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COLD EXPOSURE Wind Chill

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					                                      COLD EXPOSURE
Cold exposure in general can affect many body systems. Physiological factors such as strength, power, endurance
and aerobic capacity are reduced by a drop in muscle temperature or body core temperature. The combination of
cold air and the deep breathing of exercise can trigger an asthma attack (bronchospasm). When the body and
clothing are wet (whether from sweat, rain, or snow or immersion), the cooling is even more pronounced due to
evaporation of the water held close to the skin by wet clothing.

There are two primary issues that we get concerned with when we think of cold exposure….hypothermia and
frostbite.

HYPOTHERMIA
The severity of hypothermia can vary, depending on how low the core body temperature gets. Hypothermia
frequently occurs at temperatures above freezing. There are specific signs and symptoms to look for. The
condition worsens as the core body temperature lowers. Some unique predisposing factors to hypothermia are
individuals who are diabetic and those that have an active infection of some sort. Others include being exposed to
rain, wind, or increased sweatiness.

Mild Hypothermia (core body temperature ranges from 99-95 degrees Fahrenheit):
• Involuntary shivering
• Inability to perform complex motor functions (such as skiing)
* increased blood pressure

Moderate Hypothermia (core body temperature ranges from 95-90 degrees Fahrenheit):
•Slurred speech
•Violent shivering
•Dazed consciousness
•Irrational behavior (for example, the person may begin undressing and is unaware of being cold)
• Loss of fine motor coordination

Severe Hypothermia (core body temperature ranges from 90-75 degrees Fahrenheit):
•Pupils are dilated
•Skin is pale
•Pulse rate decreases
•Muscle rigidity develops
•Shivering occurs in waves, it is violent and then pauses; the pauses eventually grow longer and longer until shivering ceases
•Person falls to the ground and cannot walk; may curl into a fetal position to conserve heat
•Person loses consciousness, heartbeat and respiration are erratic
•Cardiac and respiratory failure, then death


FROSTBITE
Frostbite is the freezing of superficial tissues, usually of the face, ears, fingers and toes. In conditions of prolonged
cold exposure, your body sends signals to the blood vessels in your arms and legs telling them to constrict
(narrow). By slowing blood flow to the skin, your body is able to send more blood to the vital organs, supplying them
with critical nutrients, while also preventing a further decrease in internal body temperature by exposing less blood
to the outside cold.
As this process continues and your extremities (the parts farthest from your heart) become colder and colder, a
condition called the hunter’s response is initiated. Your blood vessels are dilated (widened) for a period of time and
then constricted again. Periods of dilatation are cycled with times of constriction in order to preserve as much
function in your extremities as possible. However, when your brain senses that you are in danger of hypothermia
(when your body temperature drops significantly below 98.6°F), it permanently constricts these blood vessels in
order to prevent them from returning cold blood to the internal organs. When this happens, frostbite has begun.

Some factors that predispose someone to frostbite are: wet skin, windchill, dehydration, African-Americans,
women, hypotensive individuals, anemia, diabetes, and those with sickle cell disease.
                 COLD EXPOSURE (Wind Chill)
Temperature is a measure of the heat of a substance. When the forecaster tells you how warm or cold it
is going to be outside, he or she is generally referring to the temperature of the air close to the surface of
the Earth. But temperature alone will not tell you how cold you'll feel when you get outside-especially if
there is a wind blowing!

Any warm object, like a human being, will lose heat when it is exposed to cold air. The greater the wind
speed, the faster the object will lose heat. The difference between people and inanimate objects is that
we feel or sense the heat loss. A temperature we feel is called a sensible temperature. You've probably
noticed that some days feel colder than others when there is a strong wind blowing, even if the
temperatures are the same! This phenomenon is known as wind chill. To estimate the heat loss based
on temperature and wind speeds, we use the Wind Chill Index. Wind chill is referred to as an equivalent
or sensible temperature, since it is not an actual temperature.

Why should we care about wind chill? A lower wind chill can increase the rate at which certain cold-
weather dangers, such as frostbite and hypothermia can develop. There are precautions that we can
take to avoid them when outside in extreme weather, such as wearing proper clothing and using
appropriate equipment. You can also check yourself regularly for wet or cold areas on your body while
outside in extreme weather, or use the buddy system to look for signs of danger and rewarm body parts
as needed. Here are some of the conditions that can lead to hypothermia:

                    Cold temperatures        Improper dress/equipment           Wetness

             Poor food intake      Prolonged exposure         Exposed skin      Poor hydration
                           Gettysburg College Athletics
                                    Cold Exposure Guidelines

Cold weather is defined as any temperature that can negatively affect the body’s regulatory
system. These do not have to be freezing temperatures. The following temperature guidelines
have been established for Gettysburg College Athletics practice and event participation. These
temperatures will be initially determined by 3 pm and monitored throughout px times. We will
alert the coaches and A.D. if they fall within the two categories below, and then post whether the
practice is a “Caution,” “Warning” or “Termination” in the lockerrooms.

Cold Weather Caution: When temperature or wind chill (which is lower than actual
temperature) is from 40° F- 30° F
      - No modification of practice, but a warning will be given to coaches and athletes
      - Coaches and Athletic Trainers emphasizing the importance of dressing appropriately*
      - Watching those “high risk” athletes

Cold Weather Warning: When temperature or wind chill is from 30° F - 20° F, there may
be a modified outside participation of 45 minutes.
      - warm-up to be started indoors (stretching, etc) to not take away from 45 min.
      - a practice that keeps individuals moving, try to avoid working up a big sweat in the
         first 20 minutes, having them be wet, and then sit around watching.
      - Wearing a hat that covers the ears, and some sort of gloves to cover the hands are
         required.
      - Keeping a very close eye on those “high risk” athletes
      - If available, a cool-down indoors.

Cold Weather Termination: When temperature or wind chill reaches 19° F and below,
there will be a termination of outside practices.

In addition to the above guidelines it is recommended that additional directives are given to student athletes.
         -Cold exposure/activity requires more energy from the body. Additional calorie intake may be required.
         -Cold exposure can be affected by poor hydration. Dehydration affects the body’s ability to regulate
         temperature and increases the risk of frostbite.
         -Cold exposure/activity requires similar hydration to room temperature; however, the thirst reflex is not
         activated. Conscious efforts before and after practice to hydrate should be initiated.
         -Never train alone. A simple ankle sprain in cold weather may become life threatening!
         -Student-athletes should be instructed on signs of cold stress (wind chill, frostbite and hypothermia).
         Fatigue, confusion, slurred speech, red or painful extremities, swollen extremities, blurred vision, red
         watery eyes, dizziness, headache, numbness, tingling of skin and extremities, shivering, uncontrollable
         shivering etc. are a few warning signs of cold stress.

In cold weather temperatures proper layered clothing should be worn and encouraged by Gettysburg College
Athletics department staff and coaches. Clothing should be layered to allow adjustments as activity level may
increase and decrease within a practice which may elevate or drop body temperature. The first layer of clothing
should wick sweat and moisture away from the body. Equipment managers can identify what clothing works best
for this. You may have already been issued an excellent product that will act as a wick. The top layers should act as
insulators to trap heat and block wind.
These include:
          -Several layers around the core of the body, especially for those individuals that are not very active.
          -Long pants designed to insulate. On very cold days a nylon shell or wind pant can be worn on top of them
          for additional wind break.
          -Long sleeve shirt/sweatshirt/coat designed to insulate and break the wind.
          -Gloves
          -Ear protection/Hat or helmet.
          -Face protection.
          -Wicking socks that do not hold moisture inside. Wool is excellent. Cotton absorbs and holds in moisture.
                       Gettysburg College Athletics
                                Cold Exposure Policy
                                   (Home Events)
• GC Sports Medicine will check weather at least 3 days prior to game. In the event of
anticipated inclement weather, GC Sports Medicine will contact visiting Athletic Trainer to
discuss GC Cold Exposure Policy, and discuss plan of action should the weather be a concern
on the day of competition.

• After initial contact is made with visiting athletic trainer, GC Sports Medicine will check the
weather each day leading up to the game to monitor changes. Communication will be
maintained with the visiting athletic trainer should any changes occur following initial discussion.

• Temperature/wind chill reaching 30° F -20° F degrees will result in modified participation. If this
occurs, a decision will be made to implement an abbreviated version of team introductions and
national anthem, and to incorporate an extended half-time.

• Temperature/wind chill reaching 19° F degrees and below will result in termination of outside
participation.

• Individuals/groups involved with making the decision to modify participation will be:
        o GC Athletic Trainer
        o Visiting Athletic Trainer
        o Host facilities staff
        o Officials
        o Home/Visiting Coaching Staff

				
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Description: COLD EXPOSURE Wind Chill