Skip to main content

Military Health System

Test of Sitewide Banner

This is a test of the sitewide banner capability. In the case of an emergency, site visitors would be able to visit the news page for addition information.

Stay Hydrated for Optimal Performance

Image of A soldier takes a drink from his canteen. Army Pfc. Milton A. Torres takes a drink while on guard duty during a Combat Support Tactical Exercise at Fort McCoy, Wisconsin. Hydration is important for optimal health, particularly in high-heat, dry climates and during outdoors activities. (U.S. Army photo by Army Sgt. 1st Class Gary A. Witte)

You may have heard that dehydration can occur before you feel thirsty. That’s true – but thirst is only one way your body lets you know you’re low on H2O.

Whether you’re conducting operations, working out, or simply spending a lot of time outdoors in high-heat, extreme cold, high-altitude, dry, or humid climates, keeping hydrated is paramount to optimal performance.

“Water is essential for survival,” said Jonathan Scott, a registered dietitian and assistant professor of military and emergency medicine at the Uniformed Services University of the Health Sciences (USU) in Bethesda, Maryland.

“It plays many critical roles in the body, including regulating our body temperature, moistening tissues in the eyes, the nose, the mouth,” said Scott. “It protects our body organs and tissues. It carries nutrients and oxygen to the cells in our body, lubricates joints, helps keep the kidneys and liver functioning properly by flushing out waste products.”

Water comprises about 60% of our body weight. As a result, it also “helps to dissolve vitamins and minerals and nutrients to make them more accessible to your body,” said Scott.

Losing as little as 2% of your body weight through sweating, urinating, and breathing can affect your mental and physical performance. Once you become dehydrated, you may start to feel lightheaded, dizzy, disoriented, fatigued or irritable.

“Feeling thirsty is an indication that there is a fluid imbalance within the body,” added Scott.

That means the amount of fluid you take in versus that which you lose are not in proportion, upsetting your body’s fluid balance. And while you can also take in too much water, dehydration occurs when you lose more fluid than you take in, he said.

However, thirst doesn’t let you know how dehydrated you may be. That, Scott said, depends on a variety of factors, including how long you’ve been feeling thirsty, environmental factors, etc.

“Dehydration is a common issue among our military population,” said Navy Lt. Karla Eslinger, an environmental health officer at Naval Hospital Twentynine Palms aboard Marine Corps Air Ground Combat Center in California.

Urine Hydration chart
Although certain foods can alter the color of your urine, typically, when you’re properly hydrated, your urine should be light colored and clear. (Graphic by Human Performance Resources by CHAMP)

A good way to check your hydration level is through your urine.

Although Scott warned there are foods — such as beets and certain dietary supplement ingredients — that can alter the color of your urine, typically, your urine should be straw-colored (light) and clear when you’re well hydrated, said Eslinger.

“Darker and more concentrated urine suggests dehydration,” she said.

This is important, because “long-term consequences of dehydration can include urinary tract infections, kidney stones, even kidney failure, and on the extreme end of the spectrum, seizures, and ultimately death,” said Scott.

Having a battle buddy is important, he added.

“It's usually somebody else who notices something about you before you notice it yourself,” he said. “A buddy might point out you're dragging behind or seem clumsier, ask if you’re okay, and remind you to drink something.”

How much is good enough?

To be fully hydrated, drinking small amounts of fluids constantly throughout the day is best.

Eslinger highlighted that most people need several hours to drink enough fluids to replace what they have lost through sweat.

“The sooner you get started, the less strain you place on your body from dehydration, which is a primary contributor to heat exhaustion,” she said. “Drinking at shorter intervals is more effective than drinking large amounts infrequently.”

And while the ideal amount of fluids varies by individual due to body weight, activity, environment, and other factors, Scott suggests that a good rule of thumb is aiming “to consume half your body weight in pounds in fluid ounces daily” as a starting point.

According to his suggestion, an individual weighing 150 lbs. should consume about 75 oz. of liquids daily from food and beverages — that’s equal to almost 9.5 cups. But that’s under normal circumstances and activities. If you exert yourself more than usual, such as exercising or working in the heat, you should aim for more.

The Human Performance Resources by CHAMP (HPRC) at USU’s Consortium for Health and Military Performance (CHAMP), recommends aiming for 16-32 oz. of fluid every hour, but no more than 48 oz. per hour, during exercise or high-exertion activities. Likewise, hydrating with water during activity under one hour in duration is sufficient. However, for activity lasting longer than one hour, research supports consuming sports drinks that contain electrolytes and carbohydrates.

In addition, many fruits and vegetables are rich in water and minerals, including melons, berries, peaches, oranges, cucumbers, celery, and lettuce. Milk is also an effective rehydrating option, too, Scott said.

“Dairy milk, for those that tolerate dairy, is one of our best hydrating beverages,” he said. “It naturally contains both of those electrolytes (sodium and potassium), and it’s predominantly made up of water.”

What’s even better, chocolate milk is not only rehydrating, he said, but it also helps to replenish some of the carbohydrates that your body burns during prolonged exercise of 60 minutes or longer.

During those types of activities, “your body uses carbohydrates stored in the liver and muscle in the form of glycogen as its predominant fuel source,” said Scott.

“Chocolate milk has carbohydrates, which helps replenish some of those glycogen stores; protein, which we know is important for the repair process; calcium and vitamin D, which we know are crucial for bone health,” he said. “So, it really is a complete deal.”

What to Do During Deployed Operations?

In a deployed environment, options may be limited during operations. In that case, Scott said, “consuming foods and beverages that replace fluids and electrolytes (sodium and potassium) will typically work out better than just plain water alone, but it's important to incorporate those fluids throughout the entire day.”

To make it easier, Eslinger recommends hydrating before work, during work, and after work — especially for people working regularly in high-heat climates, like the desert.

In general, Scott recommends taking rest breaks from high-exertion activities, keeping track of work-to-rest ratios, and using hydration tables based on different heat categories.

Years of military operations in extreme climates has yielded lessons learned for optimal hydration, such as monitoring the Wet Bulb Globe Temperature. Similar to the heat index, this tool is useful in measuring the heat stress on the body and can help “reduce the number of heat stress injuries for participants and leadership,” concluded Eslinger.

You also may be interested in...

The Dangers of Dietary Supplements

Video
7/11/2022
The Dangers of Dietary Supplements

Did you know that 75% of service members use at least 1 dietary supplement? Experts from the Uniformed Services University discuss the risks and safety concerns of dietary supplements. Learn more about dietary supplements at www.OPSS.org and The Consortium of Health & Military Performance (CHAMP).

What is Performance Nutrition

Video
7/11/2022
What is Performance Nutrition

Learn more about Performance Nutrition and healthy eating habits at the Consortium for Health & Military Performance. https://champ.usuhs.edu/. For more information about the Dietician Approved Fueling stations at your local commissary, go to https://www.commissaries.com/fueling_stations

Performance Nutrition: The Best Ways to Eat

Video
7/11/2022
Performance Nutrition: The Best Ways to Eat

USU professor and nutrition specialist, Jonathan Scott PhD, gives advice on eating healthy. Learn more about the Dietician Approved Fueling stations at your local commissary here: https://www.commissaries.com/fueling_stations

What should I eat after a workout?

Video
6/22/2022
What should I eat after a workout?

Ever wonder how to fuel up post-workout to maximize recovery and support your fitness? Check out these tips from the Human Performance Resources by CHAMP, part of the Uniformed Services University of Health Sciences to enhance your performance! #PerformanceNutrition #FueltoFight #USU #HPRC”

Considering supplements? Stay Informed

Video
6/22/2022
Considering supplements? Stay Informed

Stay informed when considering supplements to help you reach your performance and fitness goals with this video from Operation Supplement Safety, the #DOD dietary supplement resource at the Uniformed Services University of Health Sciences. #PerformanceNutrition #FueltoFight #OPSS #USU

6 Essential Nutrients

Video
6/22/2022
6 Essential Nutrients

Are you getting the right nutrients from your diet? Check out this overview of the six essential nutrients to optimize your performance and fitness from Human Performance Resources by CHAMP at the Uniformed Services University of Health Sciences. #PerformanceNutrition #FueltoFight #USU #HPRC

Tactical Diaper Bags and Other Fathers' Day Tips from a Marine Officer

Photo
6/16/2022
Tortorici Family_725

An experienced military dad offers advice to new service members beginning their parenting journey.

Tactical Diaper Bags and Other Fathers' Day Tips from a Marine Officer

Article
6/16/2022
Tortorici Family_725

“When we deploy, our lives become simpler, while theirs become more complex: In addition to missing their husband and father, they are missing someone who should be helping to shoulder the burden that military life places on kids.”

Air Force Medical Service Launches 'Nutrition Kitchen' Program

Article Around MHS
6/8/2022
graphic for Nutrition Kitchen program

The Air Force Medical Service is launching “Nutrition Kitchen”, a series of online nutritional cooking classes geared toward service members and their families.

Could a Therapy Dog Help with Your Dental Anxiety?

Article
6/2/2022
Air Force Brig. Gen. Goldie, a facility therapy dog at Walter Reed National Military Medical Center, helps reduce anxiety in a patient with complex dental conditions that require multiple appointments. The use of therapy dogs is part of an ongoing study with these patients.

A first-of-its-kind study at Walter Reed National Military Medical Center is researching whether using facility therapy dogs in dentists’ offices could reduce patient anxiety and improve outcomes for military dental treatment programs.

Tips for Military Parents Planning PCS Moves with Children

Article
6/2/2022
Moving can be hard on military families, especially on children. Moving to a new home, going to a new school, finding new friends – it can be unsettling for kids of any age. Yet there are things that service members can do to prepare for a permanent change of station move that can make for a smoother transition for the children.

Moving can be hard on military families, especially on children. Moving to a new home, going to a new school, finding new friends – it can be unsettling for kids of any age. Yet, there are things that service members can do to prepare for a permanent change of station move that can make for a smoother transition for the children.

PTSD Awareness Month - Treatment Works

Infographic
6/1/2022
PTSD - Treatment Works Infographic

Experiencing #PTSD can make one feel hopeless. Fortunately, there are strategies and treatments that WORK to relieve PTSD symptoms. Don’t wait, seek help today. #PTSDAwarenessMonth www.health.mil/ptsd

PTSD Awareness Month - PTSD Awareness

Infographic
6/1/2022
Not Sure if You Have PTSD?

Unfortunately, experiencing trauma is not uncommon. If you’ve experienced trauma and notice symptoms of #PTSD, don’t hesitate to ask your primary care provider about possible treatment. #TreatmentWorks #PTSDAwarenessMonth www.health.mil/ptsd

Walter Reed Service Dogs

Photo
5/27/2022
Luke is a German Shephard facility dog.

Luke, a German Shepherd facility dog at Walter Reed National Military Medical Center, stays with wounded warrior Heath Calhoun at the Military Advanced Treatment Center facility while Calhoun undergoes rehab therapy. Luke is officially a Navy Hospital Corpsman Third Class.

Air Force Surgeon General eyes modernizing capabilities for joint commanders (Part 2)

Article Around MHS
5/27/2022
Military medical personnel at Patrick AFB

Since assuming his role of Air Force Surgeon General, Lt. Gen. Robert Miller has worked to advance the Air Force Medical Service’s capabilities, ensuring it is ready for an evolving joint fight.

Page 3 of 10 , showing items 31 - 45
First < 1 2 3 4 5  ... > Last 
Refine your search
Last Updated: August 10, 2021
Follow us on Instagram Follow us on LinkedIn Follow us on Facebook Follow us on Twitter Follow us on YouTube Sign up on GovDelivery