Avoid exercising during the heat of the day when the sun is at its highest from 11 a.m. to 1 p.m.
Exercising in summer heat
By Pauline Oo
From eNews, July 22, 2004
Sweating is our body's way of cooling itself down. And in hot weather, especially with high humidity and when you're exercising, you can lose a great deal of body fluid from sweating and not drinking enough water. If you don't replenish what you lose, you could be asking for a heat-related illness. There are various degrees of this illness, with heat exhaustion being the most common and heat stroke being rare, but life threatening, explains U athletic trainer Moira Novak. Heat exhaustion typically occurs when body fluids are lost through heavy sweating and your sweat does not evaporate as it normally does to cool you. This can lead to decrease blood flow to the vital organs and shock. Heat stroke (also known as sunstroke), on the other hand, occurs when your body's temperature-control system, or sweat mechanism, stops working. Body temperature can rise rapidly, causing brain damage and death within minutes if the body is not properly cooled. According to Novak, the general symptoms of a heat-related illness include profuse sweating, paleness, muscle cramps, weakness and dizziness, nausea, and headache. Some people are more susceptible to it, such as the elderly, those with fair complexion, those with a history of heat-related illnesses or high blood pressure, and those who are overweight or in poor physical condition. Novak recommends the following to prevent heat-related illness:
- Avoid exercising during the heat of the day when the sun is at its highest from 11 a.m. to 1 p.m. Exercise in the early morning or in the evening after the sun goes down.
- Wear as little clothing as possible to help with sweat evaporation--forgo those long-sleeve T-shirts and pants. Also choose light-colored outfits, in white or yellow, because they can retain less heat.
- Hydrate your body. Drink 16 to 20 oz. of fluids an hour to 30 minutes before exercising; 5 to 8 oz. of water or fluids every 15 minutes during exercise; and drink continuously when you're done, even if you do not feel thirsty. "Water is adequate if you're just exercising for shorter periods of time, but if you're engaged in physical activity for longer than 45 minutes, drink some kind of metabolite-replacement drink like Powerade, which will help you replace glucose and sodium," advises Novak. Avoid alcohol and caffeine, which would only dehydrate the body further.
- If you have some history of heat-related illness, consult your physician about appropriate exercise or physical activity during the summer.
- "Be aware of some of the signs and symptoms of heat-related illness and use some good judgement when you're exercising in the heat," says Novak. "If you do see signs or experience any of the symptoms, stop exercising immediately, go to a cool environment, and try to rehydrate with non-alcoholic beverages."