What’s the big deal about hydration? The answer: Being dehydrated by as little as 2 percent of your body weight can begin to increase fatigue, reduce your athletic performance (mentally and physically), and increase your risk of heat stress. You’re also more likely to get muscle cramps during training and racing. On the other hand, when your body is well hydrated and nourished, you have the capacity to tolerate longer and more intense exercise.
Some individuals are dehydrated prior to exercising or competing, so they’re at a disadvantage even before they start. Hot temperatures accelerate the dehydration process, so fluid requirements are higher in warmer climates. Typically, 80 percent of our water intake comes from a variety of beverages and 20 percent comes from foods such as fruits and vegetables. That’s another reason why it’s important for athletes to not skip meals.
If you find that you’re dehydrated (see the simple tests below), increase your daily fluid intake using an assortment of beverages. It’s easier for your body to absorb fluid if your intake is spread throughout the day than if you try to gulp down too much at one time. Beverages to keep you well-hydrated include water (plain or flavored), milk, juice and fruit smoothies. Certain foods can help keep you hydrated such as fruits and vegetables which are high in water content. For better absorption, it’s important that the beverage you choose is cool, as opposed to warm or room temperature. Recent research has shown that low to moderate amounts of caffeine (less than 300 mg) do not cause dehydration or electrolyte imbalance. Drinking a cup of coffee or a few soft drinks is fine, but higher amounts may have a diuretic effect (they make your body lose water). Alcohol has a sustained diuretic effect, so it is not recommended to meet hydration needs.
At least four hours before a triathlon or other endurance activity, drink 1 ounce of fluid for every 10 pounds of body weight (or 5-7mL/kg) to start the event well-hydrated. Don’t experiment with new beverages before or during a competition; stick with the tried and true.