Transcript Adapting to the Outdoor Environment

Adapting To An Outdoor
Environment
Remote Areas Emergency Medicine
and Survival
Objectives
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Identify survival requirements of the human
body.
Explain how the outdoor environment effects
the major systems of the body.
Identify methods of adapting to functioning in
the outdoor environment.
Objectives
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Explain the importance of nutrition and physical
conditioning in adapting to the outdoor
environment.
Skill Performance
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Demonstrate layering principles using typical ski
clothing.
Vocabulary
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Acclimatization- the process by which the body adjusts to a
new environment.
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Alveoli- the smallest air sacs of the lungs.
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Homotherm- a human or other warm blooded animal that
maintains a constant body temperature despite changes in
environmental temperature.
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Hyperventilation- deep rapid breathing
Vocabulary
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Vapor barrier garment- a waterproof garment
worn either next to the skin or over a thin
garment of polypropylene.
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Windchill effect- the cooling effect of the wind
added to low environmental temperature.
Survival Requirements
of the Human Body
Survival Requirements
For basic survival the human body needs:
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Oxygen
Stable body temperature
Water
Food
Will to live
Physical integrity
Oxygen
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A necessary component of life
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Is supplied to the body through the lungs and alveoli
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A constant supply of oxygen is needed by the body
Oxygen
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The body can be deprived of oxygen by injury or
moving to high altitude
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At high altitude the body can adjust through
acclimatization.
Acclimatization
Acclimatization occurs...
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Hyperventilation
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Improvement in the blood’s oxygen intake and oxygencarrying capacity
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Heart and skeletal muscle action become more efficient
Acclimatization
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To encourage acclimatization allow enough time for
a slow ascent to altitude.
Provide a rest day after ascent to 10,000 feet above
sea level.
Oxygen
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The body also can be deprived of oxygen by injury.
Temperature
The mechanisms of the body work best when it is…
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Well fed
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Hydrated
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Properly rested
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In good condition
Temperature
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If these mechanism fail to maintain body heat in an
optimal range, injury can occur due to cold such as
frostbite or due to heat such as heat stroke.
Environmental Effects
on Major Body
Systems
Heat Loss
The human body is composed of …
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Core (nervous system, heart, lungs, internal organs)
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Shell (muscles, skin and extremities)
Heat Loss
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When the body attempts to adjust body temperature it
may do so for the core at the expense of the shell
temperature.
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We must understand how temperature is lost and how
to prevent the loss.
Heat Loss
Heat is lost or gained from the human body in five ways:
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Conduction
Convection
Evaporation
Radiation
Respiration
Conduction
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The direct loss of heat by contact
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The amount transferred depends on the temperature
difference and material involved
Convection
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The transfer of heat when air of a different
temperature moves across the body surface
Evaporation
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Occurs when water or other liquids on the body’s
surface are converted to vapor
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Can be a beneficial loss in hot climates
Radiation
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Is the transfer of heat to or form the body through
infrared waves
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Heat loss from uncovered skin is through radiation
Respiration
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The heat lost as cool air is inhaled and warmed by the
body before being exhaled
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Heat also can be gained in this way during hot weather
Heat Loss
A body at rest at 21° C and average humidity loses
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70% through radiation, conduction and convection.
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27 % through evaporation
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3% through body functions
Heat Loss
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The body has voluntary and involuntary methods of
both increasing and decreasing heat loss.
Methods of Decreasing Body
Heat Loss
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Involuntary
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Decrease perspiration
Shunt blood away from
the shell
Decrease body surface
area (curl into ball)
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Voluntary
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Add clothing
Seek shelter from
chilling mechanism
Stay dry; get out of wet
clothing
Heat Loss
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The body has three
methods for avoiding
dangerous degrees of
cooling:
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Increase internal heat
production
Add heat from
environment
Decrease heat loss
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The most energy
efficient is to avoid the
heat loss.
Methods of Increasing
Body Heat Loss
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Involuntary
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Increase perspiration
Shunt blood to the shell
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Voluntary
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Subtract clothing
Seek shelter from
warming mechanism
Expose more skin
Cool with water
Practical Ways of Decreasing
Body Heat Loss
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Avoid alcohol and nicotine
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Avoid getting wet
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Use personal floatation device
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Avoid contact with cold surfaces
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Protect from windchill effect
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Avoid excessive respiratory heat loss
Practical Ways of Decreasing
Body Heat Loss
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Use optimal insulation materials for clothing such as:
wool, polypropylene, down, polyester pile, etc.
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Avoid cotton in cold wet weather
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Use layering so that clothing can be added or
subtracted as needed
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Adequately cover body parts such as head, ears, finger,
feet
Adapting to the
Weather
Adapting
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There are many things that we can do to help the body
adapt to the outdoor environment.
Cold Weather Clothing
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Proper layering and the use of insulated clothing can
protect the body from cold
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Use a four layer system of clothing
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Select based on the environment and expected weather
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Choose materials with insulating values
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Layer one
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Underwear-wool,
thermax, polypropylene
and blends; avoid
cotton
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Socks-wool or
polypropylene, use one
thin pair near skin with
thick outer sock
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Layer Two
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Shirt-wool or
polypropylene
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Pants-same material as
shirt; avoid cotton
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Boots-activity
dependent
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Third Layer
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Parka-down or fiberfill,
wind and water proof
Wind pants-water and
wind proof
Hat-wool or poly
Mitten or Gloves- glove
liners
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Fourth Layer
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Extra layer such as
quilted vest in pack
Other considerations
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Rain gear
Vapor barrier
Cold Weather Survival Kit
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Shelter Building
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Plastic tarp
Shovel
Nylon cord
Folding saw, ax
Signaling
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Whistle
Mirror
Flashlight
change for phone
Signal cards
Fire Building
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Waterproof matches
Firestarter
Candle
Knife
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Optional
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Therm-A-Rest
Stove and fuel
Sleeping bag
Cold Weather Survival Kit
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Other
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Compass
Map
Metal pot and cup
Emergency care kit
Toilet paper
Sunglasses
Sunblock cream
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Lip salve
Spare socks
Spare mittens
Canteen (full)
Food
Extra layer of clothing
Avalanche poles
Adapting to Hot Weather
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Heat stress is related to both temperature and
humidity.
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Serious heat stress can occur if the core temperature
rises above 40° C for a significant period of time.
Adapting to Hot Weather
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The body adapts in the following ways:
 Blood volume increases
 Heart efficiency improves
 Perspiration starts sooner and increases in volume
 Perspiration contains less salt
Adapting to Hot Weather
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Increasing Body Heat
Loss
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Expose as much skin as
possible
Wear light loose cotton
clothing
Drink plenty of fluids
Acclimatize
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Reducing Heat Gain
from the Environment
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Wear protective clothing
Seek shade
Avoid hot objects
Do not lie on ground
Decrease muscular
activity
Nutrition and
Conditioning
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Lack of proper nutrition can cause weight loss,
depression, apathy, and lack of coordination
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Poor nutrition and fitness can cause fatigue,
lack of endurance, lack of tolerance to heat and
cold, etc.
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The six groups of nutrients are:
 Carbohydrates
 Fats
 Proteins
 Vitamins
 Minerals
 Water
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Carbohydrates include fruits, vegetables, sugar and
cereals.
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Protein sources include eggs, dairy products, meat, fish,
poultry, nuts and peas.
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Fat sources include butter, dairy products, meat eggs,
nuts, butter, lard, cooking oil, chocolate, mayonnaise,
fried foods, and ice cream.
Nutrition
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Water makes up 60% of the body.
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A sedentary person must replace 2.5 liters per day.
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More is needed at altitude, hot weather, or during
exertion ( 3 to 4 liters).
Physical Fitness
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Important to members of outdoor recreation or rescue
groups because their activities can impose unusual
physical demands
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Important to develop and maintain a high level of physical
fitness
Fitness Program
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Warm-up
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Calisthenics or sports to develop motor fitness
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Endurance training to develop cardiovascular fitness
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Cool down period
Fitness
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The goal and end result of any endurance sport should
be to maximize the body’s ability to take up and use
oxygen.
Fitness
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A good fitness program should aim for a minimum
workout of 45 minutes at least 4 times a week.