How  many times have you formed up at ten a.m. for a battle that takes place at two p.m.? You march out; stand in the sun at a formation while the battalions form up. Stand around while a self-important buffoon makes a nonsensical “period” speech or perhaps a “period” prayer. Then we march off to the battle; sometimes close or sometimes really far away.

Once at the battle you wait in the sun. Then your line moves up. While this has been going on, you may have noticed fellow reenactors going down as heat casualties. Suddenly you don’t feel so well yourself.

The vast majority of our events take place in the summer months in what could be charitably described as a warm climate. In the course of my reenacting career I have seen more people carried off the field from heat related casualties than from any other cause.

Let’s look at the facts. We participate in events that could require us to stay in the sun for several hours during the summer in the south. We double-quick up and down the field, over hill and dale. We wear wool uniforms. On the face of it we don’t’ seem to do a lot of smart things.

You have no control over the weather. You have no control over the schedule for the event.  The one thing you can do is to drink a lot of water.

Why should you be drinking a lot of water? Okay here’s your health lesson in case you were asleep in school.

Water is an essential nutrient and it is the single most abundant component of the human body.  It makes up over 60% of your total body weight. Water helps to cushion the discs in your spine. It also helps lubricate joints.

Unlike a camel, a person cannot store water in his body. Water must be consumed regularly to ensure normal functioning of your body.

Water is found both inside and outside the cells of your body. Most water resides in muscle cells. Water in your body serves many important roles including but it is not limited to:

1.        It participates in digestion and absorption of nutrients.

2.        It aids in the excretion of waste products from the body.

3.        It is essential for maintaining blood circulation throughout the body.

4.        It maintains your body temperature.

In warm weather the average man loses 1.8 quarts of water through sweating and an additional .6 quarts of fluids from respiration per hour. Studies conducted at the U.S. Army Research Institute of Environmental Medicine show that continuous exertion in warm weather can increase water loss to as much as 28 quarts (7 gallons) in a single day.  

 How do you lose this veritable Niagara Falls of water?  There are four basic ways that you lose fluids. They are in no particular order 

1.        Breathing

2.        Urine output

3.        Sweating

4.        Stool output

You are probably familiar with the term dehydration.  How many times have you said, “Boy, am I dehydrated”? When exactly are you dehydrated?

Medically you are dehydrated when you have lost 2 % of your body weight in fluids. Let’s look at a table to examine percentages of body weigh loss and symptoms of dehydration.

Percentage of Body Weight versus Dehydration Symptoms

%	Symptoms
0	None
1	Beginning to feel thirsty
2	Increasingly thirsty
3	Dry mouth, reduced urine output; reduced blood volume
4	Feeling sick or nauseous
5	Difficulty concentrating, sleepiness, headache

 

Okay let’s do a little math in relationship to the table above. As an example we use a reenactor with a body weight of 175 pounds. One percent of his body weight is 1.75 lbs.

 We will use the earlier statement that during periods of activity in hot weather, the average man is capable of losing 2.4 quarts of water an hour.

Water weighs 8.33 lbs a gallon. There are 4 quarts in a gallon; therefore a quart of sweat weighs 2.085 lbs.

According to our chart; a loss of 4 per cent of your body weight in fluid can cause you to become a heat casualty. 4 per cent of our reenactor‘s body weight is seven pounds. Seven pounds of water translates to three and some change quarts.

To sweat out 3 and some change quarts takes just under two hours.

Simply put; dehydration is caused by failure to rehydrate on a regular basis. Rehydration is the act of replacing fluid in your body. Dehydration is a significant contributor to heat stress injuries.  Dehydration can lead to heat exhaustion, which can progress to heat stroke. Severe dehydration can lead to cardiovascular failure and death.

As a side note, it is estimated that over one third of all American’s are chronically dehydrated.[1]

Okay back to our health lesson. You are now going to be familiarized with some terms. The first term is water balance. Water balance is the term that defines whether you are hydrated or dehydrated. When you are hydrated you have a positive water balance. When you are dehydrated you have a negative water balance.

You have a built in indicator to tell if you are hydrated or dehydrated. Checking your urine is a surefire method to check your water balance. The darker your urine is; the more dehydrated you are. In addition if you are dehydrated your urine may have stronger odor.

If you are inputting enough fluids your urine should be clear and odor free. Now I can hear everyone now. I don’t want to be whizzing every fifteen minutes. This issue will be addressed a little further on.

Now what should we be drinking to replace lost fluids? There are a lot of proponents of Gatorade® or other types of  “sports” drinks. The claim is that they contain minerals and or carbohydrates that you will need to recover from periods of exertion.

You can also hang out at sutler’s row and get yourself a big soda from a local concessionaire.

For some information on what you should be drinking check out the table below.

The table will list the carbohydrate source of these sports drinks.

The table will also list Sodium and Potassium levels. As you lose fluids you will also lose Electrolytes.  Sodium and Potassium are among the elements that make up these electrolytes. These elements are vital in the regulation of your metabolism. Drinking these fluids will replace lost electrolytes; but not immediately. It takes hours if not days after ingestion for these elements to enter your system. We will discuss electrolytes a little later.

There is a term used in the table called Osmolality. You might remember the term osmosis from your science classes. Osmosis is defined as movement of a fluid as it passes through a membrane layer to an area of higher concentration (for example; water passing through a cell wall.)[2]

A simple rule of thumb concerning osmolality: The lower the number the easier it is for your body to actually absorb the fluid. Fluids with an osmolality number greater than 350 can cause stomach distress. What you can do is dilute these beverages with an equal amount of water.

 

 

COMPARISON OF FLUID REPLACEMENT BEVERAGES[3]

 

Beverage	Carbohydrate Source & Concentration	Sodium      (mg)	Potassium      (mg)	Other Nutrients	Osmolality (mOsm/L)
Gatorade®	6% Sucrose/Glucose	110	25	Chloride, Phosphorus	280-360
Exceed®	7.2% Glucose Polymers/Fructose	50	45	Chloride, Calcium, Magnesium, Phosphorus	250
Body Fuel®	4.2% Maltodextrin/Fructose	80	20	Phosphorus, Chloride, Iron, Vitamins A, B, & C	210
10-K®	6.3% Sucrose/Glucose/Fructose	52	26	Phosphorus, Vitamin C, Chloride	350
Quickkick®	4.7% Fructose/Sucrose	116	23	Calcium, Chloride, Phosphorus	305
Coca Cola®	11% High Fructose Corn Syrup/Sucrose	9.2	Trace	Phosphorus	600-715
Sprite®	10.2% High Fructose Corn Syrup/Sucrose	28	Trace	----	695
Orange Juice	11.8% Fructose/Sucrose/Glucose	2.7	510	Calcium, Niacin, Iron, Vitmins A & C, Thiamin, Phosphorus, Riboflavin	690
Water	…….	Low	Low		10-20