Summertime sports and exercise: How to keep cool in hot weather


Summer sun means summer fun — and sometimes summer hazards.

In the excitement of a good pickup basketball game or even a leisurely game of golf, you might not notice the temperature rising. But as the day progresses, your body notices the heat, and if you don't watch out, you can get into trouble quickly.

Under normal conditions, your body's natural control mechanisms — skin, blood vessels and perspiration — adjust to the heat. But those systems could fail if you're exposed to high temperatures for prolonged periods.

How hot weather affects your body

Exercising on hot days puts extra stress on your cardiovascular system. Both the exercise itself and the air temperature increase your body temperature. To dissipate heat, more blood circulates through your skin. As a result, less blood is available for your muscles, so your heart rate during exercise is higher than on cool days. If the humidity is high, your body faces added stress because sweat doesn't readily evaporate from your skin. So your body temperature rises.

Working out in hot or humid conditions can overstress your body's temperature-regulation system, resulting in an excessive increase in body temperature. Heat-related problems may include heat cramps, dehydration, heat exhaustion and heat stroke.

Heed the warning signs of heat exhaustion and heat stroke

Stop exercising immediately if you experience signs and symptoms of these heat-related problems.

Heat exhaustion. Signs and symptoms of heat exhaustion include cool, clammy and pale skin, heat cramps, a weak pulse, nausea, chills and dizziness, weakness, or disorientation. You may have a headache and be short of breath.

Heat stroke. This condition can be life-threatening. Your skin becomes hot, flushed and dry. You stop perspiring and your body temperature may rise above 106 F. You may feel confused and may even faint.
At the first hint of any of these signs and symptoms, get out of the heat, drink fluids, elevate your feet above your head, and either wet and fan your skin or immerse yourself in cool water. Also, seek medical help.


Heat cramps

Heat cramps are painful muscle spasms that can occur as a result of strenuous physical activity in a hot environment. They develop when sweating depletes your body of salt (sodium) and water. The muscles of your arms, legs and abdomen are most commonly affected.

Heat cramps may also be a symptom of heat exhaustion. Stop exercising if you get heat cramps. Sit quietly in a cool, shady area and drink clear juice or a sports beverage. Don't exercise again until a few hours after the cramps have stopped.

Guidelines for working out in hot weather

To avoid heat-related conditions:

Drink enough fluids. Your body's ability to sweat and cool down depends on adequate rehydration. During heavy exercise in the heat, you can lose almost 2 quarts of water every hour. Recommended fluids include water, sports drinks and diluted fruit juices. Avoid caffeinated beverages such as coffee, tea and cola, which speed the excretion of water from your body.
Sports drinks include electrolytes — sodium, chloride and potassium — which are lost through sweating. If you're going to be exercising very intensely or for longer than one hour, you may benefit from fluids containing carbohydrates and electrolytes. Keep in mind that you can't rely on your thirst to signal how much fluid you need to drink. Your thirst mechanism underestimates fluid loss in the heat.

Wear light-colored, loosefitting clothing made of breathable fabric. Dark or nonporous material can increase your temperature and reduce evaporation. Clothing made with polypropylene can help wick moisture away from the skin. Avoid heavy, rubberized clothing, which can be dangerous in any weather. Loosefitting clothing lets more air pass over your body, providing for sweat evaporation and cooling. A light-colored hat or cap can limit your exposure to the sun.
Exercise in the early morning or late evening. These are cooler times. If possible, exercise in the shade.
Wear sunscreen. Sunburn decreases your body's ability to cool itself.
Allow yourself time to get used to higher temperatures. Your body will gradually adapt to the heat, allowing you to exercise with a lower heart rate and lower body temperature. If you're reasonably fit, allow four to five days to get used to higher temperatures. If you live with a chronic health condition or are older, you may need up to 10 to 12 days to adjust. Shorten the length of your exercise routine, lower the intensity, and gradually increase your effort.
Talk to your doctor if you have a chronic medical condition or take medications. Find out if your condition or medication might affect your ability to work out in hot weather. Certain medications — such as diuretics and antihistamines — may make you more susceptible to heat-related illness.
As you plan your outdoor activities, keep in mind that certain people — young children and older adults, for instance — are at greater risk of heat-related illness. If your activities include people in this age range, pay close attention to them for any signs of distress

Rely on a backup plan

It's always a good idea to have a backup plan when the temperature soars. On days when the heat and humidity are high, avoiding the heat altogether and exercising inside may be your safest option. Indoor alternatives include exercising at the gym, swimming, mall walking or perhaps climbing stairs inside an air-conditioned building.

Keep it cool, play it safe

Your workouts help you live longer and stay healthier. But don't put your health at risk by working out in extreme heat. Follow the guidelines for working out in hot weather to avoid the risk of heat-related conditions.