Avoid Dehydration When Exercising
We are encouraged to exercise more in order to combat obesity and prevent chronic health conditions. But both experienced athletes and beginning exercisers need to be careful about avoiding dehydration when exercising.
Sweating profusely may make you feel like you are having a great workout but you can run into problems of severe dehydration. The body needs to replace a certain amount of water and electrolytes, which are the minerals that are lost in sweat.
Symptoms of dehydration
- The first thing you'll probably experience is thirst. However, there is not a precise relationship to how thirsty you feel and how dehydrated you are. Usually when you get the sensation of thirst, you're already somewhat dehydrated.
- You may get a headache.
- You may feel dryness of the mouth.
- If you are exercising or changing posture, you could feel dizzy.
- You could be urinating less frequently and smaller amounts, so your urine would be dark in color because it would be more concentrated.
- There is also some evidence that both your physical and mental performance capabilities decrease as a result of dehydration. You may not be as sharp in complex cognitive functioning.
Acute dehydration will increase your risk of heat exhaustion and heat stroke. Heat exhaustion causes heavy sweating, fainting and vomiting, and heat stroke occurs when the body temperature rises to 107°F or above.
Causes of dehydration
Many types of stress will cause under-drinking and lead to dehydration.
- Heat exposure and exercise are common causes. When you exercise, a normal response is to sweat to regulate your body temperature. And if you're exercising in hot weather, you have a greater need for sweating to cool the body. As a result, people can become dehydrated from physical exercise, particularly in the heat.
- People can also become dehydrated through the use of some medications. For example, blood pressure drugs such as diuretics are dehydrating because they work by decreasing your total body water.
- Dehydration also result from diarrhea and vomiting.
How much liquids do you need
How much water you need in a day varies. It depends on many factors:
- activity level,
- the environment you're exposed to.
For a normal healthy person, generally, short-term under-consumption of liquids is not too much of a problem, unless you're physically active, because your kidneys will act to reduce your urine output to conserve water.
Likewise, you don't have to worry about taking in too much fluid because your kidneys will remove what you don't need. Over-consumption can become a problem, however, during prolonged exercise (over several hours) because urine output is reduced.
For healthy adults, if you're expending about 3,000 calories a day, the minimal amount of liquids you should take in should be about three quarts of water a day, or roughly three liters. It doesn't matter if the water is contained in food or beverages.
For a very active person in very hot weather, such as an agricultural worker the requirements could be substantially higher.