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Water - Essential Macronutrient For All Energy
Production
Water
Water is essential for all energy production in the body. Water
is also used for temperature regulation and waste elimination and
is essential to cell processes. An inadequate supply of water can
result in up to a 30% reduction of energy. Between 50% and 70% of
the body weight is water. Insufficient water in the body results
in a decrease of blood volume thereby reducing the overall oxygen
transport ability of the blood to properly supply the muscles during
exercise. Since blood is used to regulate body temperature, inadequate
cooling of the body occurs. The heart rate increases as the cardiovascular
system is stressed and overheating occurs leading to possible heat
stroke or heat exhaustion. We can survive without other nutrients
for several weeks. However, we can only survive without water for
about one week. Water is used to emulsify solutions within the body
and transport them to the various tissues including the transport
of waste byproducts.
Thirst is not an accurate measure of the body's water requirement.
Age and environment alter the thirst mechanism. Therefore, a quantitative
schedule must be utilized to adequately hydrate the body. Two hours
prior to exercising in a hot environment, the participant should
consume 2-3 cups of water and another 1-2 cups about 15 minutes
before exercising. During exercise, about 4 ounces of water should
be consumed every 15 minutes to replace water lost through sweat
and maintain blood volume. As a guide for each pound of body weight
lost through sweating while exercising, drink two 8oz. glasses of
water. A loss of only two-percent of body weight through sweating
can bring on the onset of dehydration. Adults should drink about
2 1/2 quarts of water per day.
Early signs of dehydration include dizziness, fatigue, headache,
and loss of appetite. Advanced dehydration is manifested by rapid
pulse, shortness of breath, deep yellow urine, blurred vision and
hearing loss.
Cold water is absorbed into the body from the stomach faster than
warm water. Recent studies suggest that drinks containing up to
10% sugar are almost as readily absorbed from the stomach. These
sugary drinks have been shown to improve endurance in events lasting
2 to 3 hours. However, for fat burning purposes, consumption of
sugary drinks will provide carbohydrate energy to the exercising
muscles and possibly stave off fat metabolization for use as energy.
Therefore, if your intent is performance, then consume sports drinks.
However, if the purpose of the exercise session is to burn fat,
then drink water only. The glycogen stores in the muscles will run
out in about 20 minutes and the body will be forced to metabolize
stored fat for continued energy.
Consumption of salt in excess of recommended dietary requirements
draws water out of the cells thereby impairing cellular function.
Salt depletion may occur during endurance type exercises and when
consuming water only. Salt tablets are not recommended because they
draw water out of the body and into the stomach. In cold weather,
urine production is increased therefore it is just as important
to properly hydrate in cold weather environments as it is in hot
weather.
Fitness Guide
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Content Provided by International Fitness Association
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