For weeks, residents of the Pacific Northwest and other western states have been experiencing hot summer temperatures that are way above normal, and there’s no relief in sight. Rising well above 100 degrees Fahrenheit in some areas, people have been staying in hotels or jumping in pools to deal with the heat, since many don’t have air conditioning. For exercise enthusiasts, it can make things uncomfortable to say the least.
As the Centers for Disease Control and Prevention (CDC) reports, as you age, your chances of being hospitalized or even dying from heat-related illness go up exponentially. That’s why, whether you’re exercising or not, it’s best to take precautions before heading outdoors in high summer temperatures.
But if the idea of a run in the sun or a bike ride in balmy conditions sounds glorious, read on for safety measures you should take, according to two experts.
What to know about heat and humidity
While heat alone can certainly pack a wallop, it’s heat and humidity that can truly put a damper on your workout.
“What you really want to try and avoid is heat and humidity,” says Steve Stonehouse, NASM CPT, USATF, Certified Run Coach and Director of Education for the STRIDE franchise. “The combo can be dangerous because in heat, you’ll sweat to cool off, but the humidity makes it difficult for the sweat on your skin to dry.”
Dr. Nandini Collins, Noom Senior Health Coach Manager, adds that it’s key to pay attention to the heat index, which combines air temperature and relative humidity, as a good indication of caution for taking workouts outside.
She says, “For instance, the temperature may simply say 84 degrees, but when combined with humidity, it can bring the heat index to well over 90 degrees. If the heat index is 90 degrees or above, it becomes harder for the body to cool since sweat can’t evaporate as efficiently. Since the body’s goal is to maintain its temperature close to 98.6 degrees, it is prudent to use extreme caution when exercising outdoors in the heat to minimize illness and injury.”
While it’s imperative to heed these numbers, it’s also important to think about yourself as an individual: your abilities, your fitness level, and your tolerance to heat. The ability to exercise in the heat can vary greatly from person to person.
Dr. Collins says that some runners argue that their muscles are already warm in the heat, so there is less of a chance of injury. She adds that interestingly, many asthmatics respond better to heat and humidity in terms of breathing, whereas others struggle in the heat more than in colder temperatures.
It comes down to one thing: Acclimating in the heat before revving up your workout.
She explains, “Provided there is a proper acclimatization period, exercising in the heat can actually benefit those who prefer outdoor activities. Proper acclimatization is the key. Without acclimatization, most athletes should consider that the risk of illness and injury is higher when exercising in the heat, and they should opt for an indoor workout.”
How to exercise in high temperatures
Just like acclimating to those climbing temps, it’s essential to take other precautions as well, to ensure your safety and to have the best possible workout you can. The first place to start? Drinking good ol’ H2O.
Dr. Collins says, “Make sure you are well-hydrated before, during, and after you exercise outdoors in the heat, making sure to drink more water than usual. Many athletes like to supplement with sports drinks in moderation to replenish potassium and electrolytes.”
Also, think about the timing of your workout. Try to avoid the hottest part of the day, which is typically the afternoon, and aim for some early-morning exercise or move your workout to the evening.
Consider taking a cold shower before your workout and leave your hair wet as well.
Stonehouse says that it’s helpful to “dress appropriately,” and Dr. Collins says this involves wearing lighter-colored clothing—it’ll be a bonus if has sweat-wicking, sun-protective UPF fabric that reflects the sun—and expose enough skin to evaporate liquid while wearing sunscreen.
Lastly, Stonehouse emphasizes how crucial it is to listen to your body. This means taking breaks when needed and, as Dr. Collins advises, modify your exercise duration and intensity, knowing that your body won’t be able to cool itself as efficiently at a high temperature.
Related: The Importance of Proper Hydration
When to stay indoors
For many, exercise performance shouldn’t be affected by toasty temperatures if you’ve taken the time to hydrate and gotten acclimated to the heat. But in extreme heat, Dr. Collins says that performance will likely be altered for most individuals. In that case, exercise should be done indoors.
But let’s say you’re already halfway into your sizzling run when you aren’t feeling so great. There are certain warning signs of heat illness you can look for.
“When you stop sweating, it can get bad quickly,” Stonehouse cautions. “If this happens, I’d suggest stopping exercising and immediately get as much fluid in as you can.”
On the flipside, Dr. Collins says that excessive sweating can also be a symptom. She details additional signals that a person should stop exercising in the heat, which include:
- Shallow breathing
- Fast or slow irregular heartbeat
She adds that if any of these warning signs are present, one should:
- Drink cool, nonalcoholic beverages
- Stop activity and rest
- Take a cool shower, bath, or sponge bath
- Seek an air-conditioned or cooler environment
- Wear lightweight clothing
And of course, if you know that you aren’t functioning well at all, you can always visit the emergency room for medical attention.
“While it may be tempting to get a little more sweat on and burn extra calories in the heat, one should use caution when deciding to exercise outside in extreme temperatures,” Dr. Collins says. “Dehydration, heat exhaustion, and heat stroke are just a few of the heat-related illnesses that can occur. Listen to your body and work out smarter, not harder.”
Again, it’s vital to know yourself and your body well before braving those high temperatures.
Stonehouse adds, “Some people may have an easier time dealing with extreme temperatures simply because of where they’re from or what they’ve become acclimated to, but for most, there’s no genetic set-point limiting them in certain temperatures over others.”
At the end of the day, it’s really up to you and your heat tolerance if you decide to take your summertime workouts in the heat of the outdoors.