Is Drinking Cold Water During or After Exercise Good or Bad?

Believe it or not, cold water is absorbed faster by your body than water at room temperature or at body temperature. The American College of Sports Medicine recommends that water and other drinks be chilled when used for exercise.
Cold Water and Cold Drinks Rehydrate Faster
Research has shown that cold water passes through the stomach faster and is therefore sent to the intestines for quicker absorption. During and after exercise, you want to rapidly replace fluids lost due to sweat, so cold water and cold sports drinks are preferred.
Cold Water and Cold Drinks Taste Better
Another reason for drinking cold drinks is that most people find that they taste better, making you more likely to drink more and more often.
Cold Water Does Not Cause Cancer
About.com's Urban Legends Guide dispels another myth, that cold water after a meal causes cancer. No, it doesn't.
What to Drink and When
The 1996 Position Paper of the American College of Sports Medicine recommends:

* Cold: Drinks should be cooler than room temperature.
* Flavored: Drinks should be flavored to make them taste more appealing, helping people to drink more. A squeeze of lemon juice or a pinch of a flavoring can help without adding calories.
* Handy: Drinks should be served in containers that let you drink without disrupting your exercise. This implies it is better to be wearing a water bottle-holding pack when walking rather than relying on water fountains along the way.
* Sports Drinks: Use a sports drink to replace carbohydrate and electrolytes when exercising longer than 1 hour.
* Plain Water: If exercising less than an hour, plain water is just fine, maybe with a squeeze of lemon juice or other flavoring if preferred for taste.
* Drink to Thirst: Updated guidelines in 2006 caution endurance runners and walkers that overdrinking can cause hyponatremia, so exercisers should use thirst as their guide rather than forcing fluids.

Source: http://walking.about.com/od/fluids/f/coldwatermyth.htm