A cross-country mountain marathon in northwest China's Gansu Province on May 22nd has turned into a public safety accident. According to the local government, 21 runner died from hypothermia(体温过低症) after being hit by extreme weather.
Hypothermia is one of the biggest challenges of outdoor activities. It means cooling, or even freezing of the body.
The cooling could be fast enough to kill a person. Outside air temperature doesn't have to be very low. In fact, hypothermia can happen when the temperature is 50℉(华氏), and it often does.
For the body to run well, its temperature must stay about 98.6℉. People produce(生产) more heat than they need. In hypothermia, however, the body loses more heat than it produces. This condition often happens when a person gets wet.
One of the most terrible accidents that can happen to a fisherman is to fall into the sea and become wet.
Wind also makes heat loss faster. The wind cools the water. At 50℉, water is terribly cold. If a person's clothes are wet, heat moves rapidly from the body to the water.
Whenever you're outside, keep dry. Wear rain clothes. While you're moving—hiking or skiing, for example—your body makes a lot more heat than it does when you're resting. However, you may find that once you stop hiking, your production(产量) of body heat may drop suddenly by as much as 50 percent. You may start toshiverand become unable to control the shivering. You may turn into hypothermia: your speech will slow, you won't remember well, and you will find you cannot hold things. You may become too tired, but you must not sleep—or you might die.
