HeatStressGroup3

(//Rebecca-italics) (Spencer- Underlined) (Nathan- had = sign before info) (Julie- normal)

-The best defense against heat injury is hydration. Drink before your long run, drink up before you go to sleep, and drink when you wake up. You should drink about 6 - 8 glasses of water per day. Water is just fine but you may find that sports drinks will help both your recovery and your performance for runs over one hour. Most popular sport drinks have a low level of electrolytes and also contain carbohydrates to help speed up glycogen replacement. Heat Exhaustion: Heat exhaustion is caused by dehydration. The symptoms include chills, lightheadedness, dizziness, headache, and nausea. The body temperature is usually between 100 - 102 degrees and profusive sweating Heat stroke is a serious life threatening medical emergency. It is caused by a sudden failure of the thermoregulatory system of the body. The blood pressure may be low. Kidney damage occurs in about 35 per cent of cases. Rhabdomyolysis (muscle breakdown from) occurs and the myoglobulinuria (excretion of muscle breakdown products) contributes to the kidney injury. Liver damage is also evident when liver enzymes are measured following heatstroke. Disseminated intravascular coagulation also occurs in exertional heat stroke. The person will often be confused and ataxic. Seizures can occur as well as coma.
 * Medical Consequences of Heat Stress**- rebecca

90º-104º Heat cramps or Heat Exhaustion possible 105º-130º Heat cramps or Heat Exhaustion likely. Heat Stroke possible. 130º and up -Heat Stroke highly likely.
 * Apparent Temperature Heat-stress risk**

(Rebecca) **Excretory System (Skin, Sweating):** -	regulate the chemical composition of body fluids by removing metabolic wastes and retaining the proper amounts of water, salts, and nutrients. Components of this system in a person include the kidneys, liver, lungs, and skin. The excretory system helps get rid of waste products that are are not useful in the body. Some waste products are even so toxic that the body needs a system to eliminate them. The most important organs of the excretory system are the kidneys. The kidneys are placed on either side of the spinal column near the lower back. The kidneys are bean-shaped and they have an important job. They are responsible for removing wastes from the blood and they also keep your blood pressure in check and help with the making of red blood cells. When your body gets ready to pass waste products, it goes through the kidneys and mixes with water and urine. Then, the waste travels into the bladder through tubes. These tubes are called Ureters. Now, the bladder holds all of that urine until it feels so full that you need to get rid of it. That's called urination. When this happens, a tube called the Urethra takes the urine to the outside of the body.

Major Metabolic Wastes: This table summarizes the four types of metabolic wastes produced by humans (& other animals) & the type of chemical reactions that produce them. METABOLIC WASTE	A BY-PRODUCT OF .... water	dehydration synthesis & respiration carbon dioxide	cellular respiration salts	neutralization urea	protein metabolism, deamination
 * dehydration synthesis = reactions in which small molecules are combined to form large molecules
 * cellular respiration = chemical reaction that releases energy from organic molecules (usually glucose)
 * neutralization = reactions between acids & bases
 * deamination = removal of amino groups from protein molecules

Sweat is a mixture of three metabolic wastes: water, salts, & urea so as you sweat, your body accomplishes two things: sweating has a cooling effect on the body, and wastes are excreted.

-skin animation. This animation shows how the skin releases wastes in order to maintain homeostasis. The first part of this animation shows how the skin releases heat when a person has a fever. The blood vessels expand. The person’s body temperature returns to its normal temperature of 98.6† F. The second part of this animation shows how the skin releases waste, including water, salts, and urea. Waste travels through the sweat gland and out of the body through sweat pores,
 * http://www.marymount.k12.ny.us/marynet/stwbwk03/03bio/excretory/skin.html**

**2 Layers of the Skin**
 * Epidermis - outer protective layer without blood vessels
 * Dermis - inner layer containing blood vessels, sensory nerve endings, sweat and oil glands, hairs, and fat cells
 * Functions of the Skin**
 * Excretion - Wastes such as excess water, salt, urea and uric acid are removed from the body in sweat.
 * Waterproofing - The skin with its oil glands prevents the entry of water into, and loss of water out of the body.
 * Protection from Disease - The intact skin prevents invasion of micro-organisms and dust into the body.
 * Protection from Ultraviolet Rays - Pigments reduce the intake of UV rays.
 * Regulation of Body Temperature - The thin layer of fat cells in the dermis insulates the body. Contraction of small muscles attached to hairs forms 'goosebumps' and creates an insulating blanket of warm air. Also, sweat produced by sweat glands uses excess body heat to evaporate, providing a cooling effect.
 * Sensory Detection - The nerve endings or receptors in the dermis detect heat, cold, touch, pressure and pain.

=.* Body Temperature Regulation (Nervous and Endocrine System) - Julie

Body Temperature Regulation Homeostasis- regulates its internal environment so as to maintain a stable, constant condition.

Temperature (C)	Symptoms 28	   =                    Muscle failure 30	 =                      Loss of body temp. Control 33	 =                      Loss of consciousness 37	   =                    Normal 42       =              	Central nervous system breakdown 44	=                       Death*

•	In a hot environment o	The body sends a signal to the brain via the spinal cord to say the body is overheating, the brain then sends a signal back down the spinal cord and tells the body to cool itself by perspiration, which evaporates and cools the skin. o	If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs. o •	In cold weather, o	The body senses the lower temperature and our brain tells us to put more clothes on to warm ourselves up. o	When body temperature decreases below normal levels, is known as hypothermia.

•	Nervous System o	The nervous system sends messages down the spinal cord when the weather on the outside of the body is changing. The body on the inside needs to maintain a normal body temp. no matter what the temp is out side. •	Endocrine System o	Thyroid hormones regulate metabolism, therefore body temperature and weight.//

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===**Circulatory System (Heart and Blood Vessels)** - nathan The Cardiovascular system performs many tasks that assist in the maintenance of homeostasis, which prevents the effects of heat stress. The cardiovascular system assists many of the other systems in their jobs to maintain homeostasis. One of the jobs of the cardiovascular system is to supply the cells throughout the body with oxygen and glucose, and to transport the carbon dioxide to the lungs to be released. The cardiovascular system also assists in the release of heat by increasing the blood flow to the skin, where the heat is then sweated away, making the skin turn red. The increased demand for all of the previously mentioned functions causes the heart rate to greatly increase as the body works harder and more heat is created. The cardiovascular system is also required to transport other nutrients, wastes, and hormones to and from where they are needed, one of the organs that requires an especially large amount of these nutrients and hormones is the brain, which controls all the other systems.===

_Spencer--_**Salt**- Sodium is one of the main electrolytes that is in the human body. The body contains three electrolytes; sodium, potassium, and calcium, which are all able to be accessed in unrefined salts. Salt makes up all three and is necessary for the body to function. Too little or too much salt can cause cramps in the muscles, dizziness, or can also create a disturbance in your electrolytes. Drinking too much water with out the proper amount of salt intake can also have the same effects and can lead to water intoxication.


 * Water**- something that your body needs in order to function daily. It is said that the longest your body can go with out any is three days maximum. Seventy percent of the fat free mass in the body is made up of water, so it is important that the body be kept well hydrated.

A football player that is outside practicing in the hot sun needs to be drinking lots of fluids with an equal amount of salt intake in order to stay healthy. The body is able to recover quicker depending on how hydrated the person is, so a good recommendation is to be very hydrated for the temperature that you are outside with.__



Sources: images http://images.google.com/images?client=safari&rls=en&q=heat+stress&ie=UTF-8&oe=UTF-8&um=1&sa=N&tab=wi

Info http://www.deir.qld.gov.au/workplace/subjects/sunsafety/heatstress/causes/index.htm http://www.umm.edu/dermatology-info/sweat.htm http://www.sefsc.noaa.gov/HTMLdocs/heatstress.htm http://www.labour.gov.on.ca/english/hs/guidelines/gl_heat.html http://www.csao.org/uploadfiles/magazine/vol11no2/heat.htm