Fuel Your Workout with Sports Drinks
This is an adapted report written by Asker Jeukendrup, Ph.D., University of Birmingham, United Kingdom. His summary regarding carbohydrate ingestion during exercise is followed by comments from Amanda Carlson-Phillips, director of performance nutrition for Athletes' Performance. The complete document, including recommendations for specific events and physical activities can be found on the Gatorade Sports Science Exchange website at GSSIWeb.com.
Benefits of Sports Drinks
The benefits of consuming carbohydrates during endurance exercise are well known, but what is the optimal type and amount of carbohydrate intake? Too much or the wrong type of carbohydrate can cause bloating, nausea, and other symptoms of digestive disturbances. Too little will have no real benefit to your performance. Extreme endurance events like the Tour de France require fairly large amounts of carbohydrate to maintain energy balance. If the athlete is not careful, consuming these large amounts of carbohydrate could cause digestive problems. Combinations of carbohydrates (glucose and fructose for example) ingested at high rates seem to minimize the negative side effects and optimize carbohydrate delivery in these situations.
When Do You Need a Sports Drink?
Carbohydrate ingestion often can enhance performance during exercise of 45 minutes or longer. So to maintain or improve the quality of a training session or to enhance your performance in competition, consuming some form of carbohydrate will probably help. If it is logistically possible in your event, you should consume a carbohydrate-containing sports drink every 15 to 20 minutes. Otherwise, you should drink during recovery periods or breaks in the training session or competition.
What Type of Sports Drink?
Some types of carbohydrates deliver energy at higher rates than others. The greatest rates of energy delivery occur when you ingest a combination of two or more types of carbohydrates. Examples of suitable combinations include maltodextrins and fructose, glucose and fructose or glucose, sucrose and fructose.
How Much Do You Need?
How much you ingest depends on a number of factors, including:
- The intensity and duration of exercise
- The type of carbohydrate (or combination of carbohydrates)
- Your individual tolerance for various volumes and concentrations of carbohydrate solutions. Only trial and error with different drinking schedules during training sessions and in competitions will enable you to discover the best carbohydrate/fluid feeding schedule for you.
The Best Way to Get the Most Benefits
Although carbohydrates in solid foods can deliver carbohydrate, they cannot deliver fluid, which is especially critical in hot environments. Highly concentrated carbohydrate solutions can slow fluid delivery, so you should use a well-formulated sports drink containing not more than seven percent carbohydrate (7g/100 ml or 16.3 g/8 oz). Drink 240 to 600 milliliters (8 to 20 ounces) of water or a sports drink about 10 to 15 minutes before exercise to stimulate fluid delivery from the stomach and then keep the stomach volume high by drinking smaller amounts of a sports drink every 15 to 20 minutes during exercise. Drink enough to minimize the body weight you typically lose during a similar type of training session or competition, but do not drink so much that you gain weight. Drinking too little or too much can be dangerous to your health.
Comments from Amanda Carlson-Phillips, Director of Nutrition, Athletes' Performance
Carbohydrate electrolyte beverages were the first mainstream "supplement" created, in my opinion. They provide your body with the fuel, fluid, and electrolytes known to keep you going strong during intense training or play. I have seen people avoid sports drinks because of the sugar, but your body needs that sugar to fuel it during times of needs.
It is generally recommended that 30 to 60 grams of carbs an hour will keep you going strong. This means that 20 to 32 ounces of Gatorade an hour should keep the fuel flowing for your body to use. So when it comes time to take the field, the court, or hit the training floor for an intense session, take your carb/electrolyte drink with you, in addition to your water. Take one or two 20- to 32-ounce bottles of Gatorade and one or two 20- to 32-ounce bottles of water as well. Plan your hydration strategy based on how hard you plan to exercise and for how long. Know that you will need 20 ounces of carb electrolyte beverage an hour to keep you going—to maintain hydration. Sip on water after that.