Fluid: A Constant Need

Find out how much fluid to drink before, during and after exercise

How much do I need?

1.  Drink the recommended amount of fluid every day (see chart below).

Recommended Daily Fluid Intake From Beverages

Teens (14–18 years)

Adults (19+ years)





1.8 L (8 cups)

2.6 L (11 cups)

2.2 L (9 cups)

3 L (13 cups) 

    Source: Dietary Reference Intakes for Water, Potassium, Sodium, Chloride and Sulfate. National Academy of Sciences, 2004.


    2.  Consume additional fluid with activity and in warm conditions. 

    After exercise, quenching thirst may not satisfy the body’s need for fluid. Follow these guidelines to ensure adequate rehydration:

    • Drink 1.5 litres of fluid for each kg of weight loss during exercise (or 3 cups of fluid for each pound).
    • Monitor urine colour and amount. A small amount of dark urine is a sign of dehydration. Plenty of pale urine during the day is a sign of sufficient fluid intake.

    NOTE: Consuming milk, juice, soup, etc. “counts” as part of fluid intake.

    What about “Sport Drinks”?

    During activity:

    • Plain, cool water is sufficient for events or workouts lasting one hour or less. Consume plenty of plain, cool water before, during and after exercise.
    • Beverages containing about 4–8% carbohydrate are beneficial when intense physical activity lasts longer than one hour, as the carbohydrate they contain helps to maintain blood glucose levels. Check the labels of purchased sport drinks; look for approximately 40–80 g of carbohydrate (glucose, glucose polymer, maltodextrin and/or sucrose) per 1 litre of prepared beverage.
    • If you plan to use a commercial sport drink during an event, try it first in training.
    • Make your own sport drink: mix equal volumes of fruit juice and water, and add a small “pinch” of salt.

    After activity:

    • The carbohydrate-to-protein ratio and fluid in chocolate milk make it a great recovery beverage. It provides carbohydrate to refuel muscles, protein to help muscle repair and fluid & electrolytes for rehydration.

    Why is fluid so important?

    Fluid’s most important role during activity is body temperature regulation. Active muscles generate heat, which must be removed. The evaporation of sweat from skin is the most effective way to cool the body. Heavy or prolonged sweating can lead to dehydration which is a major cause of fatigue and poor performance. It increases the risk of cramps, heat exhaustion and life threatening heat stroke. Dehydration can also delay recovery after exercise.

    About BC Dairy

    BC Dairy is a not-for-profit organization representing BC’s dairy farmers.