Sports medicine experts have observed for years that athletes such as long distance runners, especially women athletes, often display a lack of iron. Now a new study by a team of Purdue University researchers suggests that even moderate exercise may lead to reduced iron in the blood of women.
"We found that women who were normally inactive and then started a program of moderate exercise of middle degree showed sings of iron loss," says Roseanne M. Lyle, associate professor at Purdue. Her study of 62 formerly inactive women who began exercising three times a week for six months was published in the journal Medicine & Science in Sports & Exercise.
Iron deficiency is very common among women in general, affecting one in four female teenagers and one in five women aged 18 to 45, respectively. But the ratio is even greater among active women, affecting up to 80 percent of female endurance athletes. This means, Lyle says, that "too many women ignore the amount of iron they take in". Women of child-bearing age are at greatest risk, since their monthly bleeding is a major source of iron loss. Plus, many health-conscious women increase their risk by rejecting red meat, which contains the most easily absorbed form of iron. And because women often restrict their diet in an effort to control weight, they may not consume enough iron-rich food, and are liable to experience a deficiency.
Exercise can result in iron loss through a variety of mechanisms. Some iron is lost in sweat, and, for unknown reasons, intense endurance exercise is sometimes associated with bleeding of the digestive system. Athletes in high-impact sports such as running may also lose iron through a phenomenon where small blood vessels in the feet leak blood.
There are three stages of iron deficiency. The first and most common is having low iron reserves, a condition that typically has no symptoms. Fatigue and poor performance may begin to appear in the second stage of deficiency, when not enough iron is present to form the molecules(分子) of blood protein that transport oxygen to the working muscles. In the third and final stage, people often feel weak, tired, and out of breath - and exercise performance is severely compromised.
"People think that if they're not at the third stage, nothing is wrong, but that's not true," says John L. Beard, who helped design the Purdue study. "You're not stage 3 until your iron reserves go to zero, and if you wait until that point, you're in trouble."
Beard and other experts say it’s advisable for people to have a yearly blood test. If iron levels are low, talk with a physician to see if the deficiency should be corrected by changing your diet and taking iron-rich foods or by taking iron-added pills.
“Select breads and cereals with the words ‘iron-added’ on the label,” writes sports diet expert Nancy Clark. “This added iron supplements the small amount that naturally occurs in grains.” Clark also recommends cooking in iron pans, as food can obtain iron from the pan during the cooking process.
64.Which of the following may be the title for the passage?
A.Science, sports and exercise
B.Correct iron deficiency
C.Women, Iron and exercise
D.Women, health and exercise
65.The third paragraph is developed mainly by________ .
A.organizing the details according to the order of time
B.presenting the result followed by specific causes
C.beginnign with details followed by a general statement
D.making comparisons ad contrasts
66.What does it mean when you are in the third stage of iron defieiency?
A.Nothing serious though you don’t have much iron stored in the body.
B.There is not enough iron to form the molecules of blood protein to transport oxygen.
C.The small blood vessels in your reet are beginnig to leak blood.
D.No iron is left in your body and you would be in trouble without urgent measures.
67.What is the writer’s attitude in writing this passage?
A.Defensive. B.Persuasive. C.Supportive. D.Objective.
科目:高中英语 来源:2012-2013学年山东省临沭一中高一10月学情调查英语卷(带解析) 题型:阅读理解
More and more people think it necessary to study in an English-speaking country and it didn’t take long at all for me to decide to come and study in UK.
Having been in the school for 2 months, I’m getting used to school life, and I am starting to make the most of my time in here. School starts at 9 o’clock every morning, and every Monday, Wednesday and Friday we have long days, in which we have 9 lessons and school finishes at 4 o’clock. Every Tuesday, Thursday and Saturdays we have short days, in which we have only 6 lessons and finish at 1 o’clock. After lessons, we have two hours of activity time, when you can choose from a wide range of activities, including all the major sports, such as rugby and football, and also the minor sports such as basketball and tennis.
As a boarder( 寄宿者),the quality of food is something I consider very important, and Merchiston has not let me down. The school kitchens are run by a professional food company, and the quality of food is very excellent and also they take the healthy diet very seriously: I remember once I was once asked to take more salad for my meal by a member of the kitchen staff(员工) for I didn’t have enough vegetables. This brings another point of being a boarder: you need to learn how to look after yourself and be responsible(负责) for yourself. One of the huge advantages of being a boarder is that we can have breakfast in the school, which means we don’t have to pull ourselves out of bed as early as the day pupils!
【小题1】The passage mainly tells us about _______.
A.the author’s school life in the UK as a boarder. |
B.the author’s opinion of the school life in the UK. |
C.the differences in school life between China and UK. |
D.the boarder life in a Britain middle school. |
A.has not enough time to study | B.likes to play tennis and basketball |
C.went to the school two months ago | D.finishes school at 4 o’clock |
A.15 | B.45 | C.27 | D.18 |
A.made me disappointed | B.made me pleased | C.encouraged me | D.amazed me |
A.is not used to the food there | B.has learned to have healthy diets |
C.is specially taken good care of | D.sleep as much as the day pupils |
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科目:高中英语 来源: 题型:阅读理解
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