What's Up With Water?

by Kim Mueller, MS, RD, Sports Nutritionist

As the most abundant substance in the body, making up 80 percent of our total body weight, water plays a critical role in optimizing health and enhancing running performance. Helping to nourish our cells, lubricate our joints, optimize our metabolism and promote peak muscle function, water is considered an essential nutrient. Unfortunately, water is often the most neglected nutrient with many runners using thirst or other symptoms like fatigue, itchy skin, headaches, indigestion and constipation as markers for fluid intake. A recent survey of approximately 3,000 Americans discovered that 10 percent avoid water altogether, opting for such dehydrating beverages as caffeinated coffee and tea, soda or alcohol instead. The average American consumes only six eight-ounce servings of water a day, which, for many, falls short of the goal fluid intake-about 50 percent of your total body weight (in pounds) in fluid ounces.

Runners and walkers, who lose additional amounts via sweat as exercise, require additional amounts of water as compared to more sedentary people. In addition to drinking half their body weight in fluid ounces at rest, runners should consume 5-12 ounces of water every 15-20 minutes of a run lasting less than an hour (sports drinks should be consumed rather than plain water during runs lasting more than an hour).

However, runners do not often replace an adequate amount of fluid to avoid performance declines from dehydration. A recent study conducted on runners completing a 10-mile race found that they tended to underestimate their sweat losses by an average of 46 percent and their fluid intake by an average of 15 percent, resulting in the runners replacing only 30 percent of fluids lost through sweat. And a lack of fluid definitely adds up on the course. In fact, a mere two percent dehydration (equal to a loss of three pounds in a 150-pound runner) during a 10-mile race can cause a runner to slow down by as much as three-and-a-half minutes. Furthermore, dehydration inhibits recovery. Runners need to consume 16-24 ounces of fluid for every pound lost during a run. Dehydration becomes life-threatening when 10-20 percent of body weight is lost.

Fortunately, there is a multitude of types of water available on the market today to suit any palate and help you stay on top of your fluid game.

Plain Ol' Water in a Bottle
Plain ol' water comprises a third of the total fluid consumed by Americans today, with some 40 percent opting to drink bottled water over tap water. Why the preference? Some bottled water users claim that bottled water is "safer" than tap water, though stricter safety standards actually exist for tap water. Others believe that bottled water is "better for you." However, there is little scientific evidence indicating any nutritional benefit over your local water supply, which may also include small amounts of such beneficial minerals as calcium and magnesium. The majority of bottled-water drinkers actually choose to drink bottled water for its mere convenience. There are actually several different varieties of bottled water from which to choose.

Mineral Water
Distinguished from other types of bottled water by its constant level and relative proportions of mineral and trace elements at the point of emergence from the source. No minerals can be added to this product. Manufacturers claim that mineral water is very beneficial for the body.
Examples: Fiji, Sephora and King Milos.

Oxygenated Water
Oxygenated water uses a process that dramatically elevates the level of dissolved oxygen in the water. There's been a recent influx of oxygenated waters with the claim, "the body absorbs the extra oxygen, resulting in improved stamina and athletic performance, reduced recovery time and better mental clarity." While intriguing, a recent study coordinated by the American Council on Exercise found that drinking super oxygenated water had NO measurable effect on the subjects' resting heart rate, blood pressures or blood lactate values, indicating there was no performance benefits from the enhanced water as compared to tap water.
Examples: Aqua Rush, AquOForce and Athletic Super Water.

Purified Water
Purified water is produced by distillation, deionization, reverse osmosis or other suitable processes and meets the definition of purified water in the United States. It may contain added minerals such as calcium, magnesium and potassium. Penta-Hydrate is unique compared to some of the other purified waters on the market in that it is created through a seven-step process that removes impurities and chemicals as well as creating a smaller cluster of water molecules for enhanced water absorption. One study conducted at University of California San Diego demonstrated a 14 percent faster absorption rate with the Penta as compared to tap water.
Other examples: Aquafina, Dasani and Smartwater.

Sparkling Water
Water that, after treatment and possible replacement with carbon dioxide, contains the same amount of carbon dioxide that it had at emergence from the source. Sparkling water has a refreshing, crisp, clean taste.
Example: Calistoga.

Spring Water
Water derived from an underground formation from which water flows naturally to the surface of the earth. Spring water is a safe water, with a clear, clean taste no other drinking water can match.
Examples: Arrowhead, Deer Park, Evian, Ozarka and Poland.

Flavored and Enhanced Waters
A common excuse for not drinking enough water, whether it is tap or bottled water, is a dislike for the taste. These days, however, there is a multitude of flavored beverages designed to provide a tasty alternative to plain water while avoiding the calorie punch of such other flavored beverages as fruit juice and sodas. Also packed with vitamins, minerals and possibly some herbal supplements, flavored waters tend to make a wide variety of claims, including "rejuvenate, replenish and restore the body," "boost metabolism," "neutralize free radicals" and "enhance stamina and brain power." While these claims are intriguing, they are not necessarily backed by scientific research, which means drinking the beverage probably won't fulfill the claims made by the company. However, if you find it hard to palate plain water, flavored waters will offer some benefit to your hydration status.

Most flavored waters do not contain a significant amount of carbohydrate and electrolytes and therefore should not be used as your sole hydrating beverages during runs lasting greater than one hour.
Examples: Gatorade's Propel Fitness Water, Glaceau Vitamin Water, Reebok Fitness Water and Fruit20 Plus.

Drink Up!
Whether you choose to drink bottled water or tap water, both are guaranteed to provide you with the fluid you need for proper hydration both during the day as well as during runs lasting less than an hour. Aim at drinking half your body weight (in pounds) in fluid ounces on a daily basis plus an additional five to 12 ounces every 15 minutes during runs lasting less than an hour. For those who are bored with drinking plain water, use flavored waters to help promote proper hydration. Remember, though, that the vitamins and minerals in flavored waters most likely won't enhance your performance and health and should not replace the vitamins and minerals received from whole foods.

Whatever the water you choose, it is the quantity rather than type of beverage you consume that will dictate your running performance. And remember that although water is appropriate for runs lasting less than an hour, sports drinks are more desirable during longer runs due to the presence of carbohydrate for glycogen repletion and electrolytes for fluid absorption and optimal muscle function. Cheers!

About the Author: Kimberly J. Mueller, MS, RD is a Registered Sports Dietitian and competitive endurance athlete who provides nutritional counseling and meal planning to athletes all around the world. She can be reached at kjmuell@hotmail.com.