Tips to Keep Athletes Hydrated


It is important to stay properly hydrated. Provided are recommendations to avoid both dehydration and overhydration.

About dehydration:  During exercise sweat losses are great, especially in hot weather conditions. When athletes sweat, water and electrolytes are lost. If the loss is not replenished this could lead to a decrease in performance and potential life-threatening, heat-related injuries. Younger athletes are more at risk for dehydration and heat injury.

Signs of dehydration:

  • muscle cramps
  • weakness
  • inability to concentrate
  • nausea
  • dizziness

When fluid balance is achieved, athletic performance will be at its best. Optimal hydration should replace sweat loss.

What does a child need to drink?

Many electrolytes are lost along with fluid during exercise. The Institute of Medicine recommends that sodium, potassium and carbohydrates be included in replacement beverages. An adequate amount of sodium may help to prevent cramping [ACSM 500-700 mg Na/L (20-30 mcg/L) sweat 30-60 mcg/L] and carbohydrates provide extra energy. Cramping for nutritional reasons is almost always due to a loss of fluid and sodium.Note that the amount of electrolytes in a sports drink is less than the amount in sweat.

Water vs. sports drinks (20 oz. in average bottle):







8 oz.




Powerade ®

8 oz.


53 mg

32 mg

Gatorade ®

8 oz.


110 mg

30 mg

G-2 ®

8 oz.


110 mg

30 mg

Monitoring hydration

1. Sweat rate: To determine sweat rate first weigh your child naked or in typical workout gear. After working out for about an hour, change into dry clothes, wipe off all sweat and weigh the child again. The difference in body weight is your sweat rate assuming you did not drink or eat during the workout.

1 pound = 16 oz. of sweat. For every pound lost, replace with 16 oz. of fluids within 24 hours.

Weight gain or no loss = overhydration

1 – 3 pounds = very healthy hydration

4 – 5 pounds = concerned about hydration

6 – 8 pounds = very concerned about hydration

2. Specific gravity: Testing the specific gravity of your child’s urine will also help to assess hydration. Test strips are available at most drugstores. To use the test strip, urinate in a cup, dip the strip in the urine and compare the color on the strip to the colors on the package. Urine specific gravity should be within the range of 1.010 to 1.020.

3. Urine color: Assessing urine color during exercise is another way to monitor hydration. The picture below serves as a guide in determining if you are in a healthy hydration range.

How much hydration does my child need?

The amount of fluid and electrolytes needed for exercise depends on many different factors which affect sweat loss including age, gender, clothing, weather, medications, recent heat exposure, intensity and duration of exercise and fitness level. Hydration is especially important to endurance athletes, those athletes who have more than one practice or game in a day and those who have an increased sweat loss.

Before exercise: When beginning exercise it is important for athletes to be well hydrated. At least 4 hours before physical activity begins, drink a 1/2 cup of fluid for every 40 pounds of body weight (example: if your child weighs 150 pounds, she would need about 2 cups of fluid).

During exercise: Hydrating during exercise is very important but amounts will differ based on an individual’s sweating and duration and intensity of exercise. Hydration should occur during every break. Sports drinks should be used for intense exercise lasting 60 minutes or more. In hot, humid conditions, consider a sports drink for exercise of greater than 30 minutes.

After exercise: Once completing exercise, it is essential to replace what was lost. If a normal diet is followed, one should recover properly, but it is important to add foods high in sodium to replace the sodium lost by sweating. By adding extra sodium into the diet in the recovery phase, thirst is increased and fluid lost is recovered. Individuals should drink 3 cups of fluid for every pound lost during exercise. Fruits and vegetables are hidden sources of fluid.