Backpacking Notes

A collection of notes I have found helpful for planning and executing backpacking trips

4 minutes read Oct 22, 2017 Jun 7, 2017

Estimations & Rules of Thumb

  • Travel speed (upper bound) [Naismith’s rule]
    • ~3mph on flat terrain
    • ~1/2h per 1,000ft of elevation gain
  • Temperature [source]
    • Low relative humidity (ex: clear skies): ~-5.4F per 1,000ft of elevation gain
    • High relative humidity (ex: rain, snow): ~-3.3F per 1,000ft of elevation gain
    • Exceptions: Cloud cover will trap some heat, large bodies of water can increase local humidity and store heat (large thermal mass), wind chill, air streams, …
  • Water Weight [source]
    • ~2.2lb per 1L of water

Managing Local Fauna

Hanging Food Bags

  • PCT Method for Bear Bag [video]
    • Limb Selection
      • high enough so that half way up, where bag rests, is out of reach from a bear (~20ft+ limb height)
      • small enough diameter that a bear cannot climb out onto limb
      • far enough from neighboring trees to not allow other animals to jump onto the bag
    • Requirements: Carabiner, Rod/Found Branch, Bag and Cord

Managing Your Health

In General

Dehydration

Background: Water is used to transport nutrients, oxygen, waste, and heat throughout your body. ~2-3L/day lost during rest, ~1-2L/hour during strenuous exercise (varies greatly by individual).

  • Cause: water deficiency (Can be cumulative from previous days)
  • Symptoms
    • mild headache
    • feeling tired
    • thirst
    • decreased endurance (~-22% @ -1.5L, ~-50% @ -3-4L)
    • dry lips and mouth
    • dark yellow urine
    • moderate/severe: rapid, weak pulse
    • severe: cognitive disfunction (drowsy, lethargic, disoriented, irritable), no urine or tears, shock
  • Treatment: drink water

In the Cold

Background: Dry cold air removes water more rapidly when breathing (quicker evaporation/equalization).

Also see “Dehydration”.

Hypothermia

  • Cause: decreased core temperature (<90F)
  • Symptoms [source]
    • shivering
    • slurred speech
    • decreased balance, coordination
    • low energy, drowsiness
    • confusion, memory loss
    • (note: similar to being drunk)
  • Treatment: prevent cooling and get core temperature in center of body up ASAP [source]
    • find shelter from cold and wet environment (ex: set up camp)
    • immediately remove wet clothes (and replace with dry ones)
    • put on insulated garments (ex: get into sleeping bag with pad)
    • have warm high energy beverages or foods (heat + calories)

In the Heat

Background: Perspiration is composed of water and electrolytes. Hot humid air makes sweating less efficient so sweat more (slower evaporation/equalization).

Also see “Dehydration”.

Heat Exhaustion

  • Cause: ineffective hydration due to heat stress, and water and electrolyte loss
  • Symptoms
    • rapid pulse, rapid breathing
    • headache
    • nausea, dizziness, lightheaded
    • thirst
    • fatigue

    Note: (often) yellow urine, low output (occurring infrequently: 6-8 hours)

  • Treatment
    • cool down (ex: rest, shade, fanning, spray water)
    • hydrate (water + electrolytes/salt)

    Note: ~1hr to get 1L of fluid back into circulation

Heatstroke Stroke: Exertional ☠

  • Life threatening: Patient needs rapid evacuation. “Death has been known to occur within .5h of assessment”. Relapse not uncommon.
  • Cause: core temperature too high for the brain (>=105F)
    • unable to cool adequately, often dehydrated
  • Symptoms
    • sudden cognitive disfunction: disorientation, irritability, combativeness, hallucinations, bizarre delusions, incoherent speech
    • rapid breathing, rapid pulse
    • skin hot and red, wet with sweat
    • loss of coordination
    • seizures

  • Treatment

    Note: very time consuming

    • rapid cooling to improve mental functions (full body bathing but careful of drowning due to poor cognition, cooling of head and neck, fanning, spray with water)
    • rehydration (do not force fluid when cognitively impaired)
    • evacuation: see physician ASAP

Hyponatremia (Water Toxicity)

  • Cause: low blood sodium level
    • high water intake, and salt loss (sweating)
    • low salt intake (ex: not eating food or high salt beverages)

  • Symptoms:

    Note: Similar to Heat Exhaustion, EXCEPT (often) urine is “clear and copious” (occurring every few hours, several times per hour) and lack of thirst.

    • headache, lightheaded
    • weakness, fatigue
    • nausea, vomiting
    • sweaty skin
    • anxiety
    • severe: disoriented, irritable, combative
    • normal core temp., normal or slightly elevated pulse and breathing
  • Treatment
    • rest (shade)
    • stop fluid intake
    • eat salty foods (beverages often have not enough salt concentration)

Heat Cramps

Note: most likely to affect people unacclimatized to the heat and who sweat profusely

  • Cause: water and electrolyte loss (probably)
  • Symptoms: spasms of the major muscles being worked
  • Treatment
    • rest and gentle stretching
    • water + electrolytes/salt

Resources