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UC Davis Medical Center

UC Davis Medical Center

Beat the heat when exercising outdoors

Take action at the first signs of heat illness to avoid emergencies

women running
Heat illness can rapidly lead to a medical emergency, so it is essential to take action at the first warning and it's crucial to know the signs.

Exercise can become downright hazardous when temperatures soar. But by taking adequate precautions and knowing the danger signs of dehydration and heat stroke, everyone can still have fun in the sun this weekend and throughout the hot summer.

"Exercise and activity are crucial to help you stay healthy, but it's important to be careful in the summer to avoid heat stroke, deydration and other consequences of overexertion," said Jeff Tanji, a physician at UC Davis Health System who specializes in sports medicine. "Luckily, a little common sense goes a long way."

Tanji offers the following tips to beat the heat:

Time it right

If possible, schedule exercise during the cooler morning and evening hours. And keep in mind that out-of-town visitors may not be accustomed to our temperatures and should especially take it easy the first few days. Even pro athletes adjust their routines during the first five days in a new climate.

Don't forget regular time-outs

This is especially important for youngsters who aren’t always aware that they need rest periods and water breaks. Schedule a minimum of 10 minutes for every hour of exercise. Children, older people and those who are less fit need more rest. Of course, everyone should spend more time chilling out when it's particularly hot.

Stay hydrated!!

Before starting out on any outdoor activity, have a big glass of your favorite cool drink.

Make sure kids drink plenty of water since they don’t realize how important it is to stay hydrated.

Heat illness can rapidly lead to a medical emergency, so it is essential to take action at the first warning.

Competitive athletes should tank up with two big glassfuls of fluids at least two hours before an event. Plain water is best, but fruit juices and Gatorade-type sports drinks are fine, too. Just avoid alcohol and caffeine, which contribute to dehydration.

Whenever possible, drink during exercise as well, at a rate of about 5 to 10 ounces every 15 minutes. For people engaging in prolonged exercise over a period of hours, it's important to replace salts and add energy with sports drinks rather than plain water.

Dress for the occasion

Football players with bulky, tight-fitting uniforms will be at higher risk for heat problems than runners in shorts and tanktops. Coaches and athletes need to adjust fluid requirements and resting times with these factors in mind on hot days.

Spectators also can get hot and tired sitting in the bleachers on a hot day. Wearing a wide-brimmed hat and light-colored, loose clothing made of cottons and other light, breathable fabric is recommended, and applying sunscreen to all exposed areas every few hours will help prevent sun damage to skin.

Act before emergency

Heat-induced illnesses include muscle cramps, heat exhaustion and heat stroke.

Heat illness can rapidly lead to a medical emergency, so it is essential to take action at the first warning. It's crucial to know the signs of "heat illnesses."

Heat-induced illnesses include muscle cramps, heat exhaustion and heat stroke. These conditions often occur in people working hard or exercising in hot weather, but can arise in anyone on a hot day. People especially at risk are the elderly, children, overweight individuals and those with heart conditions or taking certain medications, such as diuretics (water pills).

Muscle cramps are one painful form of heat illness. These frequently occur in the legs or abdomen and are due to salt depletion from excessive sweating. The cramps are usually relieved by rest, stretching and rehydration. Tanking up on fruit juice with a pinch of salt added or drinking sports drinks can help prevent salt depletion during hot weather.

Heat exhaustion is an early stage of heat stroke. The person feels excessively tired, weak, and nauseous, and may feel dizzy and even pass out briefly. The skin is cool and clammy, and may appear either flushed or pale. Have the person sit or lie down in a shady location and give cool drinks. Try anything to cool the victim down: Loosen or take off extra clothes, sponge with cold water, and place him or her near a fan. If the person does not feel better after a short while or if symptoms worsen, seek medical care.

Heat stroke can be a very dangerous condition. The body stops sweating and the internal temperature climbs to high levels. The skin will be quite dry and hot. The victim may become confused, agitated and have blurry or double vision. These symptoms indicate an extremely dangerous state. Have the person lie down, and seek medical help at once while others continue efforts to cool the victim down.