久久亚洲国产成人影院-久久亚洲国产的中文-久久亚洲国产高清-久久亚洲国产精品-亚洲图片偷拍自拍-亚洲图色视频

您現(xiàn)在的位置: Language Tips> Easy English> Odd Question  
 





 
Why shouldn't you go swimming right after you eat?
[ 2006-08-09 11:15 ]
炎炎夏日,正是游泳的好時節(jié)。在清涼的水里暢泳,真是消暑的好辦法。不過,您千萬要記得剛吃完飯是不能游泳的,否則可能會抽筋、甚至有溺水的危險。這又是為什么呢?讓下面這篇小文章來告訴你吧!

"Don't go swimming for an hour after you eat" is actually a good piece of advice. If you get into the pool or the ocean right after you eat, you could risk drowning. Let's look at how this works.

The key is to know that your body will always work to take care of its energy needs and that conflicting needs cause problems. When you exercise, yoursympathetic nervous system, a part of the automatic nervous system stimulates the nerves to your heart and blood vessels. This nervous stimulation causes those blood vessels to contract or constrict. Thisvasoconstrictionincreases the resistance of the blood vessels in those tissues and reduces blood flow to those tissues. Working muscle also receives the command for vasoconstriction, but the metabolic byproducts produced within the muscle override this command and causevasodilation. So if most of your body is getting the message to cut the blood flow and your muscles are getting the message to boost the blood flow, the blood that would have gone to some of your organs will go instead to your muscles. Your body is taking from one part to give to another part, but it's OK if the organs that are getting less blood, such as your stomach or your kidneys, are not working.

But what if one of those organs does need the blood to do its work? If you have just eaten, then the food in your stomach begins to be digested. This requires greater blood supply to the stomach and intestines. Like metabolic byproducts in working muscle, the presence of food in the stomach overrides the commands by the nervous system to constrict the blood vessels in the stomach and intestines. Now you have a situation where the digestive system and working muscle both have increased demands for blood flow and are competing for the increased blood supply. What happens is that none of the systems gets enough blood flow to meet its needs and the tissues begin to cramp. This presents a serious problem if you are in the water and increases your risk of drowning. If you wait about an hour to allow some digestion to occur and food to leave your stomach, then your risk of cramps goes down.

sympathetic nervous system: 交感神經(jīng)系統(tǒng)

vasoconstriction: 血管收縮

vasodilation: 血管舒張

(英語點津 Annabel 編輯)

 
 
相關文章 Related Stories
 
 
 

本頻道最新推薦

     
  為什么下雪時天氣暖
  You are the smartest fish I've ever seen!
  Dog burger
  為什么老了脾氣好
  飛蛾為什么撲火

論壇熱貼

     
  開個題目大家扯:hotel & restaurant
  追求某人
  請教工商年檢如何翻譯
  How to translate “中國老字號”into English?
  "港股直通車"怎么翻譯?
  兩免一補怎么說?




主站蜘蛛池模板: 国产成人午夜精品5599 | 欧美色欧美色 | 免费男女乱淫真视频播放 | 黄色成人在线 | 亚洲gogo人体大胆西西安徽 | 欧美日韩亚洲国内综合网俺 | 国产精品久久久久久福利漫画 | 亚洲精品一区二区久久 | 欧美日韩顶级毛片www免费看 | 午夜丝袜美腿福利视频在线看 | 九一国产精品视频 | 欧美日韩中文字幕在线观看 | 亚洲伊人色综合网站小说 | 日本特黄特色 | 欧美一级毛片香蕉网 | 特黄的欧美毛片 | 久久香蕉国产观看猫咪3atv | 欧美影院久久 | 国产免费专区 | 成 人 免费 网站 | 免费看片亚洲 | 综合亚洲一区二区三区 | 亚洲欧美视频网站 | 99久久99视频 | 私人玩物福利 | 99福利网| 毛片在线播放a | 免费黄色欧美 | 亚洲成a v人片在线观看 | 国产精品久久久久久久久久免费 | 小泽玛利亚的一级毛片的 | 欧美另类老妇 | 中文字幕成人免费高清在线视频 | 国产精品久久久久网站 | 欧美特黄特色aaa大片免费看 | 久久久不卡国产精品一区二区 | 亚洲精品在线免费观看视频 | 91成人免费观看 | 91无套极品外围在线播放 | 亚洲精品久久久久久久777 | 国产一级爱做片免费观看 |