Summer Some other questions this desk reference can answer: How do sports drinks work? What should you look for in a sports drink?

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1 Summer 1998 In an effort to provide you with the latest research and information on sports drinks and hydration, we are pleased to present you with Fluids 2000, a desk reference designed to easily provide you with a comprehensive consolidation of the current information in the areas of fluids and hydration. The Gatorade Company has more than 30 years of experience in researching the physiology of thirst and the fluid needs of active individuals. The research has been conducted at various universities around the world as well as at our own Exercise Physiology Lab in Barrington, Ill. In fact, we re proud to say that Gatorade is the most thoroughly researched beverage in the world. No other sports drink has the scientific substantiation that Gatorade does and research consistently affirms that. Nothing works better than Gatorade at putting back fluids, electrolytes and energy -- not water, fruit juices, soft drinks or other sports drinks. In particular, we want to bring your attention to some new research findings that indicate you don t have to be an endurance athlete to benefit from sports drinks. Research now shows that a properly formulated sports drink is beneficial even for those exercising only an hour. That research is included in this binder. Some other questions this desk reference can answer: How do sports drinks work? What should you look for in a sports drink? What s the best beverage for active kids? How much and how often should active people drink? We encourage you to turn inside to find answers to these questions and a whole lot more. We also have provided a list of respected and well known sports science experts for you to contact for more information on sports nutrition topics. We invite you to use Fluids 2000 as a reference and we encourage you to speak with some of these sports science experts whenever you re writing about recreational sports, personal fitness, hot weather activities or sports nutrition. Thank you for your interest in the Science of Gatorade. Lisa Carlson, M.S., R.D. Manager of Sports Nutrition Education The Gatorade Company

2 Table of Contents Section Page(s) What Happens When You Get Hot & Sweaty? How the Body Loses Heat The Facts About Sweat What Are the Signs of Dehydration & Heat Illness? Warning Signs of Dehydration, Heat Exhaustion and Heat Stroke... 5 Heat Index - a temperature/humidity chart that assesses the potential risk of heat illness... 6 Tips to Beat Heat Illness... 7 How Do Sports Drinks Work? What To Look For in a Sports Drink How to Read a Sports Drink Label Fluid Comparison Chart - an ingredient comparison of sports drinks and other beverages How Sports Drinks Compare with Other Beverages Q&A on Sports Drinks How Do Sports Drinks Benefit Active Kids? Selecting Beverages for Active Kids Research Summaries and Articles on Fluids for Active Kids What are the Benefits of Sports Drinks Over Water? Sports Drinks vs. Water Research Summaries on Performance Benefits of Sports Drinks vs. Water How Much Should You Drink -- and When? Fluid Guidelines for Active People Fluid Pyramid - an easy to understand guide for how much people should drink based on activity levels New Research Indicates Sports Drinks are Beneficial Even for Exercise Lasting Less Than an Hour Key points from the American College of Sports Medicine Position Stand on Fluid Replacement... 35

3 Table of Contents Section Page(s) Where Do You Go For More Information? List of Sports Science Experts -- and their area of expertise Gatorade Exercise Physiology Laboratory - a state-of-the-art research facility staffed by sports science professionals who fully explore the role of fluid replacement and sports nutrition in athletic performance Gatorade Sports Science Institute - an educational resource institute that distributes non-commercial sports science information to sports health professionals and media throughout the world Gatorade Product Information Gatorade Performance Series Gatorade Thirst Quencher GatorLode High Carbohydrate Loading and Recovery Drink GatorPro Sports Nutrition Shake What s the Latest Research on Fluids and Performance? Research Summaries - a comprehensive list of research summaries on hydration and performance; copies of research are available on request Glossary of Sports Nutrition Terms What Are the Needs of Special Populations? Industrial Workers Diabetes Older People Asthma Spinal Cord Injuries Pregnancy

4 What Happens When You Get Hot & Sweaty? HOW THE BODY LOSES HEAT Key Points Exercise creates body heat. The evaporation of sweat is the primary way the body loses heat and regulates a safe body temperature. Thirst is not a good indicator of a person s fluid needs. By the time you re thirsty, you have already lost fluids and may be dehydrated. Fluids lost through sweat must be replaced to avoid dehydration, especially when exercising in warm weather. How Your Body Loses Heat: When exercising, your body temperature increases (from muscle contraction and metabolism). The main way to reduce body temperature is from sweating. When sweat evaporates from your body, heat is lost and so are body fluids. You need to replace those fluids to avoid dehydration and to maintain your performance. Heat may be lost from the body through: Radiation: Conduction: Convection: Evaporation: heat radiates from the body to cooler objects (i.e., buildings, walls, trees, earth and the air) heat is transferred from the body by direct physical contact (i.e., skin immersed in cool water; person swimming in cool water) heat is transferred by movement of cool currents of air or water over the body (i.e., riding a bicycle) heat is lost when sweat is converted to water vapor How Dehydration Affects Your Body: Dehydration results in premature fatigue and increases the risk of heat illness. Dehydration disturbs the body s fluid and electrolyte balance, harms the energy-producing processes in muscle cells, increases stress on the heart and contributes to the effects of excess body heat. Athletic or work performance can also be negatively affected by the sweat loss of as little as one percent of body weight due to dehydration, so proper hydration is critical. Fluids 2000 Provided by The Gatorade Company Page 1

5 What Happens When You Get Hot & Sweaty? HOW THE BODY LOSES HEAT How Dehydration Affects Your Body (cont.): In response to dehydration, the body triggers certain responses in an effort to return itself to its normal state of body-fluid content. These responses include stimulation of thirst, reduced urine output and conservation of sodium by the kidneys. Dehydration is cumulative. If lost fluids and minerals go unreplaced, fatigue and heat illness can result. In its most severe form, heat illness can lead to death. Why You Need to Replace Fluids: Dehydration is a serious potential problem for anyone. Children and older adults who are exposed to conditions where they become hot and sweaty are at greater risk. The only way to avoid dehydration when you re active is to drink plenty of fluids. And not just any fluid will do. A sports drink like Gatorade is scientifically formulated to promote rapid fluid absorption, provide carbohydrate energy to maintain performance, provide a taste that encourages voluntary fluid consumption and help maintain important physiological functions. Thirst alone is not a good indicator of the need for fluids. Typically people only replace 1/3 to 2/3 of their sweat loss. When exercising, it s important to drink early and often. Research demonstrates that exercise under warm or hot and humid conditions can cause dehydration in as little as 15 minutes. It is therefore important to consume fluids not only during and after exercise and activity, but also before a workout or strenuous activity. Don t wait until you re dehydrated to start drinking because drinking in a dehydrated state can cause gastrointestinal distress. Athletes who say they can t drink during a workout because it gives them a stomachache may be allowing themselves to become dehydrated before they take their first drink. They should drink before and during exercise to avoid these problems. The American College of Sports Medicine (ACSM) recommends that athletes drink enough fluid to fully replace sweat losses during activity. For optimal performance, active people should weigh themselves before and after exercising to determine how much fluid they are losing. At a minimum, people should ingest 8-10oz. of fluid every 15 min. during activity. It can take up to 24 hours after exercise to rehydrate -- if you only drink water. That s too long for most of us. Water alone is not an effective hydrator because it prematurely turns off thirst and turns on the kidneys before we ve had enough to drink. Our perception of thirst decreases with age. Older people therefore need to make an effort to drink more -- even if they aren t thirsty -- to avoid becoming dehydrated. Fluids 2000 Provided by The Gatorade Company Page 2

6 What Happens When You Get Hot & Sweaty? THE FACTS ABOUT SWEAT It s cool to sweat -- literally. Sweating is your body s most effective way of cooling itself because when sweat evaporates from your skin, body heat is reduced. While sweating is important, if you don t replace the fluids you lose through sweat, it can lead to dehydration and heat illness. That s why fluid replacement before, during and after exercise and activity is so crucial. What Happens When We Sweat During exercise, the heat produced by working muscles exceeds the heat released by the body, and body temperature rises. The rise in body temperature causes an increase in sweating and blood flow to the skin. As a result heat is removed by the evaporation of sweat from the skin, radiated from the body to the cooler surroundings, and is lost by convection to moving air. Our bodies are approximately 55-65% fluid. When some of that fluid is lost through sweat, it affects our cardiovascular system and our ability to control temperature. Factors that Influence Sweat Rates: Environment - High temperatures cause you to sweat more quickly and to lose more fluids through sweat. Humidity also affects your ability to cool off. It s harder for sweat to evaporate in hot, humid weather than in hot, dry weather (see Heat Index chart, pg. 6). Exercise intensity - As your body works harder, body temperature increases, which leads to greater sweat loss. Clothing and equipment - Minimal, loose-fitting clothing helps promote heat loss. Heavy clothing and equipment (e.g., football uniform and helmet) doesn t allow heat to be released as easily and increases sweating. Genetics - Heredity has some effect on your ability to sweat, but being in good physical condition is usually a more important factor. Fitness and acclimatization - As you increase your fitness, you become a better sweater. You sweat sooner and you sweat more. The body adapts to exercise in warmer temperatures by sweating more. Fluids 2000 Provided by The Gatorade Company Page 3

7 What Happens When You Get Hot & Sweaty? THE FACTS ABOUT SWEAT Sweat Glands The body has approximately 2-4 million sweat glands weighing a total of approximately 100 grams (about 3 ounces). The most concentrated area of sweat glands is on the bottom of our feet while the least concentrated area of sweat glands is on our back. Women have more sweat glands than men, but men s are more active. Fluids 2000 Provided by The Gatorade Company Page 4

8 What Are The Signs of Dehydration & Heat Illness? WARNING SIGNS OF DEHYDRATION, HEAT EXHAUSTION AND HEAT STROKE Dehydration If You Feel Like This......Do This Loss of Energy & Performance Choose sports drinks. Drink fluids with carbohydrate to prevent fatigue and provide energy. Small amounts of sodium promote rehydration. Avoid beverages containing caffeine or carbonation. The caffeine can cause further dehydration and carbonation can cause stomach upset. Muscle Cramps Stop activity and massage cramped muscles. Choosing a sports drink that contains the right amount of sodium (at lest 100mg/8oz) may relieve and prevent muscle cramps. Heat Exhaustion If You Feel Like This......Do This Dizziness, Lightheadedness and Cold, Clammy Skin Replace fluids. Rehydration is critical. Rest in a cool, shaded area until dizziness passes. Stretching may improve circulation and prevent fainting. If dizziness continues, lying with the legs elevated will promote circulation to the head. Nausea/Headaches Rest in a cool place until nausea passes. Rehydration is critical; drinking fluids is a must. Lying down is often helpful in relieving headaches. Heat Stroke If You Feel Like This......Do This High Body Temperature and Dry Skin Get out of heat and seek immediate medical treatment. Feeling chilly, with arms tingling and goosebumps, means skin circulation has shut down and heat stroke is imminent. Confusion or Unconsciousness Confusion strongly suggests -- and unconsciousness basically means -- heat stroke. Heat stroke is an emergency that calls for fast cooling with ice baths or any other available means. Fluids 2000 Provided by The Gatorade Company Page 5

9 What Are The Signs of Dehydration & Heat Illness? TIPS TO BEAT THE HEAT (ILLNESS) Allow for acclimatization (adaptation) in hot seasons. Cut back on exercise intensity and duration in hot weather. Slowly build back to previous level over the next 10 days. Drink up when it s hot. Once acclimatized, sweat losses will be higher, so fluid intake has to be greater. Don t be overly competitive under hot conditions. Try for a personal best on a cooler day. Don t just pour water over your head. It may feel great, but it won t help at all at restoring body fluids or lowering body temperature. Fluid has to go in the body. Carry sports drinks, like Gatorade, with you if you know they will not be available at the exercise site. Bottle belts are great for this. Also carry money to buy something to drink. Select lightly flavored, sweetened beverages containing sodium. Sodium has been scientifically proven to encourage voluntary drinking and promote hydration. Exercise in the morning or evening when the weather is coolest. Avoid the sun s rays to minimize the radiant heat load. Wear light-colored, light-weight porous clothing. Do not change into a dry shirt at breaks or time-outs. Completely soaked shirts do better at cooling the body. Fluids 2000 Provided by The Gatorade Company Page 6

10 How Do Sports Drinks Work? WHAT TO LOOK FOR IN A SPORTS DRINK Key Points Sports drinks are designed to promote rapid fluid replacement and enhance performance. The optimum sports drink is non-carbonated, non-caffeinated, contains 6% carbohydrate (14g/8oz), a small amount of sodium, and tastes good when you re hot and thirsty. Not all sports drinks are created equal: read the label. Sports drinks are formulated to taste best when you re hot and sweaty. Research shows that people will stay better hydrated when a beverage is lightly flavored to encourage more drinking Here s What To Look For in a Sports Drink: The right amount of carbohydrate -- 14g per 8oz or 6% carbohydrate The right mix of carbohydrates -- a combination of sucrose, glucose and fructose The right amount of sodium -- at least 100mg per 8oz Lightly sweetened, lightly flavored -- the taste people prefer when they re hot and thirsty No carbonation, no caffeine See the following page for a list of sports drink ingredients and their functions. Fluids 2000 Provided by The Gatorade Company Page 7

11 How Do Sports Drinks Work? WHAT TO LOOK FOR IN A SPORTS DRINK Ingredients and their Function Carbohydrates Water Electrolytes: Sodium and Potassium Flavor Carbohydrates Carbohydrates are an important ingredient in sports drinks because they supply energy for working muscles. They also improve beverage taste and are essential to stimulate fluid absorption by the small intestine and enhance athletic performance. Plain water does not contain carbohydrates and therefore does not provide energy. The three main types of carbohydrates used in sports drinks are sucrose, glucose and fructose. Research has shown a combination of sucrose, glucose and fructose to be very effective at speeding energy to muscles. However, fructose is slower at getting into the system and can cause digestive problems if it s the only carbohydrate in the beverage (e.g., fruit juice). A common source of glucose and fructose is glucose syrup solids (also known as high fructose corn syrup, derived from corn). Sports drinks containing only fructose are less effective. Striking the correct carbohydrate balance in a beverage is key to its effectiveness. Research has shown that a 6-percent carbohydrate solution (14g/8oz.) provides enough sweetness to encourage fluid consumption, supplies ample energy to working muscles, stimulates rapid fluid absorption and helps enhance performance. Water The body is made up of 55 to 65 percent water and relies on a proper fluid balance to assure optimal functioning of the heart and maintenance of body temperature. Losing as little as one percent of body weight due to sweat loss can adversely affect body functions. Carbohydrates and electrolytes carry water through the small intestine and into the bloodstream. Carbonated beverages release their carbonation (carbon dioxide gas) in the stomach, increasing the risk of gastrointestinal distress (bloating, stomachache and nausea). Fluids 2000 Provided by The Gatorade Company Page 8

12 How Do Sports Drinks Work? WHAT TO LOOK FOR IN A SPORTS DRINK Ingredients and their Function (cont.) Electrolytes Electrolytes (minerals such as sodium) are essential to help in rehydration by promoting fluid absorption in the small intestine. Consuming a beverage that does not contain sodium -- water, for example -- will satisfy thirst before rehydration is complete. It s actually the level of sodium in the bloodstream that makes the body thirsty, and sodium is used in sports drinks because it helps ensure that you drink until fully rehydrated. It doesn t take a lot of sodium to make a sports drink work. For example, Gatorade contains enough sodium for optimal rehydration and is actually considered low in sodium by FDA standards, containing about the same amount of sodium in a serving of milk or a slice of bread. While sodium lost during an hour of exercise can be replaced with a balanced diet, rapid and complete rehydration depends on ingesting both fluid and sodium. Potassium, another electrolyte lost through sweat, is involved in muscle and nerve contraction, and kidney function. Sports drinks should be formulated to replace the small amount of potassium that s lost through sweat. Flavor Research shows that people prefer a beverage that is lightly sweetened and lightly flavored when they exercise or get hot and thirsty. The carbohydrate, sodium and flavoring in sports drinks all encourage fluid consumption and complete rehydration. Fluids 2000 Provided by The Gatorade Company Page 9

13 How Do Sports Drinks Work? HOW TO READ A SPORTS DRINK LABEL Key Points Look for sports drinks with 14g/8oz of carbohydrate to encourage rapid fluid replenishment (this is a 6% carbohydrate concentration). Research shows that Gatorade is absorbed as fast as water. Each ingredient in a sports drink (carbohydrate, water, sodium and potassium) performs an important function. Reading A Sports Drink Label Carbohydrates, sodium, electrolytes and flavoring -- what is all this stuff, what does it do for you? How much do you need for optimal fluid replenishment? The answers are on the label. The label on Gatorade shows 14 grams of carbohydrate per 8-ounce serving, but what s the carbohydrate concentration? With a little math you can see it s an ideal 6 percent. A sodium level of about mg per 8 oz enhances the taste, optimizes absorption, and maintains body fluids. Diluted juices are severely lacking in this area. Generally speaking, the lower sodium levels in water and some sports drinks (e.g., Powerade and AllSport) may not stimulate voluntary drinking or help maintain fluid balance as does the higher sodium content in other sports drinks. Research shows that the 6% concentration of carbohydrate in Gatorade (14g/8 oz) is optimal for rapid fluid replacement and improved performance. Recent studies show that Gatorade is absorbed faster than sports drinks, like Powerade and AllSport, with carbohydrate concentrations of 8% or more. (Gatorade is absorbed as fast or faster than water. Water has no carbohydrate and therefore provides no energy) Gatorade (Lemon-Lime flavor) Nutrition Facts Serving size 8 fl oz (240ml) Serving Per Container 2 Amount Per Serving Calories 50 % Daily Value* Total Fat 0g 0% Sodium 110mg 5% Potassium 30mg 1% Total Carbohydrate 14g 5% Protein Sugars 14 g 0g Not a significant source of Calories From Fat, Saturated Fat, Cholesterol, Dietary Fiber, Vitamin A, Vitamin C, Calcium, Iron *Percent Daily Values are based on a 2,000 calorie diet. INGREDIENTS: WATER, SUCROSE SYRUP, GLUCOSE SYRUP, GLUCOSE-FRUCTOSE SYRUP, CITRIC ACID, NATURAL LEMON AND LIME FLAVORS WITH OTHER NATURAL FLAVORS, SALT, SODIUM CITRATE, MONOPOTASSIUM PHOSPHATE, ESTER GUM, YELLOW 5. The level of potassium (25mg/8 oz) as well as the sodium level should attempt to replace body losses in proportion to those levels lost in sweat. Don t confuse the % daily value with the carbohydrate percentage of a beverage. Vitamins and Sports Drinks: No data exist to show a physiological benefit of adding any vitamins to a sports drink. In fact, some B vitamins adversely affect the taste of a beverage and could discourage adequate fluid intake. The type of carbohydrate (as well as the %) affects sweetness and can reduce fluid intake if too sweet. High fructose levels can cause gastrointestinal distress because they slow absorption. Multiple carbohydrate sources, such as the sucrose and glucose and less fructose, help stimulate fluid absorption. Calculate the carbohydrate % of any beverage: To in equals one calculate serving 240 milliliters). the (in carbohydrate grams) by the concentration amount of fluid of any in one beverage serving as (in a percentage, milliliters), and divide then the multiply amount by of 100 carbohydrate (8 ounces For Gatorade: 14 grams carbohydrate x 100 = 5.83 or 6 percent carbohydrate concentration 240 milliliters Fluids 2000 Provided by The Gatorade Company Page 10

14 How Do Sports Drinks Work? FLUID COMPARISON CHART Ingredient/ Composition Per 8 oz. Gatorade Powerade AllSport Orange Juice Water Type of Carbohydrate Sucrose, Glucose, Fructose Fructose, Glucose Polymers, Maltodextrins High Fructose Corn Syrup Glucose, Fructose, Sucrose Here s What To Look For Per 8 oz. 0 Sucrose, Glucose, Fructose Mix of carbohydrates Carbohydrate Content (%) 6% 8% 8-9% 10% 0% 6% Carbohydrate Carbohydrate (grams) Osmolality (mosm) Sodium (milligrams) Potassium (milligrams) Carbonation 14g 19g 19g 26g 0g About 14g Carbohydrate Approximately 300 Osmolality At Least 100 mg At Least 28 mg. 0 0 Carbonated 0 0 No Carbonation Note: Vitamins and Sports Drinks: No data exist to show a physiological benefit of adding any vitamins to a sports drink. In fact, some B vitamins diminish the taste of a beverage and could discourage adequate fluid intake. Commentary The type of carbohydrate (as well as the %) affects sweetness and can reduce fluid intake if too sweet. High fructose levels can cause gastrointestinal distress because they slow absorption. Multiple carbohydrate sources, such as the sucrose, glucose and fructose, help stimulate fluid absorption. Research shows that the 6% concentration of carbohydrate in Gatorade (14g/8 oz) is optimal for rapid fluid replacement and improved performance. Recent studies show that Gatorade is absorbed faster than sports drinks, like Powerade and AllSport, with carbohydrate concentration of 8% or more. (Gatorade is absorbed as fast or faster than water.) Osmolality is a term referring to the number of particles in a solution. A solution with fewer particles (low osmolality) tends to produce faster absorption of fluid. High osmolality (>400) can slow fluid absorption. A sodium level of about mg per 8 oz enhances the taste, optimizes absorption, and maintains body fluids. Diluted juices are severely lacking in this area. Generally speaking, the lower sodium levels in some sports drinks (e.g., Powerade and AllSport) may not stimulate voluntary drinking or help maintain fluid balance as does the higher sodium content in other sports drinks. The level of potassium (25mg/8 oz) as well as the sodium level should attempt to replace body losses in proportion to those levels lost in sweat. Carbonation discourages fluid intake due to gastric bloating, and throat burn. Even low levels of carbonation lead to inadequate fluid intake, which contributes to dehydration. Fluids 2000 Provided by The Gatorade Company Page 11

15 How Do Sports Drinks Work? HOW SPORTS DRINKS COMPARE WITH OTHER BEVERAGES Key Points Properly formulated sports drinks (6% carbohydrate or 14g/8oz) are more rapidly absorbed and are more effective at replacing fluids than water, soft drinks or juice. Carbonated and caffeinated beverages and those high in carbohydrate should be avoided during exercise. Research shows drinking a sports drink during endurance and stop-and-go sports can supply energy to working muscles and help improve performance. Absorption: Sports Drinks vs. Other Beverages Plain water is often not enough for proper hydration. An accumulation of research shows that sports drinks are better for maintaining hydration than drinking water alone. Water turns off thirst before complete rehydration occurs. In fact, research shows that people will drink more of a lightly flavored beverage than plain water and therefore will stay better hydrated. Water also turns on the kidneys prematurely so you lose fluid in the form of urine much more quickly. The small amount of sodium in a sports drink like Gatorade -- no more than what is in an equal size glass of milk -- allows your body to hold onto the fluid you consume rather than losing it through urine. Carbonated and sweetened soft drinks (e.g. Coke and Pepsi) contain carbohydrates at a concentration of 10 to 11 percent. Compared to Gatorade (6% carbohydrate solution), such beverages are absorbed slowly. In addition, the carbonation turns into carbon dioxide gas in the stomach and can cause gastrointestinal distress. The caffeine found in many soft drinks actually increases fluid loss by stimulating urine production. Fruit juice is not an ideal fluid-replacement beverage for exercise because of its high carbohydrate and low sodium content. Once again, beverages with too much carbohydrate, like fruit juices, are absorbed more slowly and may cause stomach discomfort. Even when fruit juices are diluted they don t contain enough sodium to stimulate voluntary drinking or help maintain fluid balance. Properly formulated sports beverages contain about 6 percent carbohydrate (14g/8oz). Research shows the 6-percent carbohydrate concentration in Gatorade is absorbed as fast as water. This formulation also provides energy to the muscles. Water provides no energy. Fluids 2000 Provided by The Gatorade Company Page 12

16 How Do Sports Drinks Work? HOW SPORTS DRINKS COMPARE WITH OTHER BEVERAGES What Carbohydrates Do For You: During exercise, the body increases its use of carbohydrate energy. Low carbohydrate stores can affect performance and speed up the onset of fatigue. The carbohydrates in properly formulated sports drinks can help increase exercise duration by supplying energy to the muscles. Research now demonstrates that consuming carbohydrates can improve performance even during high-intensity exercise lasting less than an hour. Rehydration: What Goes On In Your Body? The small intestine is well designed for fluid and nutrient absorption. Once absorbed, fluids and nutrients are circulated by the bloodstream to the body s muscles and organs. The speed at which a beverage travels from the stomach into the small intestine (the gastric emptying rate) depends on the energy content (calories) and volume (amount) of beverage consumed. A low concentration of carbohydrate will encourage rapid absorption. But too much carbohydrate will slow gastric emptying and can result in gastrointestinal distress. Glucose and sodium have been shown to enhance fluid absorption in the small intestine. Beverages with fructose as the sole source of carbohydrate have been reported to cause gastrointestinal distress because fructose is absorbed too slowly. Properly formulated sports beverages are the only fluids for complete and fast rehydration following exercise. Fluids 2000 Provided by The Gatorade Company Page 13

17 How Do Sports Drinks Work? Q&A ON SPORTS DRINKS Q What is a sports drink? A A sports drink refers to a beverage that is formulated for quick replacement of fluids and electrolytes lost during exercise, and that provides carbohydrate fuel to working muscles. Fluid replacement helps prevent dehydration from sweat, while carbohydrates enhance exercise performance. Q What is better for rehydration and performance -- water or a sports drink like Gatorade? A Sports drinks are formulated to be even more effective than water for occasions when fluid, carbohydrate and electrolyte replacement is needed, such as an intense workout class or a game of basketball. In fact, there are many occasions when Gatorade is more effective than water, but no occasion when water is more effective than Gatorade. Although a cool drink of water feels satisfying, water turns off your thirst before complete rehydration occurs. Water also turns on the kidneys prematurely so you lose fluid in the form of urine much more quickly than when drinking a properly formulated sports drink. This is because the small amount of sodium in a sports drink like Gatorade - - no more than what is in an equal size glass of milk -- allows your body to hold onto the fluid you consume rather than losing it through urine. A properly formulated sports drink should contain an optimum amount of carbohydrates (14 g. carbohydrate/8 oz.), electrolytes (sodium and potassium) and water. Plain water will not replace the electrolytes that the body loses through sweat, nor will it provide energy. A sports drink does both. Q Is a sports drink just for exercise lasting more than an hour? A No. A sports drink like Gatorade is an appropriate fluid replacement beverage for all exercise occasions. Someone who exercises, even in small amounts, can benefit from the rapid fluid replacement a sports drink provides. Research shows that, during exercise people prefer the taste of a lightly flavored sports drink compared to other alternatives, such as plain water. Research also shows that if a person likes the taste they will drink more to stay better hydrated. Also, recent research from Mark Davis, Ph.D., at the University of South Carolina, indicates that sports drinks provide performance benefits even for intense exercise lasting less than an hour. It s really the intensity of exercise and the duration that matter. Fluids 2000 Provided by The Gatorade Company Page 14

18 How Do Sports Drinks Work? Q&A ON SPORTS DRINKS Q How does Gatorade compare to Powerade or AllSport? Are all sports drinks the same? (Refer to page 12 for nutritional information for Powerade and AllSport) A Not all sports drinks are created equal. Here s what to look for in a properly formulated sports drink: Tastes great when you re hot and thirsty -- this encourages people to drink more. The right carbohydrate level -- 6% solution (14 g. / 8 oz.). More carbohydrate in a sports drink (like AllSport and Powerade which have at least 8% carbohydrate) is not better and doesn t provide additional performance benefits -- just extra sugar and calories. The extra carbohydrate can also cause an upset stomach. A blend of several carbohydrates -- for fast absorption and optimal sweetness during activity. Sports drinks with mostly fructose may slow absorption and cause stomach cramps. Contains electrolytes -- sodium and potassium when combined with glucose help restore fluid balance. Drinks with less than 100 mg. of sodium per 8 oz. (like AllSport and Powerade) may not be as effective in speeding rehydration. No carbonation -- the fizz can cause throat burn, gastric discomfort and reduced consumption. Even a small amount of carbonation, like that in AllSport, is not recommended during exercise. Q Who should consume a sports drink? A Everyone and anyone. Sports drinks are specifically formulated to benefit physically active people and anyone who works up a sweat -- from active kids to athletes to occupational workers. A properly formulated sports drink is lightly flavored and lightly sweetened and is designed to taste best during active occasions. Also, recent research from Mark Davis, Ph.D., at the University of South Carolina, indicates that sports drinks provide performance benefits even for intense exercise lasting less than an hour. It s really the intensity of exercise and the duration that matter. Fluids 2000 Provided by The Gatorade Company Page 15

19 How Do Sports Drinks Work? Q&A ON SPORTS DRINKS Q What is it in Gatorade that quenches your thirst? A Gatorade quenches thirst through a unique carbohydrate-electrolyte solution [14 grams (g) carbohydrate, 110 milligrams (mg) sodium per 8 ounces (oz)]. Unlike drinking plain water, Gatorade quenches deep down body thirst by: A) Encouraging voluntary fluid consumption when people are hot and thirsty. Gatorade is considerably less sweet than soft drinks or fruit juices, a characteristic that is more appealing to people in hot and sweaty conditions. Gatorade contains a small amount of sodium that encourages people to drink beyond the point at which mouth thirst is satisfied, helping assure rapid rehydration. B) Stimulating rapid fluid absorption. The unique formulation of Gatorade allows it to empty from the stomach as fast as water. Once in the small intestine, Gatorade s combination of sodium and glucose stimulates rapid absorption across the intestinal wall into the bloodstream. C) Maintaining important physiological responses. Drinking Gatorade can help you avoid dehydration and other heat-related problems such as heat cramps, lightheadedness or fainting, heat exhaustion, or heat stroke. D) Supplying carbohydrate energy to active muscles. The 6% carbohydrate solution in Gatorade (14 g. per 8 oz.) not only provides the optimal formulation to assure fast rehydration, but speeds energy in the form of carbohydrate to working muscles, which helps to enhance physical performance. E) Assuring rapid and complete rehydration. The Gatorade formulation helps the body to absorb fluid quickly, and retain fluids longer than when drinking water alone, causing more complete rehydration. Sodium is important in this regard. Fluids 2000 Provided by The Gatorade Company Page 16

20 How Do Sports Drinks Work? Q&A ON SPORTS DRINKS Q Is Gatorade appropriate for children and infants? A Any child who can drink fruit juice, milk, soft drinks, and similar beverages can drink Gatorade. In fact, scientific research shows that physically active children will drink more Gatorade than water and therefore stay better hydrated. (Adults can also benefit in a similar fashion.) Gatorade provides about half the calories of an identical serving size of fruit juice or soft drink. By U.S. FDA standards, an 8oz serving of Gatorade is a low-sodium food. Gatorade has 110mg of sodium, the same as an 8oz glass of milk or once slice of bread. Infants: Gatorade does not pose any risk to infants; however, because an infant s fluid needs are normally met by drinking breast milk or formula, consumption of beverages other than formula or breast milk may deprive infants of additional necessary nutrients (e.g., fat, protein and vitamins). Children who are ill: Pediatricians often recommend Gatorade for children who are suffering from mild dehydration due to diarrhea or the flu. However, as is the case with any illness, it is best to consult a pediatrician to determine a child s needs. Q How does a homemade sports drink or diluted fruit juice compare to a commercial sports drink? A It s difficult to match the quality of a commercial sports drink in terms of flavor, shelf life and the combination of carbohydrates, electrolytes and fluids. One of the reasons a sports drink is so effective in hydrating active people is because it is formulated to turn on thirst. Preliminary research shows that diluted fruit juice or a homemade sports drink do not have the appeal of a commercial sports drink. As a result, people will drink less fluid than they need. Q Are sports drinks high in sugar? A No. A properly formulated sports drink like Gatorade contains only half the sugar and calories of many other beverage choices, including fruit juices and regular soft drinks. The carbohydrate in sports drinks is essential for providing energy to working muscles. However, some sports drinks (Powerade and AllSport) have 33% more sugar than Gatorade. This doesn t provide any additional benefits -- just additional calories. Fluids 2000 Provided by The Gatorade Company Page 17

21 How Do Sports Drinks Work? Q&A ON SPORTS DRINKS Q Are sports drinks high in sodium? A No. The small amount of sodium in sports drinks plays an important role in rehydrating your body. Gatorade has less sodium than a glass of milk or a slice of bread and is considered a low sodium food by FDA standards. Q Can people with diabetes drink Gatorade? A Yes. Gatorade can be consumed by diabetics with the same precautions that normally apply to the consumption of any food or drink containing carbohydrates. Gatorade can be particularly helpful for physically active diabetics who must consume a source of carbohydrate during exercise. An eight-ounce serving of Gatorade contains 14 grams of carbohydrate [8 oz (240 ml) and has approximately the same carbohydrate content as 4 oz (120 ml) of fruit juice]. Gatorade can provide a readily absorbable source of carbohydrate to help diabetics maintain their blood sugar level during exercise. In addition, the rapid fluid replacement that Gatorade provides can help diabetics stay well hydrated. However a physician or dietitian should always be consulted to confirm what is best for the individual. Q Should sports drinks be diluted? A No. A sports drink like Gatorade is formulated to provide the greatest benefits when it is consumed without dilution - at a 6% carbohydrate level (14g/8oz). Diluting Gatorade will not provide the performance benefits of full-strength Gatorade. However, some sports drinks with higher levels of carbohydrate (AllSport and Powerade) could be diluted, but they would still be too low in sodium. Fluids 2000 Provided by The Gatorade Company Page 18

22 How Do Sports Drinks Benefit Active Kids? SELECTING BEVERAGES FOR ACTIVE KIDS The Fluids In Your Fridge Matter to Kids When your child opens the refrigerator door or surveys the supermarket shelf to grab a drink to tote to soccer practice or for an afternoon of rollerblading or biking, what choices does he/she have? The beverages that parents put in the fridge matter, especially when rehydrating active children. By the time most active children become thirsty, they have lost important fluids and electrolytes (sodium and potassium), and may already be dehydrated. So it s important to think about the most suitable beverages for active children before they drink. How Much Do You Know About H20? Water is an OK beverage, especially when nothing else is available. However, water has its limitations. It does not provide energy, which may be needed if a child is running and playing all day. Children will also stop drinking water before their fluid needs are met. Often this is because water lacks the taste appeal of a lightly flavored beverage. If given a choice, kids will drink much more of a flavored beverage than of a glass of water. As a result, recent studies have shown that if given water, kids may not drink enough to prevent dehydration. Know The Score About Sports Drinks A properly formulated sports drink is a good choice for active children --whether it s for big brother after a soccer game or for little sister after playing in the yard all day -- because it supplies energy and electrolytes that encourage them to drink by turning on their thirst. Recently published research by Oded Bar-Or, M.D., a Professor of Pediatrics at McMaster University, indicates that during exercise, children stayed better hydrated when they drank a sports drink compared to drinking plain or flavored water. The reason: children voluntarily drank more of the sports drink, which contained carbohydrate and sodium. Ruth Carey, R.D., sports nutritionist and youth soccer coach, adds, I ve spent a lot of time on the sidelines of soccer games and parents, knowing my sports nutrition background, often ask my opinion on what kids should drink before, during and after activity. I tell them water is fine, but that I prefer to give my kids a flavored sports drink like Gatorade because they drink more and stay better hydrated. Fluids 2000 Provided by The Gatorade Company Page 19

23 How Do Sports Drinks Benefit Active Kids? SELECTING BEVERAGES FOR ACTIVE KIDS The Fluids In Your Fridge Matter to Kids Know The Score About Sports Drinks (cont.) Somewhat surprising, sports drinks only contain half the sugar and calories of many other beverage choices, including fruit juices and regular soft drinks. Sports drinks also have less sodium than a glass of milk or a slice of bread. The Juicy Story Fruit juices are typically fine for children after the playing is over. They often contain important vitamins. However, juice isn t always the best choice when rehydrating an active child before or during activity. The high sugar content in juice can slow fluid absorption and increase the chance of a stomachache. No kid wants to be side-lined because of a stomachache in the middle of his soccer game. Carbonation: Forget the Fizz Carbonated soft drinks, which are also high in sugar, are not appropriate during or after prolonged activity. The fizz in a carbonated beverage may cause a burning sensation in the mouth and may prevent your child from chugging enough fluids. Research shows that even a small amount of carbonation can also upset the stomach and cause a bloated feeling during exercise. To Keep Kids Cooled & Fueled Throughout the Summer Months, Follow These Helpful Tips: To help protect your children from the heat and dehydration, encourage them to drink fluids before, during and after sports and activities. Whether it s extremely hot or not, have your children drink on a schedule (approximately every 15 to 20 minutes during physical activity), because dehydration begins before they re thirsty. Make drinking fun by giving your child a squeeze bottle filled with a chilled beverage. To keep beverages chilled for game day or other outside activity: freeze half of the fluid in the squeeze bottle the day before the game, then add the rest of the fluid on game day. Fluids 2000 Provided by The Gatorade Company Page 20

24 What Are The Benefits of Sports Drinks Over Water? SPORTS DRINKS VS. WATER Sports drinks are formulated to be even more effective than water for occasions when fluid, carbohydrate and electrolyte replacement is needed, such as an intense workout, a game of basketball or an hour of rollerblading. In fact, there are many occasions when Gatorade is more effective than water, but no occasion when water is more effective than Gatorade. INGREDIENTS BEVERAGES Sports Drink (Gatorade) Water Carbohydrate Flavor Electrolytes: Sodium and Potassium Contains carbohydrate (14g./8oz.) to provide energy to working muscles. Carbohydrate content helps enhance performance. Sports drinks with a carbohydrate content of 6% are absorbed by the body as quickly as water. Has light flavoring which encourages people to drink more and therefore stay better hydrated; quenches body thirst Contains a small amount of sodium (110mg./8oz.) which increases the physiological drive to drink and allows active people to keep fluid in their system rather than losing it through urination Replaces electrolytes (sodium and potassium) lost in sweat Provides no energy to enhance performance Quenches mouth thirst quickly, but it turns off thirst before complete rehydration occurs Contains no sodium so water turns on the kidneys prematurely leading to the loss of fluid in the form of urine much more quickly than when drinking a properly formulated sports drink Does not replace electrolytes Fluids 2000 Provided by The Gatorade Company Page 21

25 What Are The Benefits of Sports Drinks Over Water? PERFORMANCE DURING HIGH-INTENSITY, INTERMITTENT EXERCISE: EFFECTS OF FLUID AND CARBOHYDRATE INTAKE The performance benefits of drinking carbohydrate-electrolyte beverages ( sports drinks ) during prolonged exercise (greater than one hour) are well established and the evidence of similar effects during shorter-duration and intermittent exercise is just beginning to accumulate. As noted in the American College of Sports Medicine position stand on Exercise and Fluid Replacement, preliminary results do indicate that proper carbohydrate nutrition (as the predominant energy source in the diet or consumed during exercise) can result in improved performance during exercise lasting less than one hour. Similarly, maintaining hydration has also been shown to improve high-intensity exercise performance of relatively short duration. This annotated bibliography highlights the results of some of the research in this area. Akermark, C., I. Jacobs, M. Rasmusson, and J. Karlsson. Diet and muscle glycogen concentration in relation to physical performance in Swedish elite ice hockey players. International Journal of Sports Nutrition. 6: , Swedish hockey players ingesting a high-carbohydrate diet improved their performance compared to players on a mixed diet. Performance measures included distance skated, number of shifts skated, time per shift, and skating speed. Results demonstrate that carbohydrate is an important fuel for athletes who participate in high-intensity intermittent sports. Anantaraman, R., A.A. Carmines, G.A. Gaesser, and A. Weltman. Effects of carbohydrate supplementation on performance during 1 h of high-intensity exercise. International Journal of Sports Nutrition. 16: , Subjects exercised for 60 min at 90% VO 2max under three conditions: 1) Carbohydrate before/placebo during exercise, 2) Carbohydrate before and during exercise, and 3) Placebo before and during exercise. Performance (maintenance of power output) was improved with Carbohydrate/Placebo trial compared to Placebo/Placebo, with Carbohydrate/Carbohydrate falling in between. Ball, T.C., S.A. Headley, P.M. Vanderburgh, and J.C. Smith. Periodic carbohydrate replacement during 50 min of high-intensity cycling improves subsequent sprint performance. International Journal of Sports Nutrition. 5: , When subjects ingested a 7% carbohydrate-electrolyte beverage during 50 min of cycling exercise they were able to perform better on a high-intensity performance task (Wingate test) compared to when they ingested a water placebo. Fluids 2000 Provided by The Gatorade Company Page 22

26 What Are The Benefits of Sports Drinks Over Water? PERFORMANCE DURING HIGH-INTENSITY... (CONT.) Below, P.R., R. Mora-Rodriguez, J. Gonzalez-Alonso, and E.F. Coyle. Fluid and carbohydrate ingestion independently improve performance during 1 h of intense exercise. Medicine and Science in Sports and Exercise. 27: , This study demonstrated that the performance benefits of preventing dehydration and ingesting carbohydrate are additive. Subjects cycled for 50 min at 80% VO 2max before completing a sprint to the finish(~10-12 min). Preventing dehydration by ingesting water improved performance by 6%, preventing dehydration and ingesting carbohydrate (with Gatorade) improved performance by 12%. Burke, ER and B Ekblom. Influence of fluid ingestion and dehydration on precision and endurance performance in tennis. In Current Topics in Sports Medicine: Proceedings of the World Congress of Sports Medicine. N Bachl, L Prokop, R Suckert (ed.s) Wien: Urban & Schwarzeberg, 1984, pp Active tennis players maintained skill performance throughout play when consuming fluids with carbohydrate compared to consuming no fluids or only water. Explosive power in vertical jump was higher after carbohydrate vs. water or no fluid. Also, fewer net shots and more total points awarded occurred with the carbohydrate trial. Improvements may be due to better maintenance of hydration or blood sugar levels with fluids containing carbohydrate. Davis, J.M., D.A. Jackson, M.S. Broadwell, J.L. Query, and C.L. Lambert. Carbohydrate drinks delay fatigue during intermittent, high-intensity cycling in active men and women. International Journal of Sports Nutrition 7: , Subjects exercised at % VO 2max for one minute, rested for 3 min, and repeated this procedure until exhaustion under two conditions: 1)Placebo before and during exercise, and 2) GatorLode before and Gatorade during exercise. Carbohydrate ingestion delayed fatigue, illustrating the performance-enhancing effect of carbohydrate feeding during high-intensity intermittent exercise similar to the demands of soccer, basketball, ice hockey, and other sports. Of special note is the fact that total exercise time was less than 30 min. Kirkendall, D., C. Foster, J. Dean, J. Grogan, and N. Thompson. Effect of glucose polymer supplementation on performance of soccer players. In: T. Reilly, A. Lees, K. David, and W. Murphy (Ed), Science and Football, pp E. and F.N. Spon, London, Soccer players covered 25% more distance during a game when a carbohydrate solution was ingested at half-time. Fluids 2000 Provided by The Gatorade Company Page 23