Group+4-Water+and+Salt

__Hydration__ is the most important element in the prevention of heat stress. Water in the bloodstream helps our body carry nutrients to the cells and muscles. During sports, the human body burns a lot of food energy (calories). Some of that energy is used to fuel the muscles, but the rest is turned to heat. When the body begins to heat up, nerves in the skin send signals to the brain, telling it to release sweat from glands. The skin release small droplets of water that evaporate and cool the body down. However, without a large intake of water, the body cannot complete all tasks necessary to maintain a stable temperature.
 * Hydration**
 * It also helps carry waste products away from our cells and muscles.


 * By the time an athlete feels thirsty, he has already lost 1-2% of their water, and that alone is enough to hinder athletic performance.
 * A 7-10% loss can result in heat stroke or even death. Dehydration can kill.

Sweat contains between 2.25 - 3.4 grams of salt per liter. Sodium is the major extracellular electrolyte responsible for regulating water balance, pH, and osmotic pressure. Having a good amount of sodium in one's diet is important in nerve conduction. If your salt intake varies widely, these mechanisms activate to assure that your body remains healthy, maintaining a relatively constant blood pressure.
 * Salt**
 * Because of sodium's importance to your body, several interacting mechanisms guard against under-consumption of salt and its threat to your body's nerves and muscles and interference with the sodium-potassium pump.

Water: Mild dehydration (2-3% of body weight) reduces physical capacity and heat tolerance. As dehydration progresses, cognitive function deteriorates and both thermoregulation and physical capacity become seriously compromised. 5-6% dehydration is incompatible with further functioning. Chronic mild dehydration is associated with renal stones and urinary infection, severe constipation, rectal afflictions and cutaneous drying.
 * Medical Consequences:**

Salt: The spectrum of symptoms can range from mild to severe and can include nausea, muscle cramps, disorientation, slurred speech, confusion, and inappropriate behavior. As it progresses, victims may experience seizures or coma, and death can occur. Severe hyponatremia is a true medical emergency.

Sources: http://www.usariem.army.mil/heatill/prevenhi.htm http://www.angelfire.com/pro/megugirlssoccer/health/importanceofsalt.html