【英语时差8，16】水上运动

 In 1993, water aerobics¹ was only for senior citizens or patients in rehab. Nowadays, it encompasses² a variety of trendy underwater sports, all of which are healthy.

"The body has 90 percent support when under water. That means the joints⁴ only have to offer 10 percent support," says Theodor Stemper, a sports scientist at the Bergischen University in Wuppertal, Germany.

The buoyancy adds comfort and alleviates⁵ the pressure on the joints. "That lets a person participate ... even if they're overweight or have never done it before," says Stemper. Aqua fitness is also great for pregnant women or people suffering from a joint³ injury.

Apart from buoyancy, the water pressure can prove beneficial. For every extra meter of water depth, the pressure rises by 0.1 bar.

"That ... promotes the circulation of blood," says Stemper. "It also promotes the metabolism⁶."All these effects can be achieved in aqua relaxing and aqua balancing, which involve minimal⁷ physical exertion⁸.

Other forms of aqua fitness require some form of activity. And all have positive effects on health.

"Aqua-jogging, aqua-running ［and］ aqua-aerobics all help train heart and circulatory endurance," adds Peter Freyer, a sports instructor⁹ in Duisburg, Germany.

Training in water always has a bigger impact than training in the air, as water is 1,000 times denser¹⁰.

"That means I'm working against significantly greater resistance," says Freyer. "A lot more is being demanded of the body."

1 aerobics   

n.健身操，健美操，韵律操

参考例句：

• Doing aerobics is a good way to improve one's health.做有氧健身操是改善健康状况的一个好方法。
• Aren't you going to the aerobics class this morning?今天上午你不是去上有氧运动课吗？

2 encompasses   

v.围绕( encompass的第三人称单数 )；包围；包含；包括

参考例句：

• The job encompasses a wide range of responsibilities. 这项工作涉及的职责范围很广。
• Its conservation law encompasses both its magnitude and its direction. 它的守恒定律包括大小和方向两方面。 来自辞典例句

3 joint   

adj.联合的，共同的；n.关节，接合处；v.连接，贴合

参考例句：

• I had a bad fall,which put my shoulder out of joint.我重重地摔了一跤，肩膀脫臼了。
• We wrote a letter in joint names.我们联名写了封信。

4 joints   

接头( joint的名词复数 )； 关节； 公共场所（尤指价格低廉的饮食和娱乐场所） （非正式）； 一块烤肉 （英式英语）

参考例句：

• Expansion joints of various kinds are fitted on gas mains. 各种各样的伸缩接头被安装在煤气的总管道上了。
• Expansion joints of various kinds are fitted on steam pipes. 各种各样的伸缩接头被安装在蒸气管道上了。

5 alleviates   

减轻，缓解，缓和( alleviate的名词复数 )

参考例句：

• Heat often alleviates pain. 热常常能减缓疼痛。
• A cold compress often alleviates pain. 冷敷常会减轻疼痛。

6 metabolism   

n.新陈代谢

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• All living matter undergoes a process of metabolism.生物都有新陈代谢。

7 minimal   

adj.尽可能少的，最小的

参考例句：

• They referred to this kind of art as minimal art.他们把这种艺术叫微型艺术。
• I stayed with friends, so my expenses were minimal.我住在朋友家，所以我的花费很小。

8 exertion   

n.尽力，努力

参考例句：

• We were sweating profusely from the exertion of moving the furniture.我们搬动家具大费气力，累得大汗淋漓。
• She was hot and breathless from the exertion of cycling uphill.由于用力骑车爬坡，她浑身发热。

9 instructor   

n.指导者，教员，教练

参考例句：

• The college jumped him from instructor to full professor.大学突然把他从讲师提升为正教授。
• The skiing instructor was a tall,sunburnt man.滑雪教练是一个高高个子晒得黑黑的男子。

10 denser   

adj. 不易看透的, 密集的, 浓厚的, 愚钝的

参考例句：

• The denser population necessitates closer consolidation both for internal and external action. 住得日益稠密的居民，对内和对外都不得不更紧密地团结起来。 来自英汉非文学 - 家庭、私有制和国家的起源
• As Tito entered the neighbourhood of San Martino, he found the throng rather denser. 蒂托走近圣马丁教堂附近一带时，发现人群相当密集。