No Sweat? No Good!

In the heat of summer, it's important to exercise with caution and pay attention to your body. Even if you're fairly well conditioned, overdoing it may lead to heat cramps, heat exhaustion or heatstroke, causing the body to lose its ability to sweat.

Age plays an important role in heat-related illnesses. Because older adults and people with chronic illnesses aren't able to sweat as easily as healthy younger adults, they are more susceptible to heat-related illnesses. Infants, young children, people who are obese, and people who have a mental illness are also more susceptible to heat-related illnesses. 

Heat-related illnesses can be classified into three categories: heat cramps, heat exhaustion, and the most severe, heat stroke. (A fourth category, heat injury, is similar to heat stroke without central nervous system dysfunction).

Heat cramps

Heat cramps are painful muscle spasms that occur after strenuous activity that produces a lot of sweat. Sweating causes a loss of water and salt from your body. It is the low salt level in the muscles that causes them to cramp.

To treat heat cramps, stop the activity, move to a cool or shady spot and drink plenty of liquids. Liquids could include juice, water, milk, or an electrolyte drink. Avoid caffeinated and alcoholic beverages. You may find that stretching, icing the area, or massaging sore muscles provides some relief. Avoid any strenuous activity for several hours. If the cramps haven't resolved in an hour, seek medical help.

Heat exhaustion

Heat exhaustion is a warning that the body is becoming overheated. It can lead to heatstroke if precautions aren't taken promptly. Heat exhaustion is caused by excessive depletion of water and salt from the body. The condition causes flu-like symptoms, including fatigue, weakness, nausea, vomiting, headache, dizziness, muscle cramps, and irritability or giddiness. People with heat exhaustion first appear flushed and then pale. Finally, the skin becomes cold to the touch and goose bumps appear; the victim then may start shivering.

These are danger signs that should be heeded quickly. Immediately stop the activity and move to a cool area. Drink plenty of cool but not iced liquids. Avoid caffeinated and alcoholic beverages. Apply a cloth soaked in lukewarm water to the neck, armpits and groin area, or immerse the person in cool or cold water. Consult with your doctor.

Heatstroke

If heatstroke occurs, it means the body is unable to regulate its internal temperature. Heatstroke is defined as core body temperature above 104 degrees Fahrenheit (40 degrees Celsius) and central nervous system dysfunction. Heatstroke is the most serious of heat conditions and can be life-threatening, so prompt medical treatment is critical. In heatstroke, body temperature rises and sweating stops, making it impossible for the body to cool itself. Loss of consciousness is often the first sign of heatstroke. The skin becomes hot and dry, followed by rapid pulse and possible throbbing headache, delirium, or fainting. Other symptoms include seizures and hallucinations.

Heatstroke is a medical emergency. Call an ambulance immediately if someone displays these symptoms. Then, take action while you are waiting. Get the person to a cool area. Cool him or her in any way you can by spraying with cool water from a hose or placing the person in a tub of cool water. If the humidity is low, wrap the person in a cool sheet and fan him or her.

Heatstroke affects mostly older adults, particularly if they have a chronic illness. It also is seen in military recruits in training, long-distance runners, and people who have skin conditions that interfere with the body's ability to sweat.

How to avoid overheating

To help prevent heat-related illnesses, follow these guidelines:

  • If you exercise between noon and 4 p.m., when the sun's rays are most intense, take extra precautions to remain hydrated. If you notice the heat is getting to you, take a break.

  • Wear loose, light-colored clothing and a large-brimmed hat.

  • Stay in the shade as much as possible and avoid reflective surfaces such as concrete.

  • Increase your water intake; avoid alcohol and caffeine.

  • Don't wait until you feel thirsty to drink water; thirst is a late warning sign that you are low on fluids. Drink 4 ounces every 30 minutes.

  • Build up your exercise routine gradually over a few weeks, to give your body time to acclimate.

  • Know that higher humidity increases the risk of heat-related illness, and plan accordingly. 

  • Never leave anyone in a closed, parked vehicle in the sun.