Proper Hydration for Exercise - Water or Sports Drinks

What and when athletes drink depends upon exercise duration and intensity

Water is the most essential ingredient to a healthy life. Water has many important functions in the body including:
- Transportation of nutrients / elimination of waste products.
- Lubricating joints and tissues.
- Temperature regulation through sweating.
- Facilitating digestion.
- Importance of Water During Exercise

Proper hydration is especially important during exercise. Adequate fluid intake for athletes is essential to comfort, performance and safety. The longer and more intensely you exercise, the more important it is to drink the right kind of fluids.

Dehydration
Athletes need to stay hydrated for optimal performance. Studies have found that a loss of two or more percent of one's body weight due to sweating is linked to a drop in blood volume. When this occurs, the heart works harder to move blood through the bloodstream. This can also cause muscle cramps, dizziness and fatigue and even heat illness including:

Heat Exhaustion
Heat Stroke

Causes of Dehydration
Inadequate fluid intake
Excessive sweating
Failure to replace fluid losses during and after exercise
Exercising in dry, hot weather
Drinking only when thirsty

Hyponatremia - Water Intoxication
Although rare, recreational exercisers are also at risk of drinking too much water and suffering from hyponatremia or water intoxication. Clearly, drinking the right amount of the right fluids is critical for performance and safety while exercising.

Adequate Fluid Intake for for Athletes
Because there is wide variability in sweat rates, losses and hydration levels of individuals, it is nearly impossible to provide specific recommendations or guidelines about the type or amount of fluids athletes should consume.

Finding the right amount of fluid to drink depends upon a variety of individual factors including the length and intensity of exercise and other individual differences. There are, however, two simple methods of estimating adequate hydration:

Monitoring urine volume output and color. A large amount of light colored, diluted urine probably means you are hydrated; dark colored, concentrated urine probably means you are dehydrated.
Weighing yourself before and after exercise. Any weight lost is likely from fluid, so try to drink enough to replenish those losses. Any weight gain could mean you are drinking more than you need.

Things that Affect Fluid Loss in Athletes
High altitude. Exercising at altitude increases your fluid losses and therefore increases you fluid needs.
Temperature. Exercising in the heat increases you fluid losses through sweating and exercise in the cold can impair you ability to recognize fluid losses and increase fluid lost through respiration. In both cases it is important to hydrate.
Sweating. Some athletes sweat more than others. If you sweat a lot you are at greater risk for dehydration. Again, weigh yourself before and after exercise to judge sweat loss.
Exercise Duration and Intensity. Exercising for hours (endurance sports) means you need to drink more and more frequently to avoid dehydration.

To find the correct balance of fluids for exercise, the American College Of Sports Medicine suggests that "individuals should develop customized fluid replacement programs that prevent excessive (greater than 2 percent body weight reductions from baseline body weight) dehydration. The routine measurement of pre- and post-exercise body weights is useful for determining sweat rates and customized fluid replacement programs. Consumption of beverages containing electrolytes and carbohydrates can help sustain fluid-electrolyte balance and exercise performance."

According to the Institute of Medicine the need for carbohydrate and electrolytes replacement during exercise depends on exercise intensity, duration, weather and individual differences in sweat rates. [They write, "fluid replacement beverages might contain ~20–30 meqILj1 sodium (chloride as the anion), ~2–5 meqILj1 potassium and ~5–10% carbohydrate."] Sodium and potassium are to help replace sweat electrolyte losses, and sodium also helps to stimulate thirst. Carbohydrate provides energy for exercise over 60-90 minutes. This can also be provided through energy gels, bars, and other foods.

What about Sports Drinks?
Sports drinks can be helpful to athletes who are exercising at a high intensity for 60 minutes or more. Fluids supplying 60 to 100 calories per 8 ounces helps to supply the needed calories required for continuous performance. It's really not necessary to replace losses of sodium, potassium and other electrolytes during exercise since you're unlikely to deplete your body's stores of these minerals during normal training. If, however, you find yourself exercising in extreme conditions over 3 or 5 hours (a marathon, Ironman or ultramarathon, for example) you may likely want to add a complex sports drink with electrolytes.

General Guidelines for Fluid Needs During Exercise
While specific fluid recommendations aren't possible due to individual variability, most athletes can use the following guidelines as a starting point, and modify their fluid needs accordingly.

Hydration Before Exercise
Drink about 15-20 fl oz, 2-3 hours before exercise
Drink 8-10 fl oz 10-15 min before exercise
Hydration During Exercise

Drink 8-10 fl oz every 10-15 min during exercise
If exercising longer than 90 minutes, drink 8-10 fl oz of a sports drink (with no more than 8 percent carbohydrate) every 15 - 30 minutes.

Hydration After Exercise
Weigh yourself before and after exercise and replace fluid losses.
Drink 20-24 fl oz water for every 1 lb lost.
Consume a 4:1 ratio of carbohydrate to protein within the 2 hours after exercise to replenish glycogen stores.

Source:

Consensus Statement of the 1st International Exercise-Associated Hyponatremia Consensus Development Conference, Cape Town, South Africa 2005. Clinical Journal of Sport Medicine. 15(4):208-213, July 2005.

Exercise and Fluid Replacement, ACSM Position Stand, American College Of Sports Medicine, Medicine and Science In Sports & Exercise, 2007.

Institute of Medicine. Water. In: Dietary Reference Intakes for Water, Sodium, Cholride, Potassium and Sulfate, Washington, D.C: National Academy Press, pp. 73–185, 2005.

By Elizabeth Quinn, MS (Sports Science), About.com
Updated: January 23, 2008

High Protein Diets Can Cause Dehydration, Even in Athletes!

Study findings: A diet high in protein silently caused dehydration in endurance athletes, individuals whose training gave them a greater capacity to adapt to dehydration than the average person.

Speaking at the Experimental Biology 2002 meeting in New Orleans on Monday, April 22, William Forrest Martin, a graduate student in the laboratory of Dr. Nancy Rodriguez, University of Connecticut, reported an unique study comparing the hydration status of five endurance athletes as they consumed low, moderate, and high amounts of protein for four weeks at each level. Adjusted for weight, based on a 150 pound individual, the daily protein intake was 68 grams daily for the low protein diet, 123 grams for the moderate protein diet, and 246 for the high protein diet. Although these athletes were not trying to lose weight, the high protein diet they consumed was roughly 30 percent of total caloric intake, proportionally comparable to many popular high protein diets.

As the amount of protein consumed went up, the degree of hydration progressively went down. During the period in which athletes were consuming the highest amounts of protein, their blood urea nitrogen (BUN) - a clinical test for proper kidney function - reached abnormal ranges. Other tests indicated that the high protein diet caused the kidney to produce a more concentrated urine. The researchers believe the bottom line is clear for athletes and non-athletes alike: when consuming high protein diets, increase your fluid intake, whether you feel as if you need to or not. The athletes in this study reported no difference in how thirsty they felt and consequently they did not drink more liquid from the low to high protein diets. Athletes or extremely active people may also want to monitor hydration status.

In fact, say the researchers, you might want to drink more water regardless of your diet. It has been estimated that three of every four Americans are chronically dehydrated, placing themselves at increased risk for heat illness and other health problems. As little as a two to three percent decrease in body water has been found to negatively affect performance and cardiovascular function.

Source: www.sportsnutrition.about.com

Hydration: Does It Always Have To Be Water?

Whether you’re an elite athlete, an avid exerciser, or more the
spectator type, there’s one common fact: you can’t live long
without water. Your body needs enough water to carry out
many vital body functions and help you perform at your best.
That’s why it’s so important to stay hydrated both on and off
the field, says fitness expert, author and celebrity trainer,
Kathy Kaehler. “Proper hydration keeps our bodies running
the way they’re supposed to,” she says.

Read on to learn the ins and outs of hydration, as well as
some surprising facts about caffeine and hydration.

Fulfilling Daily Water Needs

Being hydrated means the water you consume from beverages
and foods is in balance with the water your body loses from
perspiration, respiration, elimination and other body processes.
The term “water” can mean more than just plain drinking water
in this case. It includes other liquids such as milk, fruit juices,
sports drinks, and watery foods such as fruits and vegetables,
and even beverages such as soft drinks, coffee, and tea. The
Institute of Medicine (IOM) recommends a daily water intake of
91 ounces for healthy women and 125 ounces for healthy
men. Water needs increase with factors such as strenuous
physical activity, hot and cold temperature extremes, and
being ill with fever, diarrhea or vomiting. About 80% of water
intake comes from beverages and about 20% comes from foods.

Surprising Facts about Caffeine and Hydration

You may be surprised to learn that caffeinated beverages are
not dehydrating, as is commonly believed. A 2004 report from
the IOM concluded that caffeine-containing beverages such as
regular coffee, tea and soft drinks contribute to total daily water
intake, similar to beverages without caffeine. Although caffeine
has a mild diuretic effect, it does not generally contribute to
dehydration because the fluid in the beverage itself cancels out
any fluid loss from the body. In fact, all beverages have a mild
diuretic effect, even water.

So, how much caffeine is okay?

According to scientists, moderate caffeine intake of up to 300
milligrams (mg) per day does not cause adverse effects for most
people. However, individual sensitivities to caffeine may vary, and
certain sub-populations such as children and pregnant women,
as well as those with a history of heart attack and/or high blood
pressure, may experience increased sensitivity to caffeine. These
groups should monitor their caffeine intake and talk to a physician
about their consumption levels. Like others, athletes should keep
caffeine intake to a moderate level of around 300 mg per day and
note the caffeine content of commonly consumed foods and
beverages such as coffee, tea, soda, chocolate milk, energy drinks
and dark chocolate. The chart below can help you gauge your daily
caffeine intake.

Know the Warning Signs of Dehydration

Thirst is often the first alert that your body needs water, but
don’t rely on it alone when you work out hard or in hot
conditions—drink “proactively” whether you’re thirsty or not.
Other symptoms of dehydration include dry mouth, swollen
tongue, weakness, dizziness, confusion, sluggishness or fainting.
Dehydration may also lead to muscle cramps in athletes—another
important reason to stay hydrated during rigorous exercise.
Often a urine check is the easiest way to judge hydration status.
Pale yellow or almost colorless urine signals that you’re drinking
enough. It’s time to drink up if your urine is small in volume,
strong-smelling or dark in color (although taking certain vitamins
and dietary supplements may also temporarily darken urine color).
Though rare, it’s possible to drink too much fluid and dilute the
body’s sodium levels. This dangerous condition is called
hyponatremia. But keep in mind that, for the vast majority of
athletes, the biggest concern is dehydration caused by
not drinking enough fluids. Work with your trainer, coach or
sports nutritionist to determine the optimal amount of fluids for you.
Coaches and trainers can promote proper hydration by providing
plenty of water, sports drinks and other preferred beverages at
workout sessions, practices and events, and encouraging athletes
to drink whenever they want, rather than waiting for a specific break time.

Article courtesy of www.ific.org

Can You Really Drink Too Much Water?

By Anne Marie Helmenstine, Ph.D., About.com

Can You Really Drink Too Much Water?

In a word, yes. Drinking too much water can lead to a condition known as water intoxication and to a related problem resulting from the dilution of sodium in the body, hyponatremia. Water intoxication is most commonly seen in infants under six months of age and sometimes in athletes. A baby can get water intoxication as a result of drinking several bottles of water a day or from drinking infant formula that has been diluted too much. Athletes can also suffer from water intoxication. Athletes sweat heavily, losing both water and electrolytes. Water intoxication and hyponatremia result when a dehydrated person drinks too much water without the accompanying electrolytes.

What Happens During Water Intoxication?

When too much water enters the body's cells, the tissues swell with the excess fluid. Your cells maintain a specific concentration gradient, so excess water outside the cells (the serum) draws sodium from within the cells out into the serum in an attempt to re-establish the necessary concentration. As more water accumulates, the serum sodium concentration drops -- a condition known as hyponatremia. The other way cells try to regain the electrolyte balance is for water outside the cells to rush into the cells via osmosis. The movement of water across a semipermeable membrane from higher to lower concentration is called osmosis. Although electrolytes are more concentrated inside the cells than outside, the water outside the cells is 'more concentrated' or 'less dilute' since it contains fewer electrolytes. Both electrolytes and water move across the cell membrane in an effort to balance concentration. Theoretically, cells could swell to the point of bursting.
From the cell's point of view, water intoxication produces the same effects as would result from drowning in fresh water. Electrolyte imbalance and tissue swelling can cause an irregular heartbeat, allow fluid to enter the lungs, and may cause fluttering eyelids. Swelling puts pressure on the brain and nerves, which can cause behaviors resembling alcohol intoxication. Swelling of brain tissues can cause seizures, coma and ultimately death unless water intake is restricted and a hypertonic saline (salt) solution is administered. If treatment is given before tissue swelling causes too much cellular damage, then a complete recovery can be expected within a few days.

It's Not How Much You Drink, It's How Fast You Drink It!

The kidneys of a healthy adult can process fifteen liters of water a day! You are unlikely to suffer from water intoxication, even if you drink a lot of water, as long as you drink over time as opposed to intaking an enormous volume at one time. As a general guideline, most adults need about three quarts of fluid each day. Much of that water comes from food, so 8-12 eight ounce glasses a day is a common recommended intake. You may need more water if the weather is very warm or very dry, if you are exercising, or if you are taking certain medications. The bottom line is this: it's possible to drink too much water, but unless you are running a marathon or an infant, water intoxication is a very uncommon condition.

Hydrate Using Food?

UW SPORT NUTRITION
Having Trouble Drinking Your 8 Glasses Of Water?
FOOD to the RESCUE!

How much water/fluid do you need per day?
_________your weight (lbs) / 2 = ___________ ounces of water per day (at least)Example: 140 lbs / 2 = 70 ounces per day (at least)

Water makes up 70% of our muscles and 75% of our brains. In addition, water regulates our body’s temperature, speeds our digestion and carries nutrients to our cells. Therefore, it is essential to stay hydrated, especially on these hot summer days ahead. Guzzling 8 glasses of water a day can be a pain in the butt! Luckily there are plenty of ways to get the amount of water you need every day without drinking it!

Don’t forget about the food pyramid! Eat your fruits and vegetables. About 20% of our hydration needs come from fruits and veggies. Tea and coffee also help fulfill our needs, but try not to drink more than two cups per day.

The following foods can help you get the amount you need:
Cobb salad with mixed greens - 9 oz
15 baby carrots 4.5 oz
1 cup of coffee 8 oz
1 cup of grapes 4 oz
1 cup of chicken noodle soup 7 oz
1 container of yogurt 4 oz
1 cup orange juice 7 oz
1 frozen juice bar 2.5 oz

During workouts you need to drink 8-10 ounces every 30 minutes (at least). Having carbs in your beverage allows you to play longer without running out of energy. You may need extra water for workouts especially when it is warm outside.
Staying hydrated? Try weighing yourself before and after practice just a couple times, and you will need to drink 2 cups of water for every pound lost.
Remember lemonade not apple juice