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Tough Workouts? You Could Be Dehydrated

Mar 27, 2017
 Comfy sweats, high-performance trainers, and a groovy playlist: Now that spring weather is here, many of us will start new exercise routines.

Unfortunately, all the gear in the world won't help us if we forget a vital part of successful workouts: staying hydrated.

"Dehydration is when the amount of water in your body falls below a normal, heathy level," says Traci Thompson, MS, Director of PEAK at University of Utah Health's Wellness & Integrative Health.

Why Is Dehydration Harmful?

Most of us probably know that dehydration can make us tired. But did you know dehydration can actually make it harder to exercise?

"Dehydration impairs your body's ability to regulate heat, which causes your body temperature and heart rate to rise. This causes you to feel more tired during exercise," says Thompson.

Dehydration also weakens your mental function. This can negatively affect your:

  • motor control,
  • decision making,
  • and concentration.

When your body is dehydrated, your stomach also passes food into the small intestine more slowly than normal. This can cause your stomach to hurt.

All of these differences in your body can reduce your performance during exercise.

How to Prevent Dehydration

"If you drink regularly during exercise, you can prevent the worst side effects of dehydration. Drinking enough water will prevent a decline in your concentration and skill level," explains Thompson.

Drinking the right amount of water can also:

  • prevent your heart rate from rising,
  • prevent body temperature from rising,
  • and improve performance during exercise.

How Much Fluid Do I Need?

Your body needs different amounts of water before, during, and after exercise.

  • Before exercise, you should drink one cup of water at least four hours before you start exercising.
  • During exercise, you should drink 120-150 ml (4-5 ounces) of water every 10-15 minutes.
  • After exercise, you should drink enough water to double the amount of water your body lost during exercise.

How Can I Tell If I'm Dehydrated?

One of the easiest ways to tell if you're dehydrated is to look at the color of your urine. Your urine should be a light color (not dark).

But if you're scientifically-minded, you can actually measure how much water you should drink after you exercise using the weight test.

Here's the simple formula:

  • Weight (before exercise) — weight (after exercise) = fluid loss

So, if you weigh 150 pounds before exercising, but weigh only 148 pounds after exercising, you have lost two pounds of water weight.

To replace the amount of water your body has lost: Drink 24 ounces of water (3 cups) for each pound lost. So, 24 ounces X two pounds = 48 ounces (or 6 cups of water).

Be fit! Just be sure not to sabotage your workouts—stay hydrated.