Last week I introduced the subject of hydration.
I discussed how one gets dehydrated and how to prevent this unfortunate situation. This week I will continue this topic, but focus on staying hydrated.
How much fluid one should consume on a daily basis depends on one’s lifestyle, in addition to how active one is and the type of physical activity one performs.
It is best to speak with one’s doctor as to the specific amount of water one should consume. As always, what is written here is meant to be taken as general guidelines.
The American Dietetic Association recommends that women should drink nine cups of water a day and men should drink 13.
People at risk for dehydration should consume more than the above recommendations.
For those who do not enjoy the taste of water, it is recommended to drink flavored water or to add a slice of lemon.
Juices and tea can also help.
There are also several foods that contain high amounts of water such as
watermelon (92 percent), lettuce (95%) and broccoli (91%). Soups are
also recommended, as are yogurt and popsicles.
Sports drinks can also help and there are several types on the market.
If one has an athletic event that lasts for over 90 minutes, the
carbohydrates that are part of sports drinks could be of benefit.
A sports drink with 15-18 grams of carbohydrate in every 0.2 liters, is recommended.
Higher carbohydrate content can delay the absorption of water, which
could lead the athlete down a path of cramps, dehydration, nausea or
It is advised that one experiment with different sports drinks before practices and not before a competition.
It is never a bad idea to arrive fully hydrated to a competition.
Keep in mind where you are performing the competition and adjust your drinking habits accordingly.
If the athletic event is particularly long, it is a good idea to not just drink before the event, but also during it.
It is advisable not to drink more than you will lose by sweating, if you do not want to gain weight during the athletic event.
For those interested in measuring their sweating rate, I have included a simple formula to calculate it.
Step 1: Measure body weight before and after one hour of exercise. It is
advisable to do this under conditions that will be as identical as
possible to those you will compete under. While weighing yourself, make
sure that you are wearing as little clothing as possible, and remove
After you finish exercising, towel dry and measure your weight. It is
also good to make a note of how many liters of fluid you consumed during
Step 2: Plug in your numbers to the following formula: Sweat loss
(liters) = Body weight before exercise (kg) – Body weight after exercise
(kg) + fluid consumed during exercise (liters).
If you want to know your sweat rate per hour, all you have to do is
divide your sweat lost by the exercise time (in minutes) and multiply by
When you finish exercising, it is very important to rehydrate your body.
When you sweat, your body loses not just water, but also salt, and therefore both need to be replenished.
It is advisable to drink 1.2-1.5 liters of fluid for each kg of weight that you have lost during exercise.
Make sure that your beverage or food choice after exercise contains sodium.
If you lost a lot of sweat, you can always add a little extra salt to your meal.
However, I would not recommend taking salt tablets to replenish the levels of salt in your body.
Next week, I will continue our series on nutrition, with a focus on supplements.
The above information is supplied by Yonatan Kaplan PT PhD (Candidate).
Director, Jerusalem Sports Medicine Institute, Lerner Sports Center,
For further details, visit www.jsportmed.com, email [email protected]
or call Yonatan at 054-463-9463.