People who exercise at a high intensity for more than 30 minutesshould consume a sports drink rather than plain water to rehydratetheir bodies most efficiently, concluded experts at a recent AmericanCollege of Sports Medicine roundtable.
'These beverages replace not only fluids lost during exercise,but also depleted energy stores and electrolytes,' notes CarlGisolfi, professor of exercise science at the University of Iowa andchairman of the meeting held at ACSM headquarters in Indianapolis.'Especially in the case of prolonged exercise, oral rehydrationsolutions optimize the body's ability to absorb water andcarbohydrates.'
While the panelists recommended commercially available sportsdrinks for their precise scientific formulation, some nutritionistsargue that home-made beverages, such as diluted fruit juice, areacceptable for most people.
'Ordinary mortals don't have to spend lots of money on expensivesports drinks,' says Boston sports nutritionist Nancy Clark. 'Ifyou're an athlete with a capital A, sports drinks will replace sweatlosses the fastest. But most recreational athletes will do fine withwater and fruit juice.'
Sports drinks also are 'more palatable (than water) so peoplewill drink more,' adds physiologist Ronald Maughan of the Universityof Aberdeen in Scotland. 'Adults and children must be encouraged todrink before, during and after exercise' to boost performance, reducethe risk of dehydration and heat illness and aid in recovery fromactivity. Because each person's physiology and exer cise goals are unique, Maughan says, 'there's no ideal oralrehydration solution that fits all needs.'
A basic, all-purpose sports drink should contain a small amountof sodium, which stimulates carbohydrate and water absorption, andbetween 5 percent to 8 percent carbohydrate. Beverages with higher levels ofcarbohydrate, such as sodas, are not as quickly absorbed.
Experiment with a variety of sports drinks to find the one thatworks best for you, said experts at the conference. Weigh yourselfbefore and after exercise to estimate how much you need to drink; foreach pound lost during activity, drink a pint (two cups) of fluid.
In hot weather, it's also important to consume some salty foodsunless you're on a sodium-restricted diet.
'Many health-conscious people avoid salt without reason,' Clarksays. 'You don't have to add salt to your food, but if you have asalt craving grab a handful of pretzels.' This is particularlyimportant for weekend warriors who may not be acclimatized to theheat; they lose more salt in their sweat than people who exerciseoutdoors regularly, she notes in Nancy Clark's Sports NutritionGuidebook.
And while the old rule about drinking eight, 8-ounce glasses ofwater a day is fine for most people, it may be insufficient for thevery active.
'The goal is never to experience thirst,' says Ann Grandjean,director of the International Center for Sports Nutrition in Omaha,Neb. 'If you're thirsty, you're already dehydrated. Losing aslittle as 2 (percent) to 3 percent of your body weight by sweat cancause a decrease in concentration, coordination, strength andstamina.'
If you don't consume enough fluids during exercise, notesRunner's World nutrition columnist Liz Applegate, 'your bloodthickens, making it tough for your heart to pump efficiently andcheating your muscles of needed oxygen.'
In her book, Power Foods, she offers these hydration hints: Start the day with 8 to 16 ounces of water and take water breaksevery 30 to 45 minutes until bedtime. Tank up with 8 to 20 ounces of water about 15 minutes before workingout. Drink large amounts of water 24 to 36 hours before competition. Drink water or a sports drink during your workout. After exercise, down several cups of water or sports drink.
'Drink more in warm weather, during travel and at higheraltitudes,' writes Applegate, who says illness, sunburn and dietingalso create a need for more fluid.
Remember that not all fluids hydrate. Alcoholic beverages andthose with caffeine have a dehydrating effect, so chase that mug ofcoffee or beer with a glass or two of water.
