Hiking and Dehydration by Lindsey Burt

lindsey burt webHiking is a great activity for all ages and an excellent form of exercise, but a day hiking in the sun can quickly go from fun to dangerous if you are not prepared. When exercising in the heat for long periods of time, dehydration is of utmost concern.  Dehydration occurs when there’s an excess loss of fluids and electrolytes, or not getting enough fluid, or both.  When walking in the heat, your body perspires about one quart of fluid every hour. This figure is even more if you’re hiking uphill or in direct sunlight.  The human body is made up of about 60 percent water and it is important to keep replenishing lost fluids.  Dehydration is dangerous because our body needs water to maintain blood and other fluids to function.

Here are some useful tips to help prevent dehydration during your next hike:

  • Start hydrating preferably the day before, but at least one hour before your hike – bring water.
  • Hike early in the morning because temperatures are cooler. According to the National Park Service, most people who need emergency treatment for heat related illnesses hike between 11am – 3pm. It is best to avoid these times as the sun is the most direct and temperatures are at their peak.
  • Instead of wearing less clothing, it is actually beneficial to wear lightweight long sleeves and light colored clothing.
  • Bring at least 3 liters of water for a day hike in the sun. To make it easier to carry the water, carrying a bladder type system such as a Camelbak.
  • To stay hydrated the entire hike, sip your water slowly throughout the day.
  • Drink a sports drink to replenish your body if it needs electrolytes. If it is a hot day and you are sweating a great deal, it is important to replenish your electrolytes. Sweating causes you to loose important electrolytes needed by the body, such as potassium and sodium.


The signs and symptoms of dehydration are thirst, dry mouth, dark yellow to amber colored urine, and dry cool skin. The sooner you notice the signs, the quicker you can react by rehydrating to prevent dehydration. Severe dehydration is exhibited as no urine output, dry skin, lack of sweating, light-headedness, irritability and confusion. If you suspect someone is severely dehydrated, you need to seek medical attention right away. Hot conditions in the summer can overwhelm the body’s cooling mechanism making dehydration worse. This mixture can lead to a potentially fatal condition called heat stroke.  In order to prevent your seemingly harmless hike from turning serious, it is important to remember, thirst is the first warning sign of dehydration.

The information provided is for general interest only and should not be misconstrued as a diagnosis, prognosis or treatment recommendation. This information does not in any way constitute the practice of medicine, or any other health care profession. Readers are directed to consult their health care provider regarding their specific health situation. Marque Medical is not liable for any action taken by a reader based upon this information.



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