Adapting To An Outdoor Environment

1. Adapting To An Outdoor Environment Remote Areas Emergency Medicine and Survival

2. Objectives 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.

3. Objectives • Explain the importance of nutrition and physical conditioning in adapting to the outdoor environment. • Skill Performance • Demonstrate layering principles using typical ski clothing.

4. Vocabulary Acclimatization- the process by which the body adjusts to a new environment. Alveoli- the smallest air sacs of the lungs. Homotherm- a human or other warm blooded animal that maintains a constant body temperature despite changes in environmental temperature. Hyperventilation- deep rapid breathing

5. Vocabulary Vapor barrier garment- a waterproof garment worn either next to the skin or over a thin garment of polypropylene. Windchill effect- the cooling effect of the wind added to low environmental temperature.

6. Survival Requirements of the Human Body

7. Survival Requirements For basic survival the human body needs: • Oxygen • Stable body temperature • Water • Food • Will to live • Physical integrity

8. Oxygen • A necessary component of life • Is supplied to the body through the lungs and alveoli • A constant supply of oxygen is needed by the body

9. Oxygen • The body can be deprived of oxygen by injury or moving to high altitude • At high altitude the body can adjust through acclimatization.

10. Acclimatization Acclimatization occurs... • Hyperventilation • Improvement in the blood’s oxygen intake and oxygen-carrying capacity • Heart and skeletal muscle action become more efficient

11. Acclimatization • 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.

12. Oxygen • The body also can be deprived of oxygen by injury.

13. Temperature The mechanisms of the body work best when it is… • Well fed • Hydrated • Properly rested • In good condition

14. Temperature • 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.

15. Environmental Effects on Major Body Systems

16. Heat Loss The human body is composed of … • Core (nervous system, heart, lungs, internal organs) • Shell (muscles, skin and extremities)

17. Heat Loss • When the body attempts to adjust body temperature it may do so for the core at the expense of the shell temperature. • We must understand how temperature is lost and how to prevent the loss.

18. Heat Loss Heat is lost or gained from the human body in five ways: • Conduction • Convection • Evaporation • Radiation • Respiration

19. Conduction • The direct loss of heat by contact • The amount transferred depends on the temperature difference and material involved

20. Convection • The transfer of heat when air of a different temperature moves across the body surface

21. Evaporation • Occurs when water or other liquids on the body’s surface are converted to vapor • Can be a beneficial loss in hot climates

22. Radiation • Is the transfer of heat to or form the body through infrared waves • Heat loss from uncovered skin is through radiation

23. Respiration • The heat lost as cool air is inhaled and warmed by the body before being exhaled • Heat also can be gained in this way during hot weather

24. Heat Loss A body at rest at 21° C and average humidity loses • 70% through radiation, conduction and convection. • 27 % through evaporation • 3% through body functions

25. Heat Loss • The body has voluntary and involuntary methods of both increasing and decreasing heat loss.

26. Methods of Decreasing Body Heat Loss • Involuntary • Decrease perspiration • Shunt blood away from the shell • Decrease body surface area (curl into ball) • Voluntary • Add clothing • Seek shelter from chilling mechanism • Stay dry; get out of wet clothing

27. Heat Loss • The body has three methods for avoiding dangerous degrees of cooling: • Increase internal heat production • Add heat from environment • Decrease heat loss • The most energy efficient is to avoid the heat loss.

28. Methods of IncreasingBody Heat Loss • Involuntary • Increase perspiration • Shunt blood to the shell • Voluntary • Subtract clothing • Seek shelter from warming mechanism • Expose more skin • Cool with water

29. Practical Ways of DecreasingBody Heat Loss Avoid alcohol and nicotine Avoid getting wet Use personal floatation device Avoid contact with cold surfaces Protect from windchill effect Avoid excessive respiratory heat loss

30. Practical Ways of DecreasingBody Heat Loss Use optimal insulation materials for clothing such as: wool, polypropylene, down, polyester pile, etc. Avoid cotton in cold wet weather Use layering so that clothing can be added or subtracted as needed Adequately cover body parts such as head, ears, finger, feet

31. Adapting to the Weather

32. Adapting • There are many things that we can do to help the body adapt to the outdoor environment.

33. Cold Weather Clothing • Proper layering and the use of insulated clothing can protect the body from cold • Use a four layer system of clothing • Select based on the environment and expected weather • Choose materials with insulating values

34. Layer one • Underwear-wool, thermax, polypropylene and blends; avoid cotton • Socks-wool or polypropylene, use one thin pair near skin with thick outer sock • Layer Two • Shirt-wool or polypropylene • Pants-same material as shirt; avoid cotton • Boots-activity dependent

35. Third Layer • Parka-down or fiberfill, wind and water proof • Wind pants-water and wind proof • Hat-wool or poly • Mitten or Gloves- glove liners • Fourth Layer • Extra layer such as quilted vest in pack • Other considerations • Rain gear • Vapor barrier

36. Cold Weather Survival Kit • Shelter Building • Plastic tarp • Shovel • Nylon cord • Folding saw, ax • Fire Building • Waterproof matches • Firestarter • Candle • Knife • Signaling • Whistle • Mirror • Flashlight • change for phone • Signal cards • Optional • Therm-A-Rest • Stove and fuel • Sleeping bag

37. Cold Weather Survival Kit • Other • Compass • Map • Metal pot and cup • Emergency care kit • Toilet paper • Sunglasses • Sunblock cream • Lip salve • Spare socks • Spare mittens • Canteen (full) • Food • Extra layer of clothing • Avalanche poles

38. Adapting to Hot Weather • Heat stress is related to both temperature and humidity. • Serious heat stress can occur if the core temperature rises above 40° C for a significant period of time.

39. Adapting to Hot Weather • The body adapts in the following ways: • Blood volume increases • Heart efficiency improves • Perspiration starts sooner and increases in volume • Perspiration contains less salt

40. Adapting to Hot Weather • Increasing Body Heat Loss • Expose as much skin as possible • Wear light loose cotton clothing • Drink plenty of fluids • Acclimatize • Reducing Heat Gain from the Environment • Wear protective clothing • Seek shade • Avoid hot objects • Do not lie on ground • Decrease muscular activity

41. Nutrition and Conditioning

42. Lack of proper nutrition can cause weight loss, depression, apathy, and lack of coordination • Poor nutrition and fitness can cause fatigue, lack of endurance, lack of tolerance to heat and cold, etc.

43. The six groups of nutrients are: • Carbohydrates • Fats • Proteins • Vitamins • Minerals • Water

44. Carbohydrates include fruits, vegetables, sugar and cereals. • Protein sources include eggs, dairy products, meat, fish, poultry, nuts and peas.

45. Fat sources include butter, dairy products, meat eggs, nuts, butter, lard, cooking oil, chocolate, mayonnaise, fried foods, and ice cream.

46. Nutrition • Water makes up 60% of the body. • A sedentary person must replace 2.5 liters per day. • More is needed at altitude, hot weather, or during exertion ( 3 to 4 liters).

47. Physical Fitness • Important to members of outdoor recreation or rescue groups because their activities can impose unusual physical demands • Important to develop and maintain a high level of physical fitness

48. Fitness Program • Warm-up • Calisthenics or sports to develop motor fitness • Endurance training to develop cardiovascular fitness • Cool down period

49. Fitness • The goal and end result of any endurance sport should be to maximize the body’s ability to take up and use oxygen.

50. Fitness • A good fitness program should aim for a minimum workout of 45 minutes at least 4 times a week.