why hydrate?

[m3830431]

I dive at stonington...they have a portopotty...I use it...bladder is drained...I dive...if I find myself with the need to pee again, i'd talk to my Doc

At least if you can't make it it's clear.

 

[m3830431]

I also feel better and more easily maintain my weight at 145 pounds and run 2 miles at an officially clocked 15:38 minutes. Not bad for a guy who will be 52 in 3 months.

I am 52 and the only time I run is the Beer Belly race. That running is bad for you. I'd rather ride my bike and play
racquet ball. 6'2" 195 lbs. Never drank much water, Just decided it was the healthing thing to do.

 

[HowardE]

Post dive headache is often realated to dehydration? I've had that a couple of times but didn't really have anything to attribute it to.

Often times, headaches can be attributed to dehydration... A headache is a symptom of dehydration, as I understand it.

I also mentioned high altitude environment and dehydration... here's a little thing I was reading... this is from the US Army's advice to soldiers in a high altitude environment. I suppose it gives some advice that can be applied to any application.

Also... I was told that a 1 hour scuba dive burns 500 calories, so wouldn't this exection of energy require replenishment?

Dehydration
1. It is easy to become dehydrated in high-altitude environments. Dehydration increases the risk of cold injury and exacerbates the fatigue, impaired judgement and apathy of hypoxia. The body's requirement for fluids is very high at altitude; often exceeding 4 liters of water per day. This is mainly caused by increased water losses from the lungs due to the increased ventilation of cold, dry air. There is also increased urinary loss of water due to the diuretic effects of altitude and cold. Sweating due to physical exertion adds to the water loss. Especially in the first few days at altitude, there may be significant body water losses due to the vomiting associated with AMS. Diarrheal fluid losses may also be a factor. Giardia, an intestinal parasite that causes diarrhea, is common in high altitude regions. Also, the high magnesium content of glacier water, consumed as drinking water, can have a laxative effect.
2. Complicating the excessive water losses at altitude is the difficulty consuming adequate fluids. The sensation of thirst does not keep pace with water loss. Individuals do not feel like drinking, even when they are already dehydrated. AMS further exacerbates the dulling of the thirst sensation. Other symptoms of AMS include headache, nausea, vomiting, and the loss of appetite.

3. Potable water is difficult to obtain in high-altitude environments. Because of the large water requirement at altitude, a day's supply cannot be carried by an individual soldier. When temperatures are very low, water in canteens and bulk water containers may freeze, restricting water availability. It takes an exorbitant amount of time and fuel to melt snow in sufficient quantities (it takes 40 minutes to melt 4 cups of snow to make 1 cup of water).

4. All melted snow and ice, as well as water from streams, should be considered contaminated. Because at altitude water boils before it reaches 212°F (100°C), the boiling temperature of water at sea level, it needs to be boiled longer than the 10 minutes necessary for sterilization at sea level. This amounts to an additional minute for every 1000-foot gain in altitude. For example, at 14,000 feet, water needs to be boiled for 24 minutes to be purified

 

[miketsp]

..snip..
On the topic of negative net hydration from diuretics such as caffeine, National Geographic actually ran an article about it someimte in the past year. I think the general conlcusion is that although coffee and soda does increase usrine production, the additional sodium intake is beneficial, and the net hydration effect is no less than even.
..snip..

I find it hard to believe that the net effect is no less than even.
I remember a few years ago working with a colleague in a tropical country and this guy's only fluid intake (other than that naturally occuring in food) was beer, lots of it at morning, lunch and dinner, never less than 6 pints, mostly much more.
Anyway after about 6 weeks he suddenly felt unwell and passed out and we dragged him off to hospital, diagnosis - severe dehydration.

Also if you check any of the many athletic training sites most talk about a few beers the night before causing dehydration.

Example:
Quaffing one or two beers or a glass of wine the night before a race in which the weather will be cool will likely have very little effect on your performance. Before a hot weather race, however, one of the major limiting factors to your performance is your hydration level, so starting the race partially dehydrated from a few beers the night before is madness (admittedly, it is madness that I have experienced on more than one occasion).

This was written by an Olympic athlete
http://www.runningtimes.com/issues/03june/pfitz.htm

 

[IceDiverInCA]

Water intoxication can kill and is realitivly rare and requires ingesting huge quanities of wanter in a short period of time. We in the military (USAR) are aware of this condition and have lost some basic trainees to it in the warmer locations as a result of well intentioned drill Sergeants forcing them to drink to avoid heat stroke and the trainees over doing it. Symptoms are interesting enough the same as for heat exhaustion or stroke.

It's not overhydration that causes it although it contributes to this serious condition called hyponatremia. It has to do with replacing lost water during heavy sweating but not replacing electrolytes which leads to diluted blood and lowered level of sodium. This occasionally happens with endurance athletes. Divers don't have to worry about it because we don't sweat nearly as much.

Proper hydration on the other hand is important in terms of DCS. The Laplace pressure (surface tension) of water appears to keep the bubbles smaller.

 

[Wayward Son]

I find it hard to believe that the net effect is no less than even.

From the older board at scubadiving.com:

Author: DocVikingo
Date: 06-16-03 12:21

".... from your coffee drinking.

The archives yielded the following excellent treatment of this issue by our own BillP. It provides the reasoning for this conclusion:

"The main concern with the drinks you mention has to do with the effects of caffeine. Caffeine is a central nervous system (CNS) stimulant, a GI stimulant, and a diuretic.

Typical caffeine content of various drinks*:

Pepsi Cola 0.10mg/ml
Dr. Pepper 0.11mg/ml
Coca-Cola 0.13mg/ml
Mt. Dew 0.15mg/ml
Jolt 0.20mg/ml
Tea 0.28mg/ml
Coffee 0.71mg/ml

There is recent literature (see elsewhere on the board) about the potential risk of mixing pseudoephedrine (Sudafed)- another CNS stimulant- with diving, particularly with nitrox, due to the possible increased risk of O2 toxicity and seizures. I haven't seen anything specifically about caffeine's CNS stimulating effect and diving but I would suppose it would have the same theoretical concerns.

Caffeine stimulates acid secretion in the stomach and reduces the tone of the lower esophageal sphincter muscle between the esophagus and stomach in some people. Not a good combination when you might already be seasick.

Caffeine is a diuretic. It makes you pee. If you lose more fluid than you take in (for whatever reason), you become dehydrated. Dehydration increases the risk of DCS.

OK, now I'm gonna depart from the "conventional wisdom" about caffeine and diuresis for a minute here. I might be all wet with this, so if any of you have better info, feel free to chime in. Caffeine is indeed a diuretic. It makes you pee about 1ml of fluid per mg of caffeine. Coffee has (roughly) 0.71mg of caffeine per ml. So for every 1 ml of coffee you drink, you will pee about 3/4 ml of fluid. For an 8 oz (240ml) cup of coffee, you will pee an extra 170-180ml of fluid. So you're still 60-70ml of fluid ahead. If you drink coffee instead of water you will not be as well hydrated, and if you start off dehydrated (as many divers are on multi-day trips) you will be less likely to rehydrate effectively if you drink coffee instead of water. But if you drink coffee in addition to the water you would normally drink on a dive trip to maintain your hydration, the coffee won't dehydrate you."

As was mentioned in my above post, as with BillP I find the more significant issue to be that large quanities of mildly diuretic beverages like coffee will result in the diver eschewing more appropriate fluids for hydrating. Clearly the net gain of fluid is going to be less with 2-3 large coffees than with the equivalent amount of water.

Stay wet, inside & out."

DocVikingo

 

[punisher]

my conclusion...there was a lot of info here that was right on...

dyalisis patients with non working kidneys must get a certain amount of fluid removed from their bodies. thay get weighed before and after their 4 hour treatment. it gets logged everytime they do this. its that important to maintain a constant fluid amount in the body so as not to poison oneself. I don't sweat while diving. I know the water temp and wear appropiate undergarment underneath my drysuit. hence the reason I never get headache, or ever need to pee. what I drink on nondiving weeks is the same as what I drink when I dive. no more, no less. The majority of the diving world dives 45 to 65 minutes. if you're not one of them, then drink till your hearts content. for those of you out of shape, get in shape so you don't sweat your fluids away. the others, stop overdressing and you won't sweat your 2 cups of water away.

when you drink the correct amount of water for diving... you won't dehydrate and you also won't need to pee in your suit. one of the reasons the body pees is to rid itself of excess fluid. thats why its clear pee. EXCESS fluid...you don't want the flu bug so you get ONE flu shot, not 20 of them....stop overdrinking to avoid dehydration...

ladies, don't drink like the men and your drysuit will stay dry on the inside

 

[Gac]

I find it hard to believe that the net effect is no less than even.
I remember a few years ago working with a colleague in a tropical country and this guy's only fluid intake (other than that naturally occuring in food) was beer, lots of it at morning, lunch and dinner, never less than 6 pints, mostly much more.
Anyway after about 6 weeks he suddenly felt unwell and passed out and we dragged him off to hospital, diagnosis - severe dehydration.

Also if you check any of the many athletic training sites most talk about a few beers the night before causing dehydration.

Example:
Quaffing one or two beers or a glass of wine the night before a race in which the weather will be cool will likely have very little effect on your performance. Before a hot weather race, however, one of the major limiting factors to your performance is your hydration level, so starting the race partially dehydrated from a few beers the night before is madness (admittedly, it is madness that I have experienced on more than one occasion).

This was written by an Olympic athlete
http://www.runningtimes.com/issues/03june/pfitz.htm

Perhaps you misread my post. I believe that is addressed the issue of caffine as a diuretic. Beer, as well as many other forms of alcohol, should be avoided pre- and post-dive for reason of hydration et al.
The cafeine concentration found in most caffinated sodas is about 1/3-1/5 the caffeine in a typpical cup of coffee. The sodium in soda also helps to retain water. So, there is a relatively low amount of caffeine (the diuretic) in soda when compared to coffee, and the sodium in soda helps retain water.
Does that help clarify what I was saying?

 

[oceancrest67]

there's always so much talk about hydrating...I've never had the need to pee in my suit while diving...and i've never dehydrated...

are you people sweating too much under water? (overinsulated and/or out of shape)

I don't change a thing about my fluid consumption just cause I'm diving...and I only drink 2 or 3 glasses of fluid a day. Coffee with breakfast...and whatever with lunch and dinner...I've never experienced dehydration...if I sweat in my suit, I overdressed.

so what makes it so YOU have to increase your fluid intake and then need a pee valve?
I had a buddy once who said he pee'd 5 times in the ocean...prostate problem?

Just play it safe and drink plenty of water...even if you have to pee in the ocean...it is best to hydrate yourself always...reduces a dcs hit...keeps your mouth wet...etc.

Just more 02.

 

[miketsp]

While cross checking some of the figures given above I came across an interesting page with this:

75% of Americans are chronically dehydrated. (This likely applies to half the world population)
Even MILD dehydration will slow down one's metabolism as much as 3%.
One glass of water shut down midnight hunger pangs for almost 100% of the dieters studied in a University of Washington study.
Lack of water is the #1 trigger of daytime fatigue.
Preliminary research indicates that 8-10 glasses of water a day (half of that coming from food and drinks other than plain water) could significantly ease back and joint pain for up to 80% of sufferers.
A mere 2% drop in body water can trigger fuzzy short-term memory, trouble with basic math, and difficulty focusing on the computer screen or on a printed page.
Drinking 5 glasses of water daily decreases the risk of colon cancer by 45%, the risk of breast cancer by 79%, and one is 50% less likely to develop bladder cancer. Are you drinking the amount of water you should every day?

at
http://www.diagnose-me.com/cond/C5223.html