With shorts and swimsuit season here, many of us get more active as we try to shed the unwanted weight we may have gained during the cold weather months. We begin new running or walking routines or we start to do outdoor activities such as biking and tennis.
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If you have heart issues, be sure to talk to your doctor before starting a routine – especially in the warm weather. But whatever our usual activity level is, exercising during the hot summer months should be approached with a little planning.
Why? Because the combination of exercise, the humidity of summer days and the bright, warm sunshine increases stress on our hearts. For every degree the body’s internal temperature rises, the heart beats approximately 10 beats per minute (bpm) faster. And as the heart works to provide blood and oxygen to the exercising muscles, it must also work to route blood to the skin where it can be cooled by the evaporation of our sweat.
Exercise and higher body temperatures plus the added work of cooling can dramatically increase stress on the heart during exercise in the heat and humidity of summer.
If you are a heart patient, overweight, diabetic, on a medication in the Beta-blocker group or over the age of 50, you want to be especially mindful of the following pointers (after talking with your doctor first). Tips for exercising in the heat:
- Minimize the stress of the heat by exercising in the cooler morning or evening hours. And on especially hot and humid days, it is best to slow your normal exercise pace too.
- If the temperature is above 80 degrees and the humidity is above 80 percent, it’s best to postpone outside activity until things cool off.
- Monitor your exercise heart rate and stay within the appropriate ranges for your age and weight. An exercise physiologist or rehabilitation therapist can help you adjust your exercise level for the added thermal load and avoid overtaxing the heart.
- Stay hydrated. If you plan to exercise for 30 minutes or more, maintain your fluids. Drink 8 to 12 ounces of water 20 to 30 minutes prior to exercise and 6 to 10 additional ounces for every 30 minutes of exercise to prevent dehydration. If you have heart failure or fluid restrictions, talk to your doctor first before following these recommendations.
- Track your weight change with each acute activity. If your weight drops by more than 3 percent with an exercise session below your normal pre-exercise level you are at risk of dehydration, decreased exercise capacity and compromised cardiovascular function. For every 2 pounds lost with an acute exercise bout, the body requires approximately 1.5 quarts of fluid to replace the lost water weight.
- If you plan to exercise for more than an hour, sports drinks may be added to your liquids. In most cases, water is enough. However, if you are exercising at high intensity, you will lose electrolytes in that amount of time, and you may need the sodium and calories that sports drinks provide. (Patients with diabetes or sodium restrictions need to read labels to find the best option for less sugar and sodium drinks.)
- And remember to dress for the temperature and the activity. Sweat-suits and long sleeves will prevent evaporation of sweat and interfere with the body’s ability to cool itself. This can raise body temperatures to dangerously high levels. Wear loose-fitting cotton t-shirts, shorts and a brimmed hat when exercising outside in the summer.
“Be heart-smart, stay active and reap the benefits of regular exercise all year round,” recommends Gordon Blackburn, MD, Director of Cardiac Rehabilitation, Preventive Cardiology and Rehabilitation Program at Cleveland Clinic. And if it’s too hot outside, you can always try walking inside in a mall or even a large store.
Learn more about exercise and heat – http://my.clevelandclinic.org/heart/prevention/exercise/exandheat.aspx