Exercising outdoors in the summer can be exhilarating, and training in the heat is beneficial for serious athletes. But running in high temperatures also carries some risks of heat- and sun-related illnesses. Runners can stay fit and enjoy summer exercise in safety by keeping some essential tips in mind.
Running before the sun rises over the horizon is one way to avoid the worst of the summer heat. Areas with high humidity might not cool down after sunset, making mornings the coolest, but in dry regions, it tends to get much more comfortable in the evening. Remember to take safety precautions — like reflectors, lamps, or light-color clothing — if you’re running in the dark.
It makes sense to dress lightly when it’s hot outside, and choosing the right fabrics can make a big difference. Runners should avoid wearing cotton — it soaks up sweat, and the wet fabric sticks to the skin, trapping heat. Workout clothing made from technical fibers, usually synthetic, directs moisture away from the skin, which helps the body cool down. Loose-fitting clothes with some texture also help keep the fabric from clinging and preventing heat from escaping.
The human body adapts to the heat, but it takes at least seven days. Plan to run a little slower and for shorter distances than usual until the body adjusts to these new demands. When a person’s core body temperature goes up, energy is diverted to sending blood to the surface of the skin, expanding capillaries in preparation for heat release. That is energy that the body will not have available as a fuel source for the run.
Drinking water helps runners produce enough sweat to stay cool. It’s essential to pre-hydrate, especially for long runs on hot days. A guideline from the American College of Sports Medicine is to drink about 16 ounces of water two hours before a run. That gives time to visit the bathroom before heading out. Drinking water during a long run is important, too. Drink cool rather than ice-cold water; the body absorbs cool water faster.
Too much sun exposure increases the risk of serious eye issues, like cataracts and eye cancer. The sun’s rays are strongest in the summer, and sunlight reflects off the pavement and other surfaces. Outdoor exercisers should look for sunglasses that provide 99% UVA and UVB protection. Wearing a visor or cap while running outdoors is also helpful for providing some extra shade for your eyes and face.
Most skin cancers are caused by exposure to the sun’s UV rays, according to the American Academy of Dermatology. Even short runs can be risky for sunburns when the UV index is high. Runners should choose a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 30. It should be applied 15 to 30 minutes before heading outdoors and reapplied every two hours.
Runners can stay safer in the heat and perform better by cooling off mid-run. One way to do that is to pour cold water over the head. If time is not of the essence, such as during a long training run, taking periodic plunges into a pool can help a runner keep going without overheating. Some marathoners start out races with ice-cubes packed under their hats or in plastic bags around their necks.
If it is not possible to run before or after the heat of the day, seek shady trails or run inside on a track or treadmill. People used to running outdoors often find treadmill exercise boring, but using it to run intervals or alternating 10 minutes on the treadmill with 10 minutes outdoors can help break up the tedium.
It is not necessary to get exercise in all at once to reap its benefits. On hot days, runners can make it easier on themselves by breaking up runs into two 15-minute sessions or three 10-minute sessions, for example. Studies show that short bouts of exercise spread throughout the day improve cardiovascular fitness and assist in weight loss, just like continuous workout sessions do. So, running 15 minutes before work and 15 minutes after has comparable benefits to running 30 minutes all at once, but a lower risk of heat adversity, since the sessions are shorter.
When it is very hot outside, taking a day off and cross-training might be the best bet. Some situations or conditions also make people more sensitive to heat, such as taking diuretics or blood pressure medication. People who have a medical condition or are generally unfit should check with their doctor before running in summer weather.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.