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Hydration 101: Best Hydration Strategies for Endurance Athletes


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Water is tasteless, colorless, and odorless. Because of its many diverse functions in the body, it is sometimes regarded as the most important nutrient. It is true that you can only survive for about 7 days without water.

There is no debating water is needed for health and optimal performance, however, scientists have a hard time objectively advising endurance athletes on exactly how much they need to drink daily. Most textbooks recommend consuming 10-13 cups of water a day. However, we know that during hard training you will need a lot more!

This blog post is part 1 of a series I’m calling Hydration 101. Over the next few weeks, I will share with you the best hydration strategies (based on the latest research) that you can use to improve your endurance training and racing.

In this first post, I will describe the functions of water and how much to drink prior to exercise. Let’s get going–


Water: Basic Functions in the Body?

Water accounts for about half of your body mass. Also, you have billions of cells in your body that are made up of 60-70% water! Quite impressive indeed–

Water helps to transport oxygen, nutrients and waste products into and out of your cells. Drinking water provides numerous electrolytes (ions which conduct an electric current) including calcium, chloride, fluoride, magnesium, potassium and sodium. Water is necessary for the digestion and absorption of nutrients, and lubricates membranes in the gastrointestinal and respiratory tracts.

Even though it contains no calories, the fluid portion of the cell is where most of the metabolic reactions involved in energy production occur.

Think of water is your body’s coolant, helping to regulate body temperature during exercise, fever and in hot environments. Water also serves as a cushioning component between joints, in the spinal cord and in the brain.


Consequences of Dehydrationshutterstock_157771268

Failure to hydrate appropriately is a chief contributing factor to poor performance during endurance activities, particularly in hot and humid conditions.

It has suggested that performance declines when you lose 3% of your body weight from water. The physical and mental effects of dehydration include:

  • decreased strength
  • decreased speed
  • decreased endurance
  • decreased energy
  • decreases in cognitive processing


How Much Should I Drink Before Exercise?

As mentioned earlier, drinking 10-13 cups should be enough fluid throughout your day to keep your urine clear.  However, if you are planning a long run, especially in warm conditions you will definitely need to pre-hydrate. The good news is that it doesn’t require as much as you might think.

Two hours before your training session, drink 2 cups of water or sports drink. This allows time for the fluid to leave the stomach and the excess removed by the kidneys.

The actual guidelines suggested in most sports nutrition resources are 5-7 mL of fluid/kg body weight (1 kg = 2.2 lbs) 2-4 hours prior to exercise.



If a person weighs 150 lbs, that weight is 68 kg;

therefore 7 mL/kg X 68 kg = 476 milliliters of fluid.

Since 8 ounces is 240 milliliters, 476 milliliters is about 16 ounces, or two glasses of fluid.


Finally, consuming some sodium-containing foods or snacks can help retain the fluid. A beverage with very light sodium would also suffice.



Staying hydrated is paramount to your success as an endurance athlete. The best hydration strategy starts by ensuring you are meeting your daily fluid needs along with being hydrated prior to starting a training session.

In the next post, we will talk about how much fluid is necessary during exercise. Until next week, train hard and stay hydrated!

Now it’s your turn, leave a comment and tell me if you have a hydration plan in place.

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