How important are fluids? Fluid replacement is probably the most importantnutritional concern for athletes. Approximately 60% of your body weight iswater. As you exercise, fluid is lost through your skin as sweat and throughyour lungs when you breathe.
If this fluid is not replaced at regular intervalsduring exercise, you can become dehydrated. When you are dehydrated, you have asmaller volume of blood circulating through your body. Consequently, the amountof blood your heart pumps with each beat decreases and your exercising musclesdo not receive enough oxygen from your blood. Soon exhaustion sets in and yourathletic performance suffers.
If you have lost as little as 2% of your bodyweight due to dehydration, it can adversely affect your athletic performance. For example, if you are a 150-pound athlete and you lose 3 pounds during aworkout, your performance will start to suffer unless you replace the fluid youhave lost. Proper fluid replacement is the key to preventing dehydration andreducing the risk of heat injury during training and competition. How can Iprevent dehydration? The best way to prevent dehydration is to maintain bodyfluid levels by drinking plenty of fluids before, during, and after a workout orrace.
Often athletes are not aware that they are losing body fluid or that theirperformance is being impacted by dehydration. If you are not sure how much fluidto drink, you can monitor your hydration using one of these methods. 1. Weight:Weigh yourself before practice and again after practice. For every pound youlose during the workout you will need to drink 2 cups of fluid to rehydrate yourbody.
2. Urine color: Check the color of your urine. If it is a dark gold colorlike apple juice, you are dehydrated. If you are well hydrated, the color ofyour urine will look like pale lemonade.
Thirst is not an accurate indicator ofhow much fluid you have lost. If you wait until you are thirsty to replenishbody fluids, then you are already dehydrated. Most people do not become thirstyuntil they have lost more than 2% of their body weight. And if you only drinkenough to quench your thirst, you may still be dehydrated. Keep a water bottleavailable when working out and drink as often as you want, ideally every 15 to30 minutes.
High school and junior high school athletes can bring a water bottleto school and drink between classes and during breaks so they show up atworkouts hydrated. What about sport drinks? Researchers have found that sportsdrinks containing between 6% and 8% carbohydrate (sugars) are absorbed into thebody as rapidly as water and can provide energy to working muscles that watercannot. This extra energy can delay fatigue and possibly improve performance,particularly if the sport lasts longer than 1 hour. If you drink a sports drink,you can maintain your blood sugar level even when the sugar stored in yourmuscles (glycogen) is running low. This allows your body to continue to produceenergy at a high rate.
Drinks containing less than 5% carbohydrate do notprovide enough energy to improve your performance. So, athletes who dilutesports drink are most likely not getting enough energy from their drink tomaintain a good blood sugar level. Drinking beverages that exceed a 10%carbohydrate level (most soda pop and some fruit juices) often have negativeside effects such as abdominal cramps, nausea, and diarrhea and can hurt yourperformance. What does the sodium in sports drinks do’sodium is an electrolyteneeded to help maintain proper fluid balance in your body. Sodium helps yourbody absorb and retain more water. Researchers have found that the fluid from an8-ounce serving of a sports drink with 6% carbohydrates (sugars) and about 110mg of sodium absorbs into your body faster than plain water.
Some parents,coaches, and athletes are concerned that sports drinks may contain too muchsodium. However, most sports drinks are actually low in sodium. An 8-ounceserving of Gatorade has a sodium content similar to a cup of 2% milk. MostAmericans do get too much sodium, but usually from eating convenience-typefoods, not from sports drinks.
What are guidelines for fluid replacement? ?Drink a sports drink containing 6% to 8% carbohydrate to help give you moreenergy during intense training and long workouts. To figure out the percentageof carbohydrate in your drink use the following formula: {Grams ofcarbohydrate/serving}/ {240 g/ serving} X 100 = % of carbohydrate in drink Forexample, 240 ml (a 1cup serving) of a drink with 24 grams of carbohydrate perserving would have a 10% carbohydrate concentration. Almost all drinks have thegrams of carbohydrate per serving and the volume in ml somewhere on thecontainer. ? Drink a beverage that contains a small amount of sodium and otherelectrolytes (like potassium and chloride). ? Find a beverage that tastes good.
Something cold and sweet is easier to drink. ? Drink 10 to 16 ounces of coldfluid about 15 to 30 minutes before workouts. Drinking a sports drink with a 6%to 8% carbohydrate level is useful to help build up energy stores in yourmuscles, particularly if the workout will last longer than 1 hour. ? Drink 4 to8 ounces of cold fluid during exercise at 10 to 15 minute intervals. ‘startdrinking early in your workout because you will not feel thirsty until you havealready lost 2% of your body weight; by that time your performance may havebegun to decline. ? Avoid carbonated drinks, which can cause gastrointestinaldistress and may decrease the fluid volume.
? Avoid beverages containingcaffeine and alcohol due to their diuretic effect. ? Practice drinking fluidswhile you train. If you have never used a sports drink don’t start during a meetor on race day. Use a trial-and-error approach until you find the drink thatworks for you. Bibliography1.
Somer E: Super Natural Power Boosters. Natural Way For Better Health, p. 20-21, March 31, 1995. 2. Impact Communications: Dehydration Poses SeriousHealth Risks.
Nature’s Impact, p. 10, July 31, 1998. 3. Klotter J: Your Body’sMany Cries for Water.
Townsend Letter for Doctors ; Patients 130:510-511,1994 4. Antinoro L: Dodging Dehydration: Are You Getting Enough Fluids?Environmental Nutrition 21:2, 1998 5. Wardlaw GM: Perspectives in Nutrition4:334-344, 1999 6. Anspaugh D and others: Wellness Concepts and Applications3:72-73,159-160
