The Dos and Don’ts of Running in the Heat

It's one of the hottest summers on record—but I still need to get outside and exercise. How can I stay cool when I run?


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Lucky for you, there’s been a lot of research into how to stay cool when temperatures rise. We’ve looked into nine popular heat remedies to see whether they’re truly worth the effort.

The Dos and Don’ts of Running in the Heat: Wear Synthetic Clothing

If you have that perfectly distressed cotton tee that you love, wear it. Several studies have shown that there’s little thermoregulatory benefit to wearing synthetic shirts over cotton, though synthetic shirts might be more comfortable.

As for a cotton/polyester hat, you can wear that, too. One study showed that donning a cap won’t make your core temperature hotter than going without—but it can feel hotter. 

Into compression? Even in higher temperatures, you can wear your compression socks. They may lower your perceived rate of exertion without significantly raising your core temperature. 

The Dos and Don’ts of Running in the Heat: Drink a Slushie

Studies have found that drinking an ice slurry before running in the heat can prolong time to exhaustion and lower body temperature during exercise. The recommended amount? About 8g per kilogram of body weight, or about 20 ounces for a 150-pound person.

The Dos and Don’ts of Running in the Heat: Trick Yourself

Believing it’s not as hot out as it is can improve performance by lowering your rate of perceived exertion. In one study, cyclists who were told it was about 79 degrees when it was really 89 degrees rode half a mile farther than cyclists who knew the true temperature, and put out 16 more watts during a 30-minute time trial. This info, of course, won’t help you stay cool. But if you’re worried about performance in the heat, try not checking that weather app before heading out the door.

The Dos and Don’ts of Running in the Heat: Wear a Scarf

It may not actually lower your body temperature, but cooling the neck can help you run farther in the heat. Try adding some useful flair to your ensemble with a store-bought cooling scarf. Don’t want to spend the cash? Make your own by filling up a pantyhose leg with ice and slinging it around your neck.

The Dos and Don’ts of Running in the Heat: Mist Your Face

Fanning and misting the face can reduce an athlete’s rate of perceived exertion. So try bringing a little misting fan with you on your run. If that’s too cumbersome, try squirting some drinking water onto your face while running into the wind. Simple? Yes. Scientific? Sort of.

The Dos and Don’ts of Running in the Heat: Hold Ice Water

In the late 1990s, Stanford University professors debuted a hand-cooling device dubbed the RTX. The gadget was meant to lower core body temperature, essentially by cooling the hands. But several studies have since found that palm cooling, and the RTX, don’t effectively lower core temperature.

The Dos and Don’ts of Running in the Heat: Wear White

If it’s sunny, opt for light colored clothing. In general, dark clothing will absorb more solar radiation, raising your skin temperature. One study found a manikin wearing black clothing had a surface temperature of up to 15 degrees higher than when the manikin wore white.

The Dos and Don’ts of Running in the Heat: Pre-cool

This one’s a maybe. A 2011 study found wearing a cooling vest before running a 10K had no effect on core temperature or rate of perceived exertion. That said, a 2010 study found that wearing a cooling jacket for a total of 30 minutes before running on a treadmill lowered core temperature, heart rate, blood lactate, and increased the total distance run on the treadmill before exhaustion. So if it’s truly hot, and you can take it, you could try sitting around in a cooling vest before heading out. It just might help.

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