10 Things You Need to Know About Dehydration and How to Avoid it


Many years ago, I was on a mountain climbing its vertical walls and shooting for a TV program. The shooting and the climb took the whole day and we spent the night at the summit, as more shooting was about to happen the very next morning.

All this was planned; including a helicopter bringing bottled water. But the helicopter couldn’t land on this diminutive summit so the crew dropped the water bottles from the air, blowing them up on impact.

The next day, going down was long and tortuous and I had a thirst like I never felt before. I knew this mountain way too well to know how long it would take me to get to the bottom and sip some cool liquid.

This all happened in Brazil and the luxurious rain forest gave us some water on the way down. Don’t ask me about the bugs in the water, as my body needed the liquid more than my fear of catching anything.

An old pen case served as a straw to catch the few sips of water a bromeliad would give me, or a rain puddle on the plateaus. The descent took us the whole day and I was raving crazy with the lack of water.

A sport drink awaited me at the end of the trail where I finally got the time to properly hydrate my dehydrated body. This happened almost twenty years ago and I still can feel my dry throat and my desperation as we descended that mountain.

Dehydration is a performance killer.

If you practice any physical activity, you know how important it is to stay hydrated. Robert W. Kenefick, Ph.D., a physiologist with the U.S. Army Research Institute of Environmental Medicine identifies "Being more than two percent dehydrated in warm environments causes a decline in performance”.

Pure water is not all bad; actually it is still important in correcting dehydration when one is not engaged in activity. For performance it is the incomparable second best, but at one point it will limit the performance from both the intensity and the length of time of the exercise when compared to what a sport drink delivers.

"It's pretty common for athletes to hit at least one or two percent dehydration during endurance events," according to Craig Horswill, Ph.D., senior research fellow at the Gatorade Sports Science Institute. "The body's temperature-regulating mechanism is affected even at one percent dehydration." And you are seriously dehydrated when you have lost five percent of your body weight.

On the other hand, over-hydration (hyponatremia) is also serious and in step-wise stages can cause an individual to initially under-perform, followed by sloppy execution of a task, progressing to delirium, the penultimate step being coma and finally, death at the extreme.

Hyponatremia occurs when you are incessantly drinking large volumes of water well beyond your fluid loss, resulting in lowering of blood-sodium levels. Who can be most affected?  Women, slower runners and beginning exercisers are those with increased risk.

Heinz Valtin, M.D, a hydration expert and professor emeritus at Dartmouth Medical School in Hanover, N.H, estimates that it would take almost 15 liters of water for a healthy person to develop significant hyponatremia.

Below you will find a compilation of facts and suggestions about hydration to help you understand your body signs of dehydration – or over-hydration and how to avoid it.

1. Drink only when you are thirsty and not at every fluid station during a running or outdoor activity. For years runners have been urged to drink ahead of their thirst — the message being that by the time you feel thirsty, you're already on the road to dehydration. But in reality, this has changed and now the IMMDA guideline, established in 2002, suggests athletes should drink responding to thirst during the race, not exceeding 800 ml/hr (Timothy D. Noakes, in Waterlogged).

"Humans evolved the thirst mechanism over millennia," states Timothy D. Noakes, M.D, professor of exercise and sports science at the University of Cape Town, South Africa, and author of Lore of Running and Waterlogged: The Serious Problem of Overhydration in Endurance Sports. "It is the only system used by all other creatures on this earth. Why should it not also be ideal for humans?"

Hydration is measured by blood sodium concentration  - the higher the concentration, the more dehydrated you are. When this concentration increases by just two percent, you get thirsty.

2. If your activity is over 30 minutes, consider taking sports drinks instead of water because they contain both carbohydrate (for energy) and electrolytes. Many individuals don’t tolerate drinking large quantities of pure water and, as a result, they don't drink all that they need or they skip out on hydration altogether. If you opt for energy or sports drink, you're more likely to drink larger volumes, thereby avoiding the exercise-induced dehydration.

Fluids are absorbed through the gut and into the bloodstream faster when their osmolality closely resembles that of the body fluid, blood. (This ratio of the two is very important in the gut!) Osmolality is the concentration of dissolved particles in a fluid. Sports drinks contain a specific relative concentration of these dissolved mineral salts (sodium etc) compared to carbohydrates where pure water doesn't. It is noted that pure water isn’t absorbed as readily comparatively.

Why? First remember, the key to enhancing water absorption is it chases sodium (mineral salt) absorption across membranes. This specific ratio of the carbohydrates to sodium combination allows this unit to access one of the major transport pumps in the intestines that quickly transports the carbohydrate – sodium combination efficiently across the intestinal membrane into the blood stream where you need them. The water that makes up the sport drink in your intestines rushes after the sodium across the intestinal wall into the blood stream to maintain a balanced concentration – so, more important than the exact concentrations is the ratio of one to the other.

It should be clear that primarily sodium and other minerals play the important role of regulating fluid balance in the body, the former in the blood stream, the latter within the cell.

The mantra is water follows sodium ions.

In other words, they help determine how much fluid enters or does not enter into muscle fiber cells and other cells, how much remains in the blood, and so on. Because sports drinks contain these nutrients, they do a better job of allowing the body to maintain optimal fluid balance, intensity and duration of performance, which is an important aspect of hydration that few athletes consider.

Conclusion: Choose sports drink that contains optimally 15 mg of sodium per oz.

Sports drinks have other advantages over water. The calories in sports drinks, if not taken in excess, does improve the length of the performance, may limit immune system suppression that sometimes follows hard workouts, reduce exercise-induced muscle damage, and promote faster recovery.

3. About 35% of water intake comes from food, while 45 to 50% comes from drinking water and beverages (caffeinated included but alcohol excluded), and the rest from metabolism, says Stephen Rice, MD, PhD, MPH, sports medicine specialist at the Jersey Shore Medical Center in Neptune, NJ.

Water is excreted from the body in multiple forms: through urine and feces, through sweating, and by respiration of water vapor in the breath. With physical exertion and heat exposure, water loss will increase and daily fluid needs may increase as well.

The cold dry of winter should not be excluded when the most significant water loss happens through breathing – and sweating. Skiers and snowboarders are exhausted at the end of the day, for example, because the cold sucks the water from their bodies, through breathing and sweating.

4. Can we ‘store’ water? "That doesn't work," says Heinz Valtin. "Assuming we're healthy (and in fluid balance), all liquids we drink will be out of our bodies within a half-hour. So you can't store up your liquids."

5. To measure water loss after a workout, weigh yourself (with little or no clothing) before and after one hour of hard exercise with no fluid intake immediate prior to jumping on the scale. The change in body weight reflects sweat loss and respiratory losses. A one-pound drop in weight equates to loss of 16 oz. of sweat. A two-pound drop equates to 32 oz.—that's one quart. Drink accordingly during your workouts to prevent that loss.

This can determine the amount of water you need replace (80 to 100 percent) of what is lost. Approximately 16 ounces of water should be consumed for every pound lost.

Maintaining proper fluid balance is essential during exercise, when your muscles generate 20 times more heat than at rest. There is no one-size-fits-all recommendation for fluids, so pay attention to your own sweat loss and hydrate accordingly. Source: Sports Nutrition Guide Book by Nancy Clark

6. How much water do we need daily? No scientific evidence supports the "eight glasses per day" rule, so you can simply drink in response to thirst. You can also monitor your urine. If your urine is scanty, dark and smelly, you should drink more. If you have not urinated during your work or school day (8 a.m. to 3 p.m.), you are significantly under-hydrated.

7. Drink tap water and get hydrated the same way as you would by drinking bottled water!

Check the video below.

8. Common signs of dehydration - If you find someone with these signs, seek a doctor immediately:

  • General fatigue,
  • Dizziness,
  • Loss of appetite,
  • Flushed skin,
  • Nausea,
  • An increase in body temperature (an eminent sign),
  • Dark-colored urine,
  • Weakness and clumsiness,
  • Muscle cramps, and
  • Seizure-like activity.

Note that there can be milder forms of each of these, being indicators that things are going the wrong direction and seeking earlier medical attention is better than the documented bad outcomes of delaying help.

9. Common signs of over-hydration (hyponatremia) – similar to dehydration:

  • Disorientation,
  • Nausea,
  • Muscle weakness.

10. A lean body mass contains 70% to 75% of water. We can last for some time without food but we don’t survive more than a few days without water.

Water is the solvent for our biochemical reactions.

  • Blood is approximately 93 percent water - the remainder cells and solute.
  • Muscle is about seventy three percent water.
  • Body fat is about 10 percent water.

How do you maintain a solid hydrated state during an activity?

The Story of Bottled Water (2010)

The Story of Bottled Water (2010)

http://storyofbottledwater.org The Story of Bottled Water, released on March 22, 2010 (World Water Day) employs the Story of Stuff style to tell the story of manufactured demand—how you get Americans to buy more than half a billion bottles of water

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