One of the most essential components of the human body, water is responsible for regulating the body's temperature, cushioning and protecting vital organs and supporting the digestive system.
Muscle tissue is composed of 75% water; for fatty tissue, that number is about 10%. Water also acts within each cell to transport nutrients and dispel waste. Because the human body is more than half water, it's impossible to sustain life for more than a week without it.
Benefits of water
Water's many benefits include:
- Promoting weight loss and aiding in weight maintenance
- Increasing brain power and energy
- Improving memory, mood, cognitive and motor skills
- Maintaining regularity and decreasing constipation
- Boosting the immune system
- Preventing bad breath and headaches
- Improving overall health
Water loss
Because water is needed for the healthy function of all internal organs, you need to replace the amount lost each day during basic activities. It's recommended that women consume 2.7 liters (91 ounces) daily and that men consume 3.7 liters (125 ounces) through various beverages (80%) or in food (20%).
If you're active, you need to drink even more, particularly if you're exercising in hot weather. In one hour of exercise, the body can lose more than a quart of water, depending on exercise intensity and air temperature. If there's not enough water for the body to cool itself through perspiration, you're dehydrated. Drinking water is especially important during the 24 hours prior to vigorous exercise.
You can meet your body's water needs over the course of a day through a variety of fluids and foods including juices, soda, smoothies, tea, lemonade, soups, fruits and vegetables.
Dehydration dangers
If you exercise regularly, maintaining a constant supply of water in the body is essential to performance. Dehydration leads to muscle fatigue and loss of coordination. Even small amounts of water loss may hinder athletic performance.
In a dehydrated state, your body is unable to cool itself efficiently, leading to heat exhaustion and possibly heat stroke. Without an adequate supply of water, you'll lack energy, and your muscles may develop cramps. Here in the desert, you're losing water due to extreme temperatures even when you're not exercising.
To prevent dehydration, exercisers must drink before, during and after a workout.
Fluid balance and replenishment
It's important to drink even before signs of thirst appear. Thirst is a signal that your body is already on the way to dehydration. Drink more than your thirst demands and continue to drink throughout the day.
One way to check your hydration level is to monitor your urine. It should be plentiful and pale yellow unless you're taking supplements, which will darken the color for several hours after you've taken them.
During exercise, water is the best fluid replenisher for most individuals, although sports drinks help replace lost electrolytes during high-intensity exercise exceeding 45 to 60 minutes. If you sweat profusely during exercise and your sweat contains a high amount of sodium (you may notice salt stains/rings on your athletic wear), choose sports drinks and ensure that your diet contains adequate sodium to prevent hyponatremia (water intoxication).
Contrary to popular belief, scientific evidence suggests that moderate caffeine intake doesn't compromise exercise performance or hydration status. However, alcohol consumption can interfere with muscle recovery from exercise and negatively affect a variety of performance variables.
Hydration hints
It's easy to prevent dehydration with a variety of refreshing beverages, so drink up!
- Drink 17-20 ounces of water two to three hours before you start to exercise
- Drink 8 ounces of fluid 20 to 30 minutes prior to exercise or during warm-up
- Drink 7-10 ounces of fluid every 10 to 20 minutes during exercise
- Drink an additional 8 ounces of fluid within 30 minutes after exercising
- Drink 16-24 ounces of fluid for every pound of body weight lost after exercise
- Rehydration occurs faster in the presence of sodium, whether you get it in a sports drink or in food