This column presents four strategies forexercising in the summer heat. One criticalconsideration is that regardless of fitnesslevel—novice walker to elite marathoner—everyone must slow down and allow the body to adapt to the heat and humiditybefore returning to their normal training.
Here’s how to exercise safely when themercury rises:
1. Respect the Heat and Humidity
Heat and humidity combined are a serioustest of the body’s ability to deal with heatstress. Heat with low humidity is less of aproblem. Evaporation and cooling can occurwhen the humidity is low, but high humidityprevents sweat from evaporating, and thus,no cooling. With initial exposure to a hot andhumid environment, blood flow is increasedto the skin—the reason that skin can take ona red appearance. In addition, perspirationincreases in an effort to rid the body of theexcess heat built up during exercise from theacceleration in metabolism.
2. Drink Up!
Depending on the intensity of the exercise,fluid intake should be about 12 to 24 ouncestwo to three hours before exercise and about5 to 10 ounces for every 15 to 20 minutes ofexercise. But be cautious about overloadingwith water or other fluids that are low inelectrolytes during extended periods ofexercise. There was a recent report of criticalillness and even death in marathon runnerswho suffered low blood sodium levels from“water intoxication.” Consult your diabetescare team to see if you should be consumingsports drinks with electrolytes (either regularor “lite” versions) during endurance exercise.If your diabetes treatment includes insulinor oral medications that can lower bloodglucose levels, your exercise plan will need toinclude carbohydrates as well.
3. Dress to Stay Cool and ProtectedFrom the Sun
Your clothing should be light in color andmade of “wicking” synthetic fabrics (suchas CoolMax, Drylete, Dri-Fit) designed forathletic activities. Be sure to wear a hat or avisor to protect your face, ears and neck fromthe sun. Sunglasses with UVA/UVB protectionnot only shield you from glare, they alsoprotect your eyes from the sun’s damagingrays, which can lead to cataracts. Dress lightlybut protect your skin from sun, and coverexposed skin with a dermatologist-approvedsweat-proof and rub-proof sun block of SPF15 or 30.
4. Watch for ‘Bad’ Symptoms
Symptoms of hyperthermia include light-headednessand disorientation that mayprogress to loss of consciousness. Treatmentis to stop exercise at once, get into a coolor shady place, and try to cool the body asquickly as possible. Staying fit can preventheat-related illnesses. For people withdiabetes, certain medications and conditionscan prevent their bodies from adjustingproperly to the heat. Consulting with yourcare team can help you decide if exercisingin challenging environmental conditionsis right for you. Working out in climate-controlledenvironments such as at a gym ora swimming pool can help you stay with yourprogram during the hottest days of summer.
Be sure to exercise safely this summer, havefun, and we’ll see you “on the go”!
How Does the BodyAcclimatize to the Heat?
Acclimatization or adaptation to exercisein the heat takes about seven to 14 days to occur.Changes include increased blood volume, so thatwhen the blood shifts to the skin to dump excessheat from exercising, there is less of a strain onthe cardiovascular system. Sweating also occursearlier, and the sweat is less “salty,” resulting inan increased ability to maintain body fluids.