Protect Your Heart in the Heat

friends on a walk

Whatever brings you outside — a bike ride with friends, a jog in the park or just a stroll around the block — it’s important to stay safe when the temperature rises.

Tips for heart patients

If you’re a heart patient, older than 50 or overweight, you might need to take special precautions in the heat, according to Gerald Fletcher, M.D., professor of medicine at the Mayo Clinic, in Jacksonville, Fla.

Check with your healthcare professional before starting an exercise routine if you are experiencing symptoms or have a specific medical question or chronic disease. Certain heart medications like beta blockers, ace receptor blockers, ace inhibitors, calcium channel blockers and diuretics (which deplete the body of sodium) can exaggerate the body’s response to heat, Fletcher said.

But Fletcher points out that it’s important to keep taking your medications —and taking them when you’re supposed to.

Even if they’re not on medications, older people also need to take precautions in the heat.

“If you’re older than 50, you may not be aware that you’re thirsty,” Fletcher said. “If you’re going to be outside, it’s important to drink water even if you don’t think you need it.”

Tips for everyone

Think you’re ready to brave the heat? Watch the clock and buddy up, Fletcher said. It’s best to avoid the outdoors in the early afternoon (about noon to 3 p.m.) because the sun is usually at its strongest, putting you at higher risk for heat-related illnesses.

If you can, exercise with a friend, because it’s safer — and more fun — to have someone at your side. Here are some other tips:

  • Get off on the right foot. You probably sweat the most in your shoes, so choose well-ventilated shoes and look for socks that repel perspiration. Foot powders and antiperspirants can also help with sweat.
  • Dress for the heat. Wear lightweight, light-colored clothing in breathable fabrics such as cotton, or a synthetic fabric that repels sweat. Add a hat and/or sunglasses.
  • Drink up. Before you get started, apply a water-resistant sunscreen with at least SPF 15, and reapply it every two hours. Stay hydrated by drinking a few cups of water before, during and after your exercise. Avoid caffeinated or alcoholic beverages.
  • Take regular breaks. Find some shade or a cool place, stop for a few minutes, hydrate and start again.

Whatever you do, don’t throw in the towel, Fletcher said. “Don’t NOT exercise — adapt!”

Symptoms of heat exhaustion:

  • Headaches
  • Cool, moist skin
  • Dizziness and light-headedness
  • Weakness
  • Nausea and vomiting
  • Dark urine

If you experience these symptoms, move to a cooler place, stop exercising and cool down immediately by using cool wet cloths, compresses, and fanning. You may need to seek medical attention.

Symptoms of heat stroke:

The symptoms of heat stroke include (call 911 or the local emergency number right away):

  • Fever (temperature above 104 °F)
  • Irrational behavior
  • Extreme confusion
  • Dry, hot, and red skin
  • Rapid, shallow breathing
  • Rapid, weak pulse
  • Seizures
  • Unconsciousness

If you experience these symptoms, seek medical attention right away.

Written by American Heart Association editorial staff and reviewed by science and medicine advisors.

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Last Reviewed: Jul 31, 2015