Hydration for Sports

What and when you should drink


Sports Medicine Institute for Young Athletes,

Hospital for Special Surgery

Why are fluids so important during sport activity?

The body relies on water or other fluids to cool itself while you are engaged in physical activity. It does this primarily by providing a means for you to sweat. As the sweat on your skin evaporates, your body cools. When you don’t drink enough fluids before and during activity, you can become dehydrated, and your athletic performance can be impaired. Effects of dehydration include nausea, dizziness and fatigue. Did you know that one of the main causes of upset stomach in distance runners is lack of fluids? More serious cases of dehydration can lead to heat stroke.

What Should I Drink?

  • Choose good old H2O before any activity.
  • Drink water during an activity lasting less than an hour.
  • Drink diluted fruit juices, Gatorade or other low-concentrate sports drinks during an activity that lasts more than 60 minutes. These fluids contain small amounts of carbohydrate to maintain energy, and electrolytes to replenish what is lost when you sweat.
  • Drink water and/or fruit juices or sports recovery drinks after an activity. Fruit juices and specially formulated recovery drinks refuel your muscles after exercise.

How do I prevent dehydration during training or a competition?

First rule of thumb: When you are thirsty…drink. When you feel you have quenched your thirst…drink some more!

Refer to the chart below to find out when and how much you should be drinking…

Timing

Approximate amount of fluids you should drink

2 hours

before activity

2 cups (16 ounces)
Equivalent to a small bottle of water that you can buy in the store

10-15 minutes before activity

2 ½ cups (20 ounces)

Every 15 minutes during activity

½ - ¾ cup (4-6 ounces)
The amount in a juice glass

After activity

2 cups (16 ounces) for every pound lost during activity
Weigh yourself before and after activity. You will likely have lost water weight through sweat during exercise.

posted 8/3/2004