This is an excerpt from Fitness After 50 by Walter Ettinger,Brenda Wright & Steven N. Blair.
Becoming dehydrated is easy, especially when you are active. Dehydration can cause serious problems for older adults. Severe dehydration can cause you to be hospitalized.
During activity it's normal for your body to produce heat and for you to sweat. If you are wearing the right clothing and the temperature and humidity are not excessive, the sweat will evaporate off your skin to cool your body. If you are exercising in hot and humid conditions, you will sweat more than normal. You must replace the water that you are losing to avoid becoming dehydrated. As you get older, you will not be able to rely on feeling thirsty to remind you to drink water.
Dehydration can lead to overheating and heat stroke. Both are serious conditions. Dehydration can also cause constipation, make kidney problems worse, and cause blood pressure to drop.
Taking diuretics (“water pills”), antihistamines, antidepression medicines, and other medicines can cause dehydration. Drinking caffeinated and alcoholic beverages can also cause you to lose fluid and need more water.
Be sure to drink water throughout the day to prevent dehydration. You can tell if you are becoming dehydrated if your urine becomes dark yellow. Your goal should be to drink six to eight cups of liquids every day. Drink one cup of water before and after activity—more in hot and humid weather. If you are active for more than 30 minutes, drink another cup of water during your activity.
Plain water is the best liquid to drink. Other nonalcoholic, decaffeinated drinks, such as fruit and vegetable juices, lemonade, and low-fat or nonfat milk, count as fluids. You don't need to buy sports drinks to replace the minerals lost through sweating unless you are working hard for several hours. If you have a problem with incontinence, don't manage the problem by drinking less water. Talk to your doctor about ways to drink the water that you need and control incontinence. Give yourself time to adjust to activity in hot or humid weather or at high altitude. Also, remember to wear the right clothing for the activity that you will do.
Warning Signs of Overheating and Heat Stroke
Stop, get out of the sun, and drink water if you have any of these symptoms during activity.
- Light-headedness or dizziness
- Clumsiness or stumbling
- Nausea or vomiting
- Muscle cramps
- Excess sweating or no sweating at all