This week, the northeast suffered with record breaking high temperatures. Here in New York, the streets were like saunas, but diehard runners still got out in the middle of the afternoon for their lunchtime runs along the Westside Greenway. Working out outside can be dangerous at these high temperatures, especially if you are unprepared.

The human body’s core temperature can go above 40 °C (104 °F) while working out due to heat produced by muscle contractions. The body cools itself down through its approximately 2.6 million sweat glands, and can lose up to 2 liters of water per hour during high intensity exercise.

I know the dangers of excessive dehydration first hand. I’ve ended up in the hospital twice after summer races with a migraine, an IV bag stuck in my arm, and an irregular heartbeat. It was not that I didn’t consume enough water, it was that I was dehydrated to do lack of electrolytes. Plus, the fact that my skin in paper white and absorbes the sun with little protection from melanin puts me in the danger zone most of the time. But I love to race and I love the outdoors, so I refuse to let this stop me, even though I can suck down IV bags like a champ (at least that’s what the nurses tell me).

As we approach summer, there are certain precautions that we all have to take to protect against the heat while working out, whether we choose to run at high noon (not recommended) or go for a bike ride after work.

Here are some tips that have helped me:

Know the symptoms of dehydration.

According to the American College of Sports Medicine, warning signs of dehydration include: thirst, irritability, headache, dizziness, muscle cramping, unusual fatigue, nausea, vomiting, hyperventilation, and confusion or problems walking.

Drink water, but not too much.

Avoid extreme excessive water consumption, which can lead to hyponatremia. Hyponatremia occurs when the body has too much water in its system and electrolytes like sodium are so low that the body’s major organs start to shut down. Hyponatremia is deadly. If you are going to be exercising outdoors, make sure to wear a water belt and add salt tablets to your running pack. nuun brand electrolyte tablets come in a variety of flavors, and they come in an easy to pack tube dispenser.

Begin your workout fully hydrated.

Drink 16 oz. of fluid 2 hours before your workout to start your exercise session fully hydrated. You’ll only want to replace what you lose, not the additional hydration deficit.

Cut out alcohol and caffeine in the heat.

If you know that a heatwave is on its way, don’t drink coffee the morning of or have cocktails the night before. Caffeine and alcohol will suck water out of your system.

Calculate your sweat rate.

It’s easier than you think to calculate your sweat rate. Simply calculate weight lost in one hour of exercise plus amount of fluid consumed during the hour of exercise. By knowing your sweat rate, you’ll be able to accurately measure how much fluid you need to replace your water lost without over hydrating.

Here are some tips from the DailyBurn community on how to beat the heat:

“When I come home from working out, I like to throw on my swimsuit immediately, turn on the fun sprinkler on the lawn, and lay out for about 10 minutes while the water falls over me. It cools me down real quick and relaxes me.” – Michelle
 
“Running cold water on my wrists. Works every time!” – Jamie
 
“Call me crazy, but I like to flip on the air conditioner.” – Trevour
 
“Go for a good, long swim =) A nice way to cool down with an added calorie burn.” – Laura
 
“Quick cold shower before bed, that way I smell pretty for my early morning class too (crazy bed hair is a totally different problem)!” – Julie
 
“Frozen blueberries! It’s a great way to re-energize and is totally refreshing!” – Emily

Have you ever been dehydrated during a workout? What happened and what did you do next time to stay hydrated?