Exercise and Fluid Replacement Guidelines
The guidelines for fluid replacement have changed over the years as we've learned more about the body and how important water is to our health.
Each of us will have individual requirements when it comes to fluid replacement. We exercise differently, sweat differently and workout in different climates and environments but, guidelines, set out by the American College of Sports Medicine, can help you figure out how to stay hydrated:
- Drink about 17 ounces of fluid 2 to 3 hours before exercise.
- Drink about 8 to 10 ounces of water 10 to 20 minutes before exercise.
- Drink about 8 to 10 ounces of water every 15 minutes or so during your workout. You may find sipping water throughout your workout works as well.
- If you exercise for more than an hour, consider a sports drink. Learn more about the the best sports drinks
- Continue drinking water after your workout to replace any fluids lost.
The Symptoms of Dehydration
Dehydration can lead to a number of problems when you're exercising including dizziness, fatigue, diarrhea, vomiting, heat exhaustion or, extreme cases, heat stroke. These symptoms may be a sign you're dehydrated:
- Headache
- Feeling dizzy or lightheaded
- Very dark urine (when you're properly hydrated, your urine is light or clear)
- An inability to urinate
- Dry mouth
If you do experience these symptoms, stop what you're doing and consider drinking a sports drink to help balance out your electrolytes.
The Symptoms of Hyponatremia
Some of us get so worried about dehydration, we end up drinking a little too much water, which can lead to water intoxication. This happens when you lose too much salt through sweating, and, though you're replacing your fluids with water, you're not replacing the salt you've lost. While this is rare, it can be serious, leading to seizures, a coma or, in extreme cases, death. Some symptoms to watch out for include:
- Muscle cramps
- Nausea
- Disorientation
- Confusion and slurred speech
You can treat hyponatremia by eating salty foods or drinking a sports drink that contains sodium.
Sources:
American College of Sports Medicine. (2006). "Dehydration." ACSM's Guidelines for Exercise Testing and Prescription. Baltimore, MD: Lippincott Williams & Wilkins.
Coleman, Ellen. Fluid Replacement Guidelines for Exercise. Today's Dietitian. March, 2008. 10(3): 10.
Wendt, Daniel. Thermoregulation during Exercise in the Heat: Strategies for Maintaining Health and Performance. Sports Medicine. 37(8):669-682, 2007.
