Working Out in the Dog Days of Summer

The dog days of summer are upon us. I can't remember a summer that has been as hot and sweltering as this one. As much as we all like to get out and enjoy the warmer weather-whether you are running, playing a pickup game of basketball, going for a power walk or a long stroll on the beach, take care when the temperatures rise. If you exercise outdoors in hot weather, use these common-sense precautions to prevent heat-related illnesses.

How Heat Affects Your Body

Exercising in hot weather puts extra stress on your body. If you don't take care when exercising in the heat, you risk serious illness. Both the exercise itself and the air temperature increase your core body temperature. To help cool itself, your body sends more blood to circulate through your skin. This leaves less blood for your muscles, which in turn increases your heart rate. If the humidity also is high, your body faces added stress because sweat doesn't readily evaporate from your skin. That pushes your body temperature even higher.

Heat-Related Illness

Under normal conditions, your skin, blood vessels and perspiration level adjust to the heat, but these natural cooling systems may fail if you're exposed to high temperatures and humidity for too long, you sweat heavily and you don't drink enough fluids. The result may be a heat-related illness. Heat-related illnesses occur along a spectrum, starting out mild but worsening if left untreated. Heat illnesses include:

Heat Cramps: Heat cramps are painful muscle contractions, mainly affecting the calves, quadriceps and abdominals. Affected muscles may feel firm to the touch. Your body temperature may be normal.

Heat Exhaustion: With heat exhaustion, your body temperature rises as high as 104� F and you may experience nausea, vomiting, headache, fainting, weakness and cold, clammy skin. If left untreated, this can lead to heatstroke.

Heatstroke: Heatstroke is a life-threatening emergency condition that occurs when your body temperature is greater than 104� F. Your skin may be hot, but your body may stop sweating to help cool itself. You may develop confusion and irritability. You need immediate medical attention to prevent brain damage, organ failure or even death.

Pay Attention to Warning Signs

During hot-weather exercise, watch for signs and symptoms of heat-related illness. If you ignore these symptoms, your condition can worsen, resulting in a medical emergency. Signs and symptoms include muscle cramps, nausea or vomiting, weakness, headache, dizziness and confusion.

If you develop any of these symptoms, you must lower your body temperature and get hydrated. Stop exercising immediately and get out of the heat. If possible, have someone stay with you who can help monitor your condition. Remove extra clothing or sports equipment. Drink fluids-water or a sports drink. If possible, fan your body or wet down your body with cool water. If you don't feel better within 30 minutes, contact your doctor. If you have signs of heatstroke, seek immediate medical help.

Once you've had heatstroke, you're at a higher risk of getting a heat illness again. Get cleared by your doctor before you return to exercise if you've had heatstroke.

How to Avoid Heat-Related Illnesses

Get acclimated: If you're used to exercising indoors or in cooler weather, take it easy at first when you exercise in the heat. As your body adapts to the heat over the course of one to two weeks, gradually increase the length and intensity of your workouts.

Drink plenty of fluids: It's extremely important to stay hydrated. If you're thirsty then you are already dehydrated; drink before you feel a need to. Be sure to drink throughout the day (stick to non-caffeinated beverages, preferably water.) If you plan to exercise intensely or for longer than one hour, consider a sports drink instead of water. Sports drinks can replace the sodium, chloride and potassium you lose through sweating. Avoid alcoholic drinks because they can actually promote fluid loss. Also, drink 15-20 minutes before beginning your workout and every 15 minutes throughout the exercise.

Eat regularly: The heat can decrease your appetite, but it's important to eat normally. Try to eat small meals five to six times per day. Include lots of fruits and vegetables. Aside from being nutritious, fruits also tend to help with hydration.

Wear light, loose fitting clothes that can breathe: Cotton is always a good choice. If your outdoor activity produces a lot of perspiration, consider clothing that is designed to wick the sweat away.

Wear Sunscreen: Even if you exercise early in the morning or late in the evening, if the sun can reach you then you can get burned. Not only is sunburn bad on the skin and potentially dangerous but sunburn decreases your body's ability to cool itself.

Use common sense: Don't attempt strenuous activities to which your body is not accustomed. Stick to exercises that you are very familiar and comfortable with.

Check the weather forecast: It's best not to participate in intense outdoor exercise sessions when the heat index registers in the dangerous zone.

Understand your medical risks: Certain medical conditions or medications can increase your risk of a heat-related illness. If you plan to exercise in the heat, talk to your doctor about precautions.

What You Should Not Do

Don't Try to Diet by Sweating: Excessive perspiration is not the key to permanent weight loss. Any decrease in the scale would simply be a result of water loss, not fat reduction.

Don't Adopt the "No Pain, No Gain" Motto: Ignoring your body's signals could be dangerous. Heat-related illnesses come with warning signs. Be sure to learn how to recognize them and what actions to take.

Don't Forget to Drink Plenty of Liquid When Swimming: Just because your body is surrounded by water does not mean that you are well-hydrated. As with any land exercises, you need to regularly replenish lost fluids when in the pool.

Avoid Physical Activity During the Hottest Part of the Day, which usually is between 10 a.m. and 3 p.m. If you want (or need) to be working in very hot temperatures, don't do it until you become acclimated. Try to spend only a few minutes per day in the hot conditions for the first couple of weeks and then add time gradually each day.

Avoid Extreme Changes in Temperature: Don't hop from being extremely hot and sweating excessively right into an ice cold, air-conditioned environment. Try to cool your body down slightly before exposing it to the extreme temperature variation.

Whether you have to work outside or do it for enjoyment, following the above tips will help you stay cool and safe during the dog days of summer. Heat-related illnesses are largely preventable. By taking some basic precautions, your exercise routine doesn't have to be sidelined when the heat is on. So, don't spend the season cooped up, get out there and have some fun!