During exercise, your muscle contraction is fueled by a process that gives off heat, and your body’s internal temperature rises. Luckily, your body has a mechanism for cooling itself, which involves the evaporation of sweat from your skin. While the cooling mechanism is effective, when your body really has to work to cool itself, it can lead to dehydration. As a result, the cooling process becomes less efficient, and you increase your risk of overheating. To help prevent overheating during your workouts, stay hydrated, exercise during cooler hours, decrease your workout intensity, wear breathable clothing and allow time for your body to acclimatize.
Your hydration level has the greatest affect on whether you’ll overheat during your workout. An adequate amount of fluid allows your body to efficiently cool itself. Taking in fluid before your workout will help your body better control its temperature and increase the volume of your plasma so it can meet cardiac output demands. Two hours before you intend to exercise, take in about 2 cups of water. If your workout is going to be 60 minutes or longer, drink 3/4 to 1 cup every 15 to 20 minutes during your session.
Exercise During Cooler Hours
When exercising in higher temperatures, your body’s temperature will rise higher and more quickly. Adjust your schedule so you can work out in the morning or evening when it’s cooler outside. Harvard Medical School notes that a temperature of 70 degrees or higher adds stress to your body’s cooling system. If temperatures are still high in the mornings and evenings, try to exercise in your air-conditioned house or at the gym.
Lower Your Intensity
When you find yourself having to exercise in hot or humid conditions, decrease your risk of serious overheating by lowering your workout intensity. You'll decrease the cardiac output demands placed on your respiratory system, and your body will use less fluid in the energy-production process so it has more to use for its cooling mechanism.
Wear Breathable Clothing
Keep your body cooler by exercising in light-colored and breathable clothing. Clothes made from a blend of nylon and polyester are lightweight and breathable; they wick away moisture and dry quickly. Cotton fabrics are also breathable but don’t wick away moisture or dry as quickly as the nylon and polyester blends. Dark-colored and heavy clothes will make you even hotter. Anything on your head, such as a workout cap or beanie, traps in heat and will increase your body temperature.
Take Time to Acclimatize
If you live in an area that’s experiencing a heat wave, your body eventually will acclimatize to the weather. To start, exercise at a low intensity and short duration. Gradually increase your workout’s intensity and duration to give your body time to adapt. Your cardiovascular system will naturally decrease your heart rate and increase the volume of your plasma after about three to six days. After nine to 10 days, your body will change your electrolyte concentration and rectal temperature. After two weeks, you should be fully acclimatized. While exercising in the heat still will cause stress, the stress is minimized in an acclimatized body and your risk of heat-related illnesses is reduced.