Posted on: August 15, 2008

When the Heat is On

Extreme temperatures and exertion leave many people dangerously overheated – here’s how to keep your cool

By Jeff Schnaufer
CTW Features

Image courtesy Mike Reisel

How dangerous is overheating during the summer? Consider this not-so-sunny statistic: From 1979 to 2003, more people (8,015) died from extreme heat than from hurricanes, lightning, tornadoes, floods and earthquakes combined.

“Heat-related deaths and illness are preventable, yet annually many people succumb to extreme heat,” says Dr.George Luber, extreme heat expert for the Centers For Disease Control and Prevention, Atlanta, who provided the numbers above.

While no one, from children to the elderly, is exempt from the dangers of excessive heat exposure, athletes and those who exercise regularly need to be particularly careful while working out in the sun. In organized athletics, exertional heat stroke causes between one to five deaths per year, mostly in high school sports, says Brendon P. McDermott, MS, ATC, University of Connecticut and member of the National Athletic Trainers Association (NATA)

“We have heard of exertional heat stroke deaths in individuals as young as 11,”McDermott says.

Heat stroke is the most dangerous heat related illness, though athletes may also encounter heat exhaustion, heat cramps and heat rash. Luber says warning signs of heat stroke may include red, hot and dry skin; a strong and rapid pulse; body temperature above 103 degrees; inability to sweat; and headache, dizziness, nausea and confusion. Sometimes, McDermott cautions, exertional heat stroke can strike without any warning.

To avoid overheating your body’s engines while exercising this summer, McDermott offers these tips:

1. Gradually increase activity in terms of intensity and duration in the heat. This prepares your body for more intense, longer duration exercise in warm conditions, and helps prevent injury and heat illness.

2. Intersperse periods of rest during activity, and assure adequate rest between exercise bouts. Rest breaks are an important defense against heat illness, and proper sleeping habits decrease your risk as well.

3. Begin outdoor activities only after you’re properly hydrated. Drink water or sports drinks throughout physical activity in the heat. Weight maintenance (neither a gain or loss) over the course of a single 24-hour period is a decent measure of hydration status. A darker urine color is another quick indicator of dehydration. Your urine should look more like lemonade than apple juice.

4. Exercise during cooler portions of the day (early morning or late evening), if possible.

5. Do not participate in intense exercise if you show signs an existing illness (i.e. fever, stuffy nose, diarrhea, extreme fatigue, etc.). These can decrease your body’s tolerance for heat and increase your risk of a heat illness. Back off on exercise intensity or duration if not feeling well (i.e. walk instead of run, cut the session short, etc.)

Finally, McDermott says, consider scaling back or eliminating exercise in some situations.

“In extremely hot conditions, high intensity exercise, either intermittent or long duration, should be avoided,” McDermott says.

When it comes to scaling back exercise, McDermott says, “The intensity is personal. If you’re used to running ten 5-minute miles per day and it’s a hot day, you’d probably scale back to run seven 6-minute miles that day. If you normally walk 3 miles at a moderate pace and it’s a hot day, you’d scale back to walk 2 miles at an easy pace and incorporate a break at the halfway mark. Exercise to avoid is anything above and beyond what you’re used to. It’s not a good idea to ramp up exercise to a new level during the hottest day of the year.”