Heat Stress

1
Heat Stress

• Occurs when the body cannot maintain homeostasis
  the body temperature begins to rise
  (hyperthermia)
• Hypothalamus of brain is in control of
  maintaining body temperature (thermoregulation)
• Athletes need to be well hydrated, rested, and in
  good physical condition for temperature
  regulation to work properly
• Heat Index combines temperature humidity to
  provide a reference point for various levels of
  risk associated with exercise under hot humid
  conditions

2
Dehydration

• Symptoms subtle _at_ first.
• Light yellow urine, mild headache, fatigue
• Followed by reduced endurance oxygen uptake
• Feeling of thirst
• Serious dehydration
• disorientation irritability
• Rapid pulse
• Complete exhaustion

• 3 Levels of Dehydration
• Mild mucous membranes dry out, normal pulse,
  yellow urine, mild thirst
• Moderate extremely dry mucous membranes, weak
  rapid pulse, very dark urine, very thirsty
  feeling
• Severe completely dry mucous membranes,
  disorientation, drowsiness, no urine output,
  inability to form tears, beginning stages of
  shock

3
Dehydration, cont.

• Best treatment is prevention
• Drink 17-20 oz. 2-3 hours before activity
• 7-10 oz. after warm-up
• 28-40 oz. every hour of play
• 20-24 oz. afterward for every pound lost through
  sweat
• Sports drinks in place of water is better to
  replace carbohydrates electrolytes lost during
  intense or prolonged activity
• Adding water to a dehydrated athlete can possibly
  lead to hyponatremia

4
Sunburn

• Injury to the skin from the suns UV rays
• Medical attention sought if blisters produced
• Treatment cold washcloth OTC pain medication
• AVOID petroleum products
• Prevention use SPF 15 or greater

5
Heat Cramps

• Painful, involuntary muscle spasms caused by
  exposure to heat dehydration
• First stage of heat illness
• Caused by rapid water electrolyte loss through
  perspiration

• Occur mostly in calf muscles, can also affect
  hamstring, quadriceps, abdominal muscles
• Treatment slow, passive stretching with
  application of ice immediate fluid electrolyte
  replacement

6
Heat Syncope Heat Exhaustion

• Heat Syncope
• Occurs when body tries to cool itself through
  dilation of blood vessels
• Symptoms lightheadedness, dizziness, headache,
  nausea vomiting
• Treatment drinking fluids stopping activity

• Heat Exhaustion
• Condition of near-total body collapse, athlete
  unable to dissipate heat
• Symptoms
• Skin that is cool, moist pale
• Generalized weakness, dizziness, nausea
• Rapid breathing pulse
• Treatment
• Move athlete to shade
• Immediate fluid replacement
• Cooling the body

7
Heat Stroke

• Most severe heat related condition
• Bodys thermoregulation stops
• Symptoms
• Hot, dry, red skin
• Strong, rapid pulse
• Mental confusion
• unconsciousness

• Treatment
• Move to shade cool body immediately
• Remove clothes
• Ice towels
• Misting fanning skin
• MEDICAL EMERGENCYrequires immediate transfer to
  hospital!

8
Cold Stress

• Body loses heat in 5 ways
• Respiration rids body with each expiration
• Evaporation loss of heat through perspiration
• Conduction loss of heat through transfer to a
  cooler object
• Radiation loss of heat through transfer of
  infrared rays into cooler environment
• Convection heat loss through air currents
  passing by a warm surface

9
Cold Stress

• Factors that contribute to cold stress
• Cold temperature
• High or cold winds
• Dampness
• Cold water
• Wind chill rate of heat loss from human body
  resulting from combined effect of cold
  temperatures wind

• Wind Chill temp. is a measure of relative
  discomfort due to combined cold wind
• Effects of wind chill depend on
• Amount of clothing/protection worn
• Age, health
• Body characteristics
• Wind chill temps 0F indicate risk of frostbite

10
Hypothermia

• Occurs when body heat is lost body temp. drops
  below normal
• Symptoms begin when body temp. reaches 95F.
• Shivering, stomping feet
• Slurred speech
• Lack of coordination
• Memory loss
• Unconsciousness _at_ 85F
• Death _at_ 78F

• People whove experienced trauma may go into
  shock begin to shiverwarning sign
• As core body temp. decreases, severe hypothermia
  sets in.

11
Frostbite

• Damage to skin tissue blood vessels due to
  prolonged exposure to temp. below 32F
• 3 Stages
• Frostnip pins-and-needles sensation skin white
  soft
• Superficial frostbite blistering, skin is numb,
  waxy frozen ice crystals form in cells
• Deep frostbite freezing of blood vessels,
  muscles, tendons, nerves, bone
• Can lead to permanent damage, blood clots,
  gangrene
• No feeling is experienced in affected area
• Serious infection loss of limbs is frequent

12
Frostbite, cont.

• Emergency care should be provided immediately. If
  it is not possible to transport to a hospital,
  the following steps will help

• Bring individual indoors ASAP
• Apply warm towels or immerse the area in
  circulating lukewarm water for 20 minutes
• Leave blisters intact
• Do not use hot water or hold affected area near
  fire
• Offer warm fluids, never alcohol
• Keep the affected area raised