After exercising inside all winter (or, you know, lounging on couch), you might have a wicked case of cabin fever by the time summer rolls around. A gorgeous, sunny day is the ultimate motivation to take your workout into fresh, open air. From running to cycling, there are a ton of outdoor activities that beckon. But the summer heat and vigorous exercise can be an unsafe combination if you don't take the proper precautions.
Risks of Exercising in the Heat
Summer heat can be hard on your body, especially during exercise. That's because all your systems are working overtime to keep you cool. When temperatures and humidity soar, you produce more sweat, which can result in dehydration, electrolyte imbalance and heat-related illnesses, says Natasha Turner, founder of Clear Medicine Wellness Boutique and author of The Supercharged Hormone Diet.
Muscle cramps and spasms might be the first sign you're overheating and experiencing a heat-related condition like heat exhaustion. Other symptoms include nausea, vomiting, weakness, headache, fainting, increased sweating and cold, clammy skin.
If you stop sweating but still feel confused and disoriented and have a core body temperature above 104 degrees Fahrenheit, you could be suffering from heat stroke. The most dangerous heat-related illness, heat stroke happens when your body's temperature control system fails.
If you suspect you have heat stroke, seek medical attention immediately. “It’s important to get cool ASAP,” says Turner. “Immerse yourself in cool water, drink cold fluids and put ice packs on your neck.”
Tips for Exercising Safely in the Heat
Even though working out in the summer heat should be approached with some caution, you can still enjoy the benefits of exercising outdoors with a little planning. Here are a few tips to keep you safe while having fun in the sun.
1. Stay Hydrated
Since you lose a lot of fluids through excessive sweating, you'll need to replenish with water. "Hydration is key," says certified personal trainer Ava Fagin, who recommends drinking eight to 12 ounces of water prior to exercise. "The more hydrated your body is, the more it will be able to adapt to the stress of heat."
To estimate how much H20 your body needs, multiple your weight by 0.55, then divide by eight. This is the number of cups you should drink per day, says Turner, who suggests tacking on two to four additional cups when exercising in the heat.
And don't wait for your "thirst signal" to appear. Sip water continuously — at least every 15 minutes — to ensure you stay properly hydrated in hot weather. Turner recommends drinking room temperature water, since it's more easily assimilated into the body. "Ice cold water has to be heated up first before it can be absorbed and beneficial for hydration," she says. But any water is better than no water.
2. Replenish Your Electrolytes
In addition to water, you're also losing electrolytes like sodium, magnesium and potassium when you sweat, says Nedra Lopez, personal trainer and owner of The P.E. Club. Since electrolytes are crucial to your body's healthy functioning, you need to make sure they remain properly balanced.
How can you tell if your electrolytes are off? If you're losing steam, getting cramps, feeling dizzy or your blood pressure is low, you might be experiencing an electrolyte imbalance. Or pinch the skin and let it go, says Turner. "If it stays raised up, you're likely dehydrated and in need of sodium and water."
Don't reach for sports drinks, though, as they tend to be packed with sugar, high fructose corn syrup and artificial sweeteners. Instead, opt for a quality electrolyte supplement (like Liquid I.V., LyteShow or Hi-Lyte) to help your body replenish and repair after vigorous exercise. You can also sprinkle a tiny amount of Celtic sea salt (less than a quarter of a teaspoon) on your food. Just don't dissolve the salt in water, which may cause you to feel nauseated, says Turner.
3. Avoid the Hottest Part of the Day
To minimize stress on your body, it's wise to avoid the sun at peak hours, says Lopez. If it's an extremely hot day, it's best to exercise in the morning or the evening when it's cooler. Try to find a shaded area where you can avoid direct sunlight. This will help you stay cool and keep your body temperature and heart rate from soaring to an unsafe point, says Fagin.
But if the mercury rises above 80 degrees Fahrenheit and the humidity increases to more than 80 percent, you're at a greater risk for heat-related illness, so you're best off taking your routine indoors for the day and savoring a safe, air-conditioned environment.
4. Wear Sunscreen
If you can't avoid the sun, you need to protect yourself from harmful UV rays. Not only does sunburn hurt, it also affects your body's ability to cool itself, which can be dangerous when exercising in intense heat. Need more reasons to wear sunscreen? It helps prevent against skin cancer and premature aging, duh!
Apply a broad-spectrum sunscreen that shields you against both UVA and UVB with SPF of 30 or greater. Better yet, choose a mineral-based one with zinc oxide or titanium dioxide, two minerals that were recently deemed the only safe and effective sunscreen actives by the Food and Drug Administration. And don't forget to reapply at least every two hours (more often if you're sweating profusely or swimming) even if the label claims the product is "water-proof."
Read more: The 27 Safest Sunscreens and 3 to Avoid
5. Slow Down
When you exercise outside in the dead of summer, you fatigue faster than usual. Even a light, easy routine on a recovery day might feel grueling in the hot weather. That's because your body's working doubly hard. Not only does it have to pump blood to your active muscles, but also to your skin to keep you cool.
Listen to your body and know when it's time to ease up a bit. "Lower the intensity of your regular routine in the beginning until your body adapts to the heat," says Lopez. For example, if you normally run, slow your pace to a jog, shorten your distance and take frequent water breaks.
As you adjust to the weather, your body will become more conditioned, and gradually, you'll be able to increase your intensity. "It may take a week or two before you can push yourself to the next level safely," says Lopez. So, give your body time. Slow and steady wins the race.
6. Monitor Your Heart Rate
Exercising in the heat accelerates your heart rate. That's because warmer weather increases the demands on your ticker, which must pump more blood throughout your skin to regulate your body temperature.
And the hotter it gets, the more stress there is on your heart. In fact, for every degree the body's internal temperature rises, the heart beats about 10 beats per minute faster, according to the Cleveland Clinic.
Monitoring your heart rate is a good way to ensure you're not overtaxing your cardiovascular system, says Fagin. To estimate of your max heart rate (MHR), subtract your age from 220. For example, a 30 year-old adult's MHR would be 190. "Typically, you want to stay within 55 to 85 percent of your MHR," says Fagin. If you take medication or have a health condition, discuss your safe target heart rate zone with a medical professional.
Pay attention to your body. If you feel dizzy or faint, you might be overloading your heart. Get to a cool place immediately and hydrate.
7. Try Water Workouts
Nothing's more refreshing than a dip in a pool on a sweltering summer day. Swimming and other water-based workouts not only keep you cool, but also burn calories and build muscle thanks to the resistance of the water.
Aquatic exercise is also a great, low-impact alternative to land-based aerobic and cross-training workouts. Since they're easier on your joints, water workouts are great for active recovery days or if you're rehabbing an injury. As an added bonus, water-based exercises have positive effects on pain, physical function and quality of life, according to a 2014 study in the Archives of Physical Medicine and Rehabilitation.
Read more: 7 Tips to Become a Better Swimmer
8. Wear Light-Colored, Lightweight Clothing
Your workout clothes can make or break a summer workout. Since the goal is to stay as cool as possible, toss the tight-fitting tops and bottoms. "Our bodies naturally cool through the process of perspiration and evaporation of sweat from our skin, and tighter clothes prevent sweat from evaporating," says Fagin.
So, keep it loose. Choose breathable, lightweight clothes that let the air flow around and through you. And stick to light colors. Dark colors absorb and trap the heat. For an extra refreshing blast of cold, Turner suggests wearing a cooling bandana around your neck. Made of drip-free, hyper-evaporative fabric, dunk one in icy water for long-lasting cooling effect.