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Adequate hydration is an important issue for the human body 365 days per year. Activities performed in the summer heat and humidity require special attention to fluid intake and replacement.
Dehydration increases the likelihood of heat injury. We sweat to cool our bodies. Humidity, especially when combined with high temperatures, reduces the evaporation of sweat from the skin thus reducing the effectiveness of sweating to cool the body. This causes us to sweat more in a further attempt to cool the body. The more humidity, the more you sweat, the more you dehydrate!
You can effectively reduce your chances for injury by consuming the proper amounts of fluid before, during and after exercise. Here are some guidelines to follow:
Prehydrate — Start hydrating four hours before activity by drinking two to three cups (16-24 ounces) of fluid, preferably water. Weigh yourself.
Watch for signs — If signs of dehydration are present, such as not needing to urinate or urine dark in color, drink another one or two cups (8-16 ounces) two hours before activity.
Hydrate — Drink 6-12 ounces for every 15-20 minutes of activity.
Recover — After activity, weigh again and drink three cups (24 ounces) for each pound lost.
So when is just water not enough? Most of the time, plain water is adequate. Consuming beverages such as “sport drinks” containing electrolytes and carbohydrates can provide benefits over water alone under certain circumstances.
A concentration of carbohydrates between 4-8 percent provides fuel for the muscles and brain without impairing stomach emptying. Electrolyte sodium increases fluid absorption and stimulates thirst resulting in increased fluid intake. However, you can also accomplish this by eating a salty food, such as a few saltine crackers, and drinking plain water.
The bottom line is to think of sport drinks as a fluid replacement rather than an electrolyte replacement. If you like the taste of what you’re drinking, you’re apt to drink more of it. One disadvantages of these drinks is that calories add up quickly, which can be an issue if you are trying to control weight.
Here are some guidelines to follow:
Drink plain water when your exercise is less than one hour and low to moderate in intensity.
Drink sports drinks when your exercise is greater than 1.5 hours and moderate in intensity or greater than one hour and high intensity or you are exercising in extreme heat.
Is it possible to drink too much water? Yes. Hyponatremia is a condition where sodium levels in the bloodstream drop too low. A number of participants from a variety of occupational and athletic/recreational activities have been hospitalized for this condition and several having died. Therefore, under most circumstances, you should not ingest more than 1.5 quarts of water per hour.
Finally, never use alcohol as a source of fluid. Alcohol is a diuretic and will actually dehydrate you further. Also, some alcoholic beverages delay the rehydration process. So, on those hot and sweaty summer days, a glass of water is more refreshing to your body than a cold beer.
Physical exercise can cause high sweat rates and substantial water and electrolyte losses, particularly in hot and humid weather. If sweat water is not replaced, individuals will dehydrate during physical activity. Excessive dehydration can degrade exercise performance and increase risk of heat illness.
What do you do to stay hydrated?
Adequate hydration is an important issue for the human body 365 days per year. Activities performed in the summer heat and humidity require special attention to fluid intake and replacement.
Dehydration increases the likelihood of heat injury. We sweat to cool our bodies. Humidity, especially when combined with high temperatures, reduces the evaporation of sweat from the skin thus reducing the effectiveness of sweating to cool the body. This causes us to sweat more in a further attempt to cool the body. The more humidity, the more you sweat, the more you dehydrate!
You can effectively reduce your chances for injury by consuming the proper amounts of fluid before, during and after exercise. Here are some guidelines to follow:
Prehydrate — Start hydrating four hours before activity by drinking two to three cups (16-24 ounces) of fluid, preferably water. Weigh yourself.
Watch for signs — If signs of dehydration are present, such as not needing to urinate or urine dark in color, drink another one or two cups (8-16 ounces) two hours before activity.
Hydrate — Drink 6-12 ounces for every 15-20 minutes of activity.
Recover — After activity, weigh again and drink three cups (24 ounces) for each pound lost.
So when is just water not enough? Most of the time, plain water is adequate. Consuming beverages such as “sport drinks” containing electrolytes and carbohydrates can provide benefits over water alone under certain circumstances.
A concentration of carbohydrates between 4-8 percent provides fuel for the muscles and brain without impairing stomach emptying. Electrolyte sodium increases fluid absorption and stimulates thirst resulting in increased fluid intake. However, you can also accomplish this by eating a salty food, such as a few saltine crackers, and drinking plain water.
The bottom line is to think of sport drinks as a fluid replacement rather than an electrolyte replacement. If you like the taste of what you’re drinking, you’re apt to drink more of it. One disadvantages of these drinks is that calories add up quickly, which can be an issue if you are trying to control weight.
Here are some guidelines to follow:
Drink plain water when your exercise is less than one hour and low to moderate in intensity.
Drink sports drinks when your exercise is greater than 1.5 hours and moderate in intensity or greater than one hour and high intensity or you are exercising in extreme heat.
Is it possible to drink too much water? Yes. Hyponatremia is a condition where sodium levels in the bloodstream drop too low. A number of participants from a variety of occupational and athletic/recreational activities have been hospitalized for this condition and several having died. Therefore, under most circumstances, you should not ingest more than 1.5 quarts of water per hour.
Finally, never use alcohol as a source of fluid. Alcohol is a diuretic and will actually dehydrate you further. Also, some alcoholic beverages delay the rehydration process. So, on those hot and sweaty summer days, a glass of water is more refreshing to your body than a cold beer.
Physical exercise can cause high sweat rates and substantial water and electrolyte losses, particularly in hot and humid weather. If sweat water is not replaced, individuals will dehydrate during physical activity. Excessive dehydration can degrade exercise performance and increase risk of heat illness.
What do you do to stay hydrated?
