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Heat Exhaustion & Heat Stroke


During the extremely hot summer months, our local foothills can see an incredible rise in temperatures. The soaring sun, little breeze and consistent high temperatures can make for unbearable trail conditions for even the most experienced trail users. While the heat may seem daunting, summer is still a fantastic time to get out and enjoy the trails. To keep you and your trailmates safe and healthy while out on the trails, it is important to remember heat related concerns that can occur when heading outdoors. Heat related illnesses happen when a person’s body temperature rises and becomes unable to cool itself down through sweating. As we perspire, we lose body fluids that need to be replenished. A person experiencing early signs of heat related illness can become dehydrated first, sometimes unbeknownst to themselves.  

Heat Exhaustion is the early stages of heat related illness. Don’t wait until you are thirsty to drink water; drink a minimum of 2 – 4 cups of water per hour of outdoor activity and always carry more than you believe you’ll need.

Heat Exhaustion Symptoms

          Profuse sweating


          Dark-colored urine (a sign of dehydration)

          Pale, cool skin





          Muscle cramps

Heat Exhaustion Treatment

          Stop activity and find the nearest cool and shady location to sit down and rest

          Remove any tight or unnecessary clothing

          Cool the person down with a water bath, spray or fan

          Drink a sports drink or juice, or water if the others are unavailable

          Place a cool cloth around the person’s neck

Heat Stroke is the more serious and potentially life threatening heat illness. Heat Stroke occurs when a person’s core body temperature is above 103 degrees Fahrenheit and the body’s natural cooling mechanisms begin to shut down.

Heat Stroke Symptoms

          High body temperature

          Dry or moist, flushed skin

          Lack of sweat despite the heat

          Dizziness and confusion

          Nausea and vomiting

          Fast breathing and heartbeat

          Behavioral changes such as confusion, slurred speech or staggering


          Fainting or unresponsiveness

Heat Stroke Treatment

          Stop activity and find the nearest cool and shady location to sit down and rest; you may have             to improvise a sunshade if no natural shade is available

          Remove any tight or unnecessary clothing

          Quickly cool the person down by immersing in water up to their neck, spraying, sponging or               showering with cool water

          Place ice packs against the groin, armpits and sides of the neck.

          Call for medical assistance right away.

The best way to enjoy the trails during summertime is to properly prepare for the heat. Ramon Perez, Irvine Ranch Conservancy volunteer and medical practitioner, says, “I would not start a hike after 8am and would try to return to the trailhead before 11am. Avoid exposed trails when possible; love the shade of the trees! Be dressed in loose light-colored clothing, a wide-brimmed hat, sunscreen and sunglasses and keep your pack weight light – leave your big backpack and heavy gear at home. Remember to frequently check on your hiking partners for any discomfort that suggests dehydration, give them a friendly pat on the back while checking to be sure they are still sweating and drink water often, even if you don’t feel thirsty.”

Remember to pace yourself and do what is best for you. Limit your outdoor activities to the cooler early mornings or the breezy afternoons. And always remember the three rules of hydration: Pre-hydrate (before your activity), hydrate (during your activity) and re-hydrate (after your activity). Avoid alcoholic beverages the night before a planned outing and coffee the morning of an outing on an expected hot day. Sports drinks can be helpful afterward to replenish minerals lost during activity and can help avoid fatigue and muscle cramping.

Hiking with others is always recommended, but especially during hotter weather. Louie Liwanag of OnSite Training, a first-aid training provider states, “The key is for a responder to recognize the signs and symptoms and treat for heat exhaustion before the patient progresses to heat stroke. Oftentimes, individuals focused on their activity may not realize that they are experiencing heat exhaustion until they start having some obvious and potentially life-threatening symptoms.” Ensure that you and your trailmates are looking out for each other at all times.

No matter what the time of year or the conditions, knowledge of what to expect and being properly prepared will be of great benefit when signs of trouble arise. Stay cool and hydrated out there this summer!