Water - Fluids

Objectives

After reading Chapter 7 and class discussion, you will be able to: Describe the functions of water Describe the fluid composition of

the body Describe water balance Identify sources of water and %

of water in selected foods

Objectives

Discuss symptoms of dehydration Provide recommendations for fluid

replacement Define hyponatremia Discuss fluid replace beverages

Body Fluids

• Intracellular• Extracellular

– Interstitial– Intravascular

Body Water Content

@60% of body weight Brain- 75% water Blood- 85%water Skeletal muscle- 75% water Adipose- 10% water Bones- 22% water

Body Composition

60%

Functions of Water Body temperature regulation

Water absorbs excess heat Body releases fluid/heat via perspiration Skin cools as perspiration evaporates

Key transportor and solvent Blood, lymphatics, urine, digestive fluids Nutrients, oxygen; removes waste

Maintain blood volume

How much??? 8x8 rule RDI’s

Adequate Intakes 15 cups men, 11 cups women

Institute of Medicine Thirst be guide

Healthcare 1 – 1.5 ml per calorie 1800 calories = 1800 -2700 ml 240 ml/cc = 1 cup

Dehydration Fluid loss greater than intake Compounds over time Risk

Athletes, GI illness, older adults, reduced calorie intake

Contributes to Poor performance, constipation,

urinary tract infections, prolonged labor

Body Conserves Fluids

Thirst signal Vasopressin (antidiuretic

hormone) Forces the kidney to reduce urine flow Alcohol inhibits

Aldosterone hormone Signals the kidney to retain sodium,

other electrolytes

Monitor Sweat Rate

Weigh before and after Goal to replace 100% What’s lost = how much to replace

National Athletic Training Association 20-24 oz of fluid per pound lost 2-3 cups per pound

Hydration Calculator http://www.beverageinstitute.org/en_US

/pages/tools-hydration-calculator.html Factors that affect…

Gender Age Exercise

Type Intensity Length of time Temperature (humidity)

Whats In Sweat?

Electrolytes Lost in Sweat

Sodium 920–1,840 mg/l

Chloride1,062–2,478

mg/l

Potassium 156–312 mg/l

Magnesium 24–96 mg/l

17

Sodium Most Important 1 pound sweat = @ 500 mg sodium Hyponatremia

Low blood sodium Symptoms

Muscle cramps, nausea Decreases thirst before adequate hydration

Causes Hydrating without sodium (plain water) Overhydration

Add Sodium

Fluids with sodium Most clear colored sports drinks

Gatorade Powerade

Foods with sodium

College of Sports Medicine Recommends…..

Sports Drink Benefits

Flavor encourages greater fluid intake

Sodium Encourages fluid intake Helps retain fluids consumed

Most contain carbohydrates Energy Quick absorption

Hydrators Besides Water, Clear Sports Drinks….

Juice Milk Diet, caffeine free pop Caffeinated beverages Any beverage…….except alcohol Food