It is summer and people are heading outside to exercise and train. With high temperatures hitting the 90s, athletes of all kinds may find it difficult to cool down and that can lead to danger.

Heat illness, or the even more severe heat stroke, occurs when the core body temperature reaches 104°F or higher. It can cause permanent damage, or death, if not corrected within 30 minutes of elevated temperatures. The elderly (those over 75) are at the highest risk for heat illness. That doesn't mean those who are younger are off the hook. People exercising and athletes in training – especially football players in pads and helmets – can suffer the effects of high heat. Heat stroke death from exercise is one of the three leading causes of sudden death in athletes. There are simple things that can be done to prevent problems from the heat. You should understand the heat index, know the best time of day to exercise, understand the importance of staying hydrated and know how to acclimatize (adjust) to the environment.

The heat index is a useful guide in determining when it's best to exercise. The Occupational Safety and Health Agency (OSHA) recommends caution when the heat index is below 91°F. More caution is recommended, including heat safety activity and pre-planning, for a heat index of 91° to 103°F. This includes frequent water and shade breaks. OSHA recommends no exercise with a heat index over 103°F.

Precautions you can take to prevent heat illness include exercising in the early morning, when the heat index is lower and there isn't so much direct sun. The body adapts to the heat overtime, so it is important to adjust to the heat over a period of two weeks. Thirst is not a good indicator of hydration levels. People do not become thirsty until after they have lost three to five percent of their body water. So keep hydrated and drink fluids to keep urine color a light yellow. This is usually 16 ounces of water per half hour of exercise.

When the body begins to lose its ability to prevent overheating, its core temperature rises, resulting in certain signs and symptoms. Heat illness can be considered as a spectrum, ranging from mild (heat cramps) to severe (heat stroke). Heat stroke if left untreated can result in death. Athletes who are dehydrated can experience minor symptoms as well. These include: swelling of the hands and feet, muscle cramps and lightheadedness. Major symptoms of dehydration include: mental status changes (confusion, agitation, irritability, lack of coordination), sweating stops but skin is hot, headaches, nausea and goose bumps (skin acting like it is cold in the heat).

Any athlete suspected of having severe heat illness requires immediate cooling. Treatment should not be delayed by transport to the hospital. Whole body immersion in cold (ice) water is key to treating severe heat illness. The next best option is ice towels and cold showers. Call 911 when cooling has started. Some people think about giving fever-reducing medications, but elevated temperature from fever is a much different mechanism for increased body temperature and should not be given for heat illness. Minor heat illness symptoms are treated by stopping exercise, moving to the shade, giving fluids, stretching cramped muscles and elevating swollen limbs.

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