As the temperatures soar, active 50+ exercisers (myself included!) need to pay special attention to hydration. There are some who say that thirst should be your only guide for hydration, but that advice could be dangerous as we age. When older adults exercise, especially in hot and humid climates, they have a diminished sensation of thirst. And we know that “normal” thirst kicks in after you are already thirsty so waiting for thirst may lead to heat illnesses.
Aging also brings about other changes in normal physiology that contribute to dehydration. Our sweat rate changes, our kidneys change the way they handle fluids and electrolytes, like sodium and potassium, and there is an altered blood flow response. All of these normal age changes mean that we need to be aware of hydration and adopt strategies to keep us hydrated during the physiological stress of exercise.
In addition, many 50+ take medications that contribute to loss of body water. Chief among the drugs are common blood pressure medications that act as diuretics which can increase water loss. When you add in other common drugs, caffeine and alcohol, both which are mild diuretics, hydration becomes even more important.
How do you know if you are dehydrated? This question is of great interest to researchers and unfortunately there is no single, easy test to assess hydration. Until there is an easy reliable and valid test, the best strategy is to weigh yourself before and after exercise. For every pound loss, drink 16-24 ounces for every pound loss during exercise. If you gain weight after exercise that means you are most likely overhydrated, but a loss of 1 pound or less means you are doing pretty well at hydrating. Another way to assess hydration is by monitoring urine volume and color. A dark colored urine usually means you are dehydrated (although some dietary supplements like vitamins with a high concentration of riboflavin can cause a bright colored urine) as well as infrequent urination.
Here are some tips to keep you hydrated:
- Monitor body weight before and after exercise to gauge fluid loss
- Monitor urine volume and color
- Drink fluids before activity and during activity when exercising in hot, humid environments
- Replace fluids after exercise
- Eat foods with high water content (fruits and vegetables)
- Consume fluids with meal
- Use sport drinks if you are a heavy sweater and/or a salty sweater; if watching calories, try the “light” verisons that provide some carbohydrate but with the same electrolyte content as the regular sport drinks.