When outdoor temperatures rise (or you move to, or travel to, a hot climate), your heart has to beat faster and work harder to pump blood to the surface of your skin to assist with sweating to cool your body. If your body can’t cool itself enough, strain is put on the heart, and organs can begin to suffer damage - a potentially fatal condition known as heat stroke.
Anyone can suffer heat stroke, but people with heart disease and other cardiovascular diseases are at greater risk. If you have heart disease, your heart may not be able to work harder in the heat to maintain cooler body temperatures. If you have a baby or young child with complex congenital heart disease, try to avoid exposing your child to extremely high temperatures.
Some medications prescribed to patients with heart conditions reduce water in the bloodstream. These medications can reduce a person’s ability to cool off in the heat. If you have been prescribed diuretics or beta-blockers, ask your doctor about safe levels of water to drink for hot conditions versus milder temperatures.
Symptoms of Heat Exhaustion
Heat exhaustion is a form of heat sickness that can lead to heat stroke. The symptoms include:
- Heavy sweating with cool, clammy skin
Symptoms of Heat Stroke
Heat stroke is an emergency. If you experience the following symptoms, apply cool water to your skin immediately and seek medical help.
- High fever
- Hot, dry skin without sweating
- Pounding pulse
- Nausea and/or vomiting
Getting out of the heat immediately, applying cool water to your skin, and drinking cool (not cold) water can help you stop heat exhaustion before it worsens.
Tips for Staying Safe in the Heat
Everyone is at risk in high heat, but the risks are even higher for those with heart disease or high blood pressure. A few simple tips can help you prevent both heat exhaustion and life-threatening heat stroke. Remember, while heat stroke may happen after only a short time in high temperatures, heat exhaustion results from days of exposure to high heat and can progress to heat stroke. Heat waves - long periods of hot weather - can make you ill more slowly and make it harder for you to realize the seriousness of your symptoms. Be mindful of how you feel each day during a heat wave.
Whether it’s a single hot day or a heat wave, remember these tips to stay cool and safe.
- Avoid vigorous physical activity in high heat. No task or exercise program is worth risking your life for. Make plans to complete a task when the weather cools. Move your exercise program to an indoor gym or pool.
- Stay hydrated by drinking water and sports drinks that contain electrolytes. Water is critical to all functions in your body. Electrolytes not only help balance hydration in your body, they also help keep the body’s natural electrical system that governs your heartbeat working correctly.
- Avoid caffeine and alcohol. These beverages can contribute to dehydration.
- Choose a cooler environment. Switch your air conditioning on. If you don’t have air conditioning, use fans and periodically apply cool water to your skin. If your home is still not cool enough, go to an air-conditioned mall, senior center, friend’s house, or library - anywhere that’s cool enough to keep your body temperature within the normal range. Also, if you are not able to leave your home, do not be shy about asking for help from friends, family, or your local town or city services.
- Wear light-colored, lightweight clothing. Light-colored clothing reflects the sun’s rays, rather than absorbing them like dark clothing. Heavy-weight fabrics will trap body heat in, while lightweight fabrics allow heat to escape and better allow for your natural sweating processes to cool you off.
- Don’t go outside without sunblock. Apply sunblock before you go outside. A sunburn can make it harder for your body to stay cool.
Is It Ever Too Hot for Your Heart to Exercise?
When the temperature reaches 70 degrees Fahrenheit (21 degrees Celsius) and the humidity is 70 percent or higher, your heart has to begin to work harder just to cool your body. When the outdoor temperature climbs into the 80s (Fahrenheit) or high 20s (Celsius) or beyond and there is high humidity, the risk to your health also rises. If you have heart disease, it is especially critical that you avoid exercising when the temperature and the humidity are both high. Consider delaying any intense exercise until the temperature has dropped and the humidity has reduced, or consider doing your doctor-approved exercise where the weather won’t be a problem, such as in air conditioning or in a swimming pool.
Another important issue to consider when planning your exercise for the summer months is that some common heart medications, such as beta blockers and diuretics, can also make you more susceptible to heat. Ask your doctor about summertime exercise guidelines that make sense for you based on your medical history and current prescribed medications.