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` Water (H2O) in your body contains numerous

mineral electrolytes

` H2O makes up between 50 75% of your weight

` Leaner > H2O` An adult male 62% H2O, 17% protein, 15% fat &

6% minerals and glycogen.

` We can survive much longer without food than

without H20.

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` Participation in metabolism Nearly all chemical reaction of metabolism involved H20

pH balance

Buffer carbonic acid & bicarbonate

` Body fluids Shock absorption, lubrication (synovial fluid), cleansing

(tears) & protection (amniotic fluid)

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INTAKE

OUTPUT

* Hot environment 10-20

times more per hour

** severe diarrhea lose more

Food: 700 1000ml

Drink: 550 1500ml

Metabolic: 200 300ml

Kidney (urine): 500 1400ml

Skin*: 450 900ml

Lungs: 350ml

Feces**: 150ml

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` Based on body size & composition, activity level,

temperature & humidity.

` 2400kcal/day loses 2.4 liters (10 cups) of water

each day.` RDA- 1.0ml to 1.5ml per kcal expended.

` Athletes & very active people need much more

than this especially if they train in warm, humid

climates.

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` Our bodies maintain H2O balance by mechanisms

that control H2O intake (thirst) & H2O excretion

` Low H2O kidney conserve H2O (reabsorb H2O,

decreasing urine volume, concentrating the urine)` High H2O kidney form & excrete a large volume

of dilute urine.

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H2O Deficit

Increased [Na+] stimulatesosmoreceptors

Pituitary gland released

antidiuratic hormone (ADH)

EFFECT ON KIDNEY

conserve H2O

excrete solute in highly [urine]

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` Alcohol

` Caffeine

` Diuretic medication

` High protein diet

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` By continuous evaporation of water from the lungs

and skin, typically accounts for about one quarter

to one half of daily fluid loss

` Other factors: High altitude

Low humidity

High temperature

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` Commonly used strategies to help prevent

excessive increase in body temperature during

exercise in hot environment S

kin wetting Hyperhydration

Rehydration

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Before Event

Athletes are encourage to drink 13-20 oz (400-

600ml) or about 1 to 2 cups of fluid 2-3 hours

prior to exercise Larger athletes may consume a greater quantity

Fluid consume not just only water but carbs and

electrolytes.

Sports drinks containing 4-8% carbs are preferred

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During event

Drink a small amount of fluid: 6-12 oz (150-350ml) orabout or 1 cups of fluid every 15-20 minutes duringevent.

Additional fluid may be necessary in hot environmentand heavy sweating.

Fluid consumption maybe enhance when fluid is cooler(5-15 0C)

Fluid consumption maybe enhance when fluid is

flavored. Sports drink containing 6-8% carbs would be sufficient. Glucose, sucrose and maltodextrins are preferred over

fructose. Add sodium (0.5-0.7g/L)

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After event

Drink 16 - 33oz (500-1000ml) or about 2-4 cups of

fluid during the first 30min after event.

Fluid consumption maybe enhance when fluid iscooler and flavored.

Then consume at least 1L every 1-2 hour thereafter

until consumption has matched 150% of sweat weight

loss to allow complete rehydration.

Fluid containing carbs and electrolytes serve better

than just water alone.

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Superior hydration

Enhanced fluid consumption

Carbohydrate replacement

Electrolyte replacement Delay fatigue during exercise

Enhance performance

Examples: 100plus, Gatorade, Excel, Isomax

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Ingested fluids should be

` Cooler than ambient temperature

` Flavored for palatability

` 4-8% Carbohydrate

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Temperature Cooler solutions (5-15oC) may empty the stomach

more quickly than warmer or hot solutions.

Cooler drinks are more enjoyable and promote greater

consumption.

Osmolality and energy content High Fructose Corn Syrup has lower Osmolality than

sucrose or glucose.

Concentration of more than 8% carbohydrate in thestomach can slow down gastric emptying.

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Exercise intensityAthletes performing at higher intensities for a relatively

short time (e.g., 10km run) might benefit more fromconsuming sport drinks.

Mild to moderate exercise intensity (