R
RaptorMkII
Guest
I've seen more than a few topics around asking why water is so important (and why you should be drinking so much of it).
Well, here's some info about H20 (yes I know that rhymed, I'm trying to keep you interested)
First and foremost, water is the medium through which all metabolic processes take place. If you don't have enough water in your system, things slow down, and eventually stop.
Also, water is the medium of transport for your body, blood, lymphatic system, and GI tract all require water to operate.
Water is also a temperature regulator, both because of its high heat capacity, and through its excretion in the form of perspiration (sweat).
You become thirsty when your body weight drops by ~1%. thirst is triggered by: a) decrease in volume of body fluids, b) Increase in the concentration of solutes in the blood, and c) mouth and pharynx become dry.
Thirst develops during exercise with a 1-2% loss of bodyweight
On a hot day, performance is impaired at a 2% loss of bodyweight,
On a cool day, performance is impaired at a 3% loss of bodyweight.
At 4% physical work takes more effort, you may become: Sleepy, apathetic, impatient, nauseous or even emotionally unstable
At 6% exercise temp. regulation becomes impaired, pulse rate and respiratory rate increase
At 8% loss of body mass dizziness, labored breathing, indistinct speech, increasing weakness, and confusion will set in
At 10% - spastic muscles, circulatory problems, failing kidney function
10-20% - Death
60% of the water you take in is used in your cells, 7% is in plasma, and 33% is distributed between your GI tract, Lymph system, spinal fluid, eyes, tears, and joints.
When you lose water it is from all of these areas, in proportion (to maintain osmotic pressure).
Now for the bits that most of you are interested in:
When you exercise you lose around 4 pounds of water per hour by sweat. However, you can only absorb water at a rate of 2 pounds per hour (or 1 cup every 15 minutes).
If you exercise daily and but don't make a concerted effort to replace the water you lose, you will become chronically dehydrated.
In a topic about running in garbage bags, Squatch added: If you sweat too much and don't replenish the electrolytes that your body loses during sweating you can also cause health issues. Electrolytes control alot of body functions, including the Na/K pump, electrical impulses, etc.
In the same topic Amalthea posted: The electrolyte imbalance caused on a regular basis will also cause kidney damage, which means your blood will not be filtered properly. If this is occurring while exercising, your body wont be able to compensate for the respiratory alkalosis, causing an increase in you blood (and cellular) ph, and your enzymes will be thrown off balance
The amount of water you need is largely dependent on you, your diet and exercises routine. The most common rule of thumb around here is to drink a gallon a day.
The most concrete formula I've found is to drink about 1.5 grams of water per calorie expended. So if you burn 500 calories on the elliptical, that's 750 grams of water you need to drink, or 1.65lbs, or 3.3 cups (26.4oz). Though, personally I round up to 2g/c to make the math easier, and to make sure I get enough.
In the other topic, Ginamj added: Just thought I'd add another way to calculate water needs. Weigh prior to exercise and immediately after. The weight loss is what you need to replace in fluids. To do this take the amount lost and multiple by 16 to get ounces of water you need to consume. You should aim to drink at least 80% of this amount.
For example 2lbs lost x 16 = 32ounces
32 ounces x .80 = ~25 1/2 ounces (drink at least this amount to replace fluids lost during exercise)
You will need more water if:
a) You're on a high protein diet (which I address with the 2g/c)
b) You eat salty foods
c) You eat a diet high in whole grains and fiber
d) You don't regularly drink caffeinated beverages (If you drink caffeinated beverages regularly, your body adapts to the caffeine, and your water needs decrease (as opposed to what you'd need if caffeine was a once-in-a-blue-moon kind of thing for you))
Okay, I think that about covers it.
I hope that helped
One final note; If anybody has anything to add, as always, feel free.
Well, here's some info about H20 (yes I know that rhymed, I'm trying to keep you interested)
First and foremost, water is the medium through which all metabolic processes take place. If you don't have enough water in your system, things slow down, and eventually stop.
Also, water is the medium of transport for your body, blood, lymphatic system, and GI tract all require water to operate.
Water is also a temperature regulator, both because of its high heat capacity, and through its excretion in the form of perspiration (sweat).
You become thirsty when your body weight drops by ~1%. thirst is triggered by: a) decrease in volume of body fluids, b) Increase in the concentration of solutes in the blood, and c) mouth and pharynx become dry.
Thirst develops during exercise with a 1-2% loss of bodyweight
On a hot day, performance is impaired at a 2% loss of bodyweight,
On a cool day, performance is impaired at a 3% loss of bodyweight.
At 4% physical work takes more effort, you may become: Sleepy, apathetic, impatient, nauseous or even emotionally unstable
At 6% exercise temp. regulation becomes impaired, pulse rate and respiratory rate increase
At 8% loss of body mass dizziness, labored breathing, indistinct speech, increasing weakness, and confusion will set in
At 10% - spastic muscles, circulatory problems, failing kidney function
10-20% - Death
60% of the water you take in is used in your cells, 7% is in plasma, and 33% is distributed between your GI tract, Lymph system, spinal fluid, eyes, tears, and joints.
When you lose water it is from all of these areas, in proportion (to maintain osmotic pressure).
Now for the bits that most of you are interested in:
When you exercise you lose around 4 pounds of water per hour by sweat. However, you can only absorb water at a rate of 2 pounds per hour (or 1 cup every 15 minutes).
If you exercise daily and but don't make a concerted effort to replace the water you lose, you will become chronically dehydrated.
In a topic about running in garbage bags, Squatch added: If you sweat too much and don't replenish the electrolytes that your body loses during sweating you can also cause health issues. Electrolytes control alot of body functions, including the Na/K pump, electrical impulses, etc.
In the same topic Amalthea posted: The electrolyte imbalance caused on a regular basis will also cause kidney damage, which means your blood will not be filtered properly. If this is occurring while exercising, your body wont be able to compensate for the respiratory alkalosis, causing an increase in you blood (and cellular) ph, and your enzymes will be thrown off balance
The amount of water you need is largely dependent on you, your diet and exercises routine. The most common rule of thumb around here is to drink a gallon a day.
The most concrete formula I've found is to drink about 1.5 grams of water per calorie expended. So if you burn 500 calories on the elliptical, that's 750 grams of water you need to drink, or 1.65lbs, or 3.3 cups (26.4oz). Though, personally I round up to 2g/c to make the math easier, and to make sure I get enough.
In the other topic, Ginamj added: Just thought I'd add another way to calculate water needs. Weigh prior to exercise and immediately after. The weight loss is what you need to replace in fluids. To do this take the amount lost and multiple by 16 to get ounces of water you need to consume. You should aim to drink at least 80% of this amount.
For example 2lbs lost x 16 = 32ounces
32 ounces x .80 = ~25 1/2 ounces (drink at least this amount to replace fluids lost during exercise)
You will need more water if:
a) You're on a high protein diet (which I address with the 2g/c)
b) You eat salty foods
c) You eat a diet high in whole grains and fiber
d) You don't regularly drink caffeinated beverages (If you drink caffeinated beverages regularly, your body adapts to the caffeine, and your water needs decrease (as opposed to what you'd need if caffeine was a once-in-a-blue-moon kind of thing for you))
Okay, I think that about covers it.
I hope that helped
One final note; If anybody has anything to add, as always, feel free.
