exposure and physical workload dangerous?
It overwhelms thermoregulation, leading to dehydration, heat exhaustion, or heat stroke due to failure of heat dissipation mechanisms.
How does protective clothing affect heat balance?
it traps heat, reduces sweat evaporation, and increases internal body temperature.
Why is electrolyte balance important during exertion?
It maintains nerve conduction, muscle function, and prevents cramps or cardiac irregularities.
What is the primary intervention in a diarrheal outbreak in a camp?
Immediate water sanitation, isolation of cases, and hygiene enforcement.
How does psychological stress affect physical health?
It increases cortisol levels, suppresses immunity, and contributes to cardiovascular strain.
How do environmental stressors collectively affect operational efficiency?
They interact synergistically, increasing fatigue, error rates, injury risk, and reducing decision-making ability under sustained operations.
What principles should guide work-rest cycles in hot environments?
Balance heat production and dissipation by limiting continuous exposure, ensuring hydration, and adjusting workload based on environmental conditions.
What factors must be considered in designing military rations?
Energy expenditure, climate, micronutrient needs, hydration requirements, and ease of transport/storage.
Why are hygiene interventions more effective than antibiotics alone?
Because they prevent transmission at the source, while antibiotics only treat existing cases and do not stop spread.
What are key components of a fatigue management strategy?
Sleep scheduling, workload rotation, nutrition, hydration, and psychological support systems.