Hot weather exercise
04:24 - Source: CNN
CNN  — 

There is nothing quite like an alfresco workout, with its fresh air and changing scenery. But when temperatures soar, beware.

Exercising in hot weather stresses your body, especially if the humidity is high. If you do not take proper precautions, it can actually be dangerous, and potentially lethal. The number of heat-related deaths while participating in sports has doubled in the United States since 1975, according to the National Institutes of Health. And the US Centers for Disease Control and Prevention reports that some 650 people die from extreme heat every year.

So if you are planning to head outside when the temperature is climbing, keep these tips in mind.

Important note: Before beginning any new exercise program, consult your doctor. Stop immediately if you experience pain.

Watch the time of day

You may love exercising over the noon hour, but that’s a terrible time to head outside when it’s hot. No matter what climate you are in, schedule your workouts for early morning or evening, when heat and ozone levels are lower. And definitely do not go out between 10 a.m. and 3 p.m., when the sun is overhead, and temperatures are at their peak.

Know your risk level

Risk factors for heat-related illness include age (4 and under and 65+), obesity, high blood pressure, heart disease, mental illness, diabetes, and prescription drug and alcohol use. Where you are working out may be a factor, too; the bulk of heat-related deaths in the US occur in Arizona, California and Texas, according to the CDC. Knowing your fitness level is also important. If you are out of shape or new to exercise, you may be more prone to heat issues.

Dress properly

Wear loose, lightweight and light-colored clothing to help keep the heat at bay. Add a light, broad-brimmed hat and sunglasses, if possible. Do not forget the sunscreen – which you should regularly reapply – as a sunburn can be dehydrating, plus it hampers your body’s ability to cool down.

Acclimate to the heat

Just as you need to acclimate your body to a higher elevation, you also need to help your body adjust to the heat, especially if you normally exercise indoors or in cooler weather. Acclimate by shortening your workouts and lowering their intensity for a week or two once it’s consistently hot outside.

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Stay hydrated

Being well hydrated is key to preventing heat illness, whether you are exercising outside or sitting around indoors. So keep tabs on your hydration level at all times. The CDC recommends drinking eight ounces of water every 15 to 20 minutes when you are out in the heat.

To achieve this, carry water with you and drink regularly, even if you are not thirsty. For once you find yourself thirsty, you are already at least slightly dehydrated. If you struggle to down water, try a sports drink instead. Or eat some fruit.

“Drinking water isn’t the only way to stay hydrated,” said Stephen Phillips, a certified personal trainer at Atlanta’s Berman Center, a mental health and substance abuse treatment facility. “Eat more foods that are full of water, like cucumbers and watermelon, either beforehand or during the workout.”

Get creative

Take a cool or cold shower before working out to help your body stay cooler for a longer period of time. You can also use a hydration pack, said Tom Gil, a certified real estate copywriter and marketing consultant who once trained in the scorching Jordan Rift Valley as a member of the Israeli Special Forces.

“They help by having cold water lean against your body, lowering its temperature, and they have a long straw reaching your mouth,” which helps you hydrate quickly and easily, said Gil via email.

Pace yourself

Even if you have acclimated to the heat, are hydrated, and have the proper clothing and gear, you still need to pace yourself. Do your interval training at a slightly slower pace than normal, shorten your workouts and take regular breaks in the shade. If you are struggling at all, or if temperatures hit 90 degrees Fahrenheit, Gil recommended heading indoors.

“When temperatures reach 32 Celsius or 89.5 Fahrenheit – all heavy military workouts, drills and combat simulations stop,” he said. “The Israeli military learned it the hard way – losing soldiers to heat strokes in training.”

Know the signs of heat distress

Symptoms of heat-related illness include muscle cramps, nausea or vomiting, weakness, fatigue, headache, excessive sweating, dizziness, confusion, irritability, visual problems and increased heart rate. If you experience any of these, stop exercising immediately, get out of the heat and hydrate. Once in the shade and drinking water, wet a towel or bandanna and place it on your neck, forehead and underarms. If you do not feel better after 20 minutes, head to urgent care.

Use the buddy system

When the temperature soars, grab a friend to work out with you. That way, you can monitor each other for heat distress. Sometimes too much heat can cause confusion, so you may not realize you are struggling. But your buddy may be able to spot your distress and help get you to safety.

Melanie Radzicki McManus is a freelance writer who specializes in hiking, travel and fitness.