首页
登录
职称英语
[originaltext] A world-champion body builder has no more muscles than does a
[originaltext] A world-champion body builder has no more muscles than does a
游客
2023-09-16
36
管理
问题
A world-champion body builder has no more muscles than does a 90 pound weakling. So what makes him so strong? What other qualities does he need?
Muscles are made of thousands of stringy fibers—a number that is fixed during childhood—which contract when doing work. Strength does not depend on the number of fibers but on the function of their thickness and how many of them contract simultaneously.
Exercise actually damages the muscles. During the recovery stage, the muscle fibers increase in size. Exercise also trains more muscle fibers to work at one time. If a muscle is weak or untrained, for example, only about 10 percent of its fibers will contract, whereas up to 90 percent of the fibers in a weight lifter’s bulky biceps will contract.
Aside from strength, two other ingredients go into making an athlete: fitness and endurance. Fitness is related to the condition of the heart. During exercises, there is an increase in the amount of blood returning to the heart from the muscles. A typical volume for a runner at rest is about 5 quarts a minutes, compared with 30 quarts during a vigorous trial. This greater volume means more work for the heart—a muscular balloon that expands and contracts to take in blood and squeeze it out. Like any other muscle, the heart enlarges and gets stronger with routine exercise.
Endurance, or the length of time muscles can work, depends in part on how much fuel—in this case sugar—the muscles can store. A muscle that is continually exercised until it is exhausted of sugar tends to store more when it refuels at the next meal. And more sugar can translate into greater endurance the next time the muscle is put to the test.
选项
A、More muscles than average people.
B、A strong will.
C、Strength, fitness and endurance.
D、A strong heart.
答案
C
解析
What does an athlete need according to the passage?
转载请注明原文地址:https://tihaiku.com/zcyy/3019687.html
相关试题推荐
[originaltext]W:SweetHomeFurniture,canIhelpyou?M:Yes,[8]I’dliketob
[originaltext]W:SweetHomeFurniture,canIhelpyou?M:Yes,[8]I’dliketob
[originaltext]M:Anymessageforme,MissWhite?W:Justone,Mr.Brown.[6]You
[originaltext]W:WhenareyouleavingforCambridge,Dr.Berle?M:OnWednesda
Atwhattimeofdaydidthefirestart?Intheearly______.[br][originaltext]
Atwhattimeofdaydidthefirestart?Intheearly______.[br][originaltext]
Atwhattimeofdaydidthefirestart?Intheearly______.[br][originaltext]
Atwhattimeofdaydidthefirestart?Intheearly______.[originaltext]No
[originaltext]W:Hello,AirChinaWhatcanIdoforyou,Sir?M:CanIbookat
[originaltext]W:Hello,AirChinaWhatcanIdoforyou,Sir?M:CanIbookat
随机试题
Theterm"print"hasseveralmeanings,soitisimportanttounderstandexa
以钟山大学学生会的名义写一则关于金陵学院对钟山大学足球比赛的海报。时间:2005年3月12日下午2:30。地点:校体育馆可到三号办公楼体育俱乐部购票
皮影戏(shadowplay)是中国的一种民间艺术,拥有悠久的历史。皮影戏所需要的演员是用牛皮做的皮影人形,由一个或几个人控制着,并用光将它们反射到幕
Thehumanfaceisaremarkablepieceofwork.Theastonishingvarietyoffa
造成牙周炎的主要因素是A.龈下菌斑 B.龈下菌斑与龈下牙石 C.咬合创伤
下列关于华法林的叙述,不正确的是()A.起效慢 B.维持时间久 C.口
2007年1月1日,甲公司将一栋自用的房屋对外出租,董事会已决议作为投资性房地产
下列关于对小微企业金融服务收费问题,以下说法符合监管政策要求的是( )。A.银
赵女士在网上购买了一件衣服,快递员会在上午10:00~11:00之间送达,而赵女
某公司为建筑一栋商品房,向某市规划局、建设局和生态环境局等部门申请有关证照。请问
最新回复
(
0
)