Is It Safe to Swim in Excessive Heat Warnings?

The National Weather Service issues excessive heat warnings when the temperature and humidity reach dangerous levels that can cause physical illness. The National Oceanic and Atmospheric Administration's criterion for issuing an excessive heat warning is the heat index, the combination of air temperature and humidity. When the heat index exceeds 105 degrees for 3 hours a day, 2 days in a row, or anytime the index exceeds 115 degrees, the NWS issues an excessive heat warning. Swimming in hot weather is one of the best ways to cool off and avoid heat exhaustion or stroke, as long as the water is not hot.

Function

• By its nature, water provides one of the easiest ways to cool off. Human beings sweat to cool themselves. Water takes tremendous energy away from the surface of the skin when it evaporates, which cools the body. The water molecules continually absorb or release heat. Using the energy cycle to lose body heat when swimming when the air temperatures are excessively hot can lower body temperatures quickly.

Benefits

• Swimming or immersing the body in water in hot weather is a comfortable option for exercise. Water displaces body weight and creates resistance, providing an impact-free way to burn calories on a hot day. Exercise raises the heart rate, which helps to circulate blood. The brain releases endorphins during exercise that make people feel better both physically and mentally. During a long stretch of hot weather, swimming can help people stay in shape and feel better. Being in the water also stretches the muscles, which can reduce aches and pains.

Considerations

• When the weather warms, so does the pool water. The sanitizing pool chemicals also evaporate faster in warmer swimming pools, and as more people use the pool, chemicals deplete faster. Making sure the swimming pool stays chemically balanced is the job of pool maintenance specialists. Swimming pools that provide showers and require bathers to use them before entering the pool may be cleaner than those that do not. Some states, jurisdictions or pool managers also require that untrained toddlers and children wear special swimming diapers that hug the legs and waist tightly to prevent leakage.

Warnings

• Wearing waterproof sunscreen during the summer, especially when swimming, reduces the harmful effects of the sun, even on cloudy days. Parents or caretakers should never rely on flotation devices as safety products for infants, toddlers and children who cannot swim. Young children have a higher sensitivity to heat and cold. When a child's lips start to turn blue, it's time to take her out of the pool and wrap her with a towel until she warms up.