Methods of Transient Bodyweight Manipulation
Fluid Intake Restriction
The easiest and most body-friendly method of dehydration is fluid intake restriction. This is a sure way to delicately and quite naturally diminish the body's total water content and subsequently lighten the load.
What must be understood is that the body is constantly losing water. The routes of loss are not always obvious. There are three main routes through which the body is always losing fluid.
First and foremost is through urination. The amount varies daily due to fluid intake, diuretic influences (such as caffeine), electrolyte ingestion (salt), and state of hydration.
The body has a remarkable ability to either concentrate or dilute the urine to rid itself of waste products (namely urea( without upsetting the overall hydration method too much. That is to say, if you need to get rid of waste material but are slightly low on body wter, then your urine will be very concentrated, getting rid of the waste with as little water as possible. The body tries to conserve the water and the urine is dark.
If the body has normal hydration, it will dilute the urine and let more water go with the waste. If the body has very high hydration, it will dilute the urine greatly and it will appear clear getting rid of the excess water with little waste product in it at all.
But no matter what, some fluid is lost daily via this route. It can be a small amount of even several liters.
NOTE: 16 oz. of fluid is roughly one pound of body weight. That means that if you weigh 205 pounds on the scale, step off and chug down a bottle of Coca-Cola and step back on, you will instantly weigh 206. That's just the physical weight of the liquid in your stomach. A leter is just over 32 oz. (a quart) and can be thought of a a bit more than 2 pounds of body weight. Thus, if you were to urinate 1-1/2 liters in a day, you would be losing 3 pounds via that route. Which you would not even notice under normal circumstances because you would be replacing it through the day by drinking. But all the same it is being lost and if un-replaced will lead to weight loss.
The second route of fluid loss is usually referred to as moisture loss and occurs through the routine and unending act of breathing. The air leaving the lungs each time you exhale is 100% saturated. That's right. 100%! If you breathe on a cool pane of glass you can see for yourself all the moisture that is leaving your body every time you breathe. This has no relationship to temperature or relative humidity of the ambient air. It is always 100% saturated when it leaves regardless of how it went into the lungs.
You cannot escape this moisture loss. The only thing that affects how much total fluid is lost is how often you breathe and to some small extent how deep the ventilations are. The average breaths-per-minute is 11 to 13. The more active you are the more breaths you take, the less active, the fewer breaths you take. Still, a daily loss of around 500 ml. is not uncommon. That's about a pound. On a particularly strenuous day even more. Just by breathing!
How much moisture is lost to the air does depend on how dry the air is (remember it always leaves the body 100% saturated but it can come in wet or dry). The drier the air the more water that is taken from the body to get it fully saturated. If the air comes in moist then less moisture is needed from the body to fully saturate it. So dry climates are notorious for causing dehydration unknowingly. This is unavoidable. The only remedy is to drink more than normal (this can also work during the tail end of a dead relationship or long visits from relatives).
A third route of fluid loss is through sweating and imperceptible evaporation. It is obvious that water is lost when you are sweating. You can see and feel it on your skin. This is a normal thermoregulatory response that we are all familiar with. When you get hot your body sweats and tries to cool off. Physical exercise causes great amounts of heat to be released metabolically and the body's reaction is familiar to us all. But even if the body is quiet and inactive, sitting still in the sun at a picnic table on a 92 degree day will cause the same response. You sweat profusely! The loss can be large or small daily and depends directly on ambient temperature and activity level. Several pounds can be lost easily.
There is another type of fluid loss that occurs in this way but you never even know it. It is called imperceptible evaporation. The truth is you are pretty much constantly losing moisture through the skin. On all but the coldest of days we are all usually sweating a tiny bit. We don't see of feel it because the rate of sweat production is matched by the rate of evaporation. It never really gets a chance to accumulate on the skin. We are always losing heat this way (and moisture). The body always needs cooling. It's a machine and it's always running even at rest (you still breathe, your heart still beats, etc.). Your body temperature is over 90 degrees but you feel comfortable in the 70-74 degree range of room temperature. Why aren't you comfortable when the room is 94 degrees? At 94 degrees, you get hot! This is because as the room begins to approach the temperature of your body, it can no longer lose heat to it. And if the air temp in the room gets much over 96 your bod will begin to pick up heat from it.
So even when the room is cool, say 72 degrees, you are still losing heat to it by the evaporative pathway (as well as the conductive pathway somewhat). You don't notice this because the process of evaporation, which is dissipating the body heat, is occurring just as fast as the rate of sweat production. Again, all the same, water is lost. How much is directly related to the air humidity and temperature as well as the activity of the body. On a very dry cool day where the body active, one may never noticeably sweat yet lose over 2 pounds of fluid!
There are also small losses through various other routes such as feces and tears but they are negligible compared to he large losses that occur daily via the major routes discussed above.
What is to be understood is that with every hour that passes, water is slowly lost and if it goes un-replaced, will most definitely lead to body weight loss through dehydration with minimal effort.
All of these routes also be enhanced. But that requires effort. It requires no effort to not-do something. And by far, the easiest way to lose 3-5 pounds is to restrict water for 30-40 hours and let the body do all the work.
It becomes quite uncomfortable and of course there is considerable mental effort to avoid drinking anything. But physical effort and strain are at a minimum. This lack of physical effort can be important when trying to conserve energy prior to a big event. Thirst is a powerful motivator and some find it too overwhelming to restrict water totally. Regimes have been set up to taper water intake down and only completely restrict it for 12-20 hours. It has been my personal observation, however, that for many people it requires more discipline to moderate something than it does to abstain from it.
One way of enhancing the process is to super-hydrate the body for several days by drinking abnormally high quantities of water. This essentially tricks the body into a routine where it is constantly trying to rid itself of the excess fluid. The hormones that govern the process get used to pushing out all the extra fluid and are in high gear so to speak. Then when the intake is abruptly cut off, they continue to run full speed for quite some time before the body fully realizes what's going on. Then, of course, it's a big "whoa!" and everything begins to conserve water. But in the interim, it sets off a good start and makes the whole process more successful and easy.
I have read of programs that advise 1 gallon extra (above normal consumption) per day for 4 days. This sounds sufficient to super-hydrate but can be easily checked on the scale. The goal is to hold extra fluid and extra fluid has weight. An increase of 2 pounds minimum would show if the super-hydration was successful.
I have also seen programs that advise increases in sodium and other manipulations of key electrolytes prior to full water restriction. While the idea is sound it will probably only complicate the matter. If the athlete intends on using a diuretic to facilitate the water loss process then certain electrolyte manipulations seem justifiable, but on a simple restriction, could cause more harm than good.
Nevertheless, I have seen athletes consume copious quantities of salt with their food in the 6 days prior to sodium restriction (near total) accompanied by water restriction for 40 hours and do fairly well. But if the water restriction is to be short 20-30 hours, this will probably backfire. The body will begin to rid itself of the excess sodium (and water will follow in the urine) but possibly not have enough time to fully do the job. On long restrictions (over 40 hours without water, this is not an issue).
When the sodium is increased for 4-6 days then a period of sodium restriction is started 2 days prior to the water restriction, results are much more consistent. Hit and miss protocols can undermine weeks and weeks of training and preparation. Athletes have enough to worry about as it is. If an athlete wants to sodium load then deplete, it seems wise to begin the depletion 1-2 days prior to the water restriction and try to avoid any residual sodium retention.
Super-hydration and sodium loading can raise blood pressure significantly. Nose bleeds, headaches and cardiovascular disturbances have all been noted. Athletes with heart conditions, on heart medicines, or with blood pressure issues need to be especially careful when undergoing even the simplest of hydration manipulations. Although this is a simple technique, it has all the potential to cause dangerous health consequences.
* Fluid restriction
* Potential loss: 3-5 pounds
* Duration: 20-40 hours depending on the amount to be lost
Technique: abstain from (or taper) water consumption which includes fluids in solid foods. Super-hydration is attempted by drinking 1 gallon of water above the normal amount for 4 days prior to abstinence. A sodium loading technique can increase the results. Salt is added to the diet in larger than usual amounts for 4-6 days. 2 days prior to water restriction the sodium is removed from the diet as much as possible and remains out for the duration of the manipulation. Water is restricted for about 2 days and sodium is restricted for about 4 days prior to weigh-in.
* Effort level: exceptionally los
To health, present but low; it is a natural process
To performance: very low. Strength will be unaffected if reconstitution is sufficient.
* Up side: very easy, natural, and no strength impediment
* Down side: only a few pounds can be lost and one gets very thirsty.
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