英文原文

Sales of laptop computers passed desktops in the U.S. for the first time ever this fall, according to market-research firm IDC.

That's bad news for backs, necks and shoulders.

'Laptops are inherently unergonomic -- unless you're 2 feet tall,' says physician Norman J. Marcus, a muscle-pain specialist in New York City.

When you work at a computer, the keyboard should be at elbow height, so your upper and lower arms form an angle of 90 degrees or more and your forearms are supported by armrests. The monitor should be roughly at eye level so you can lean back in a chair with back support.

But most users simply set their laptops on a desk or table. The keyboard is too high, which makes your arms reach up, your shoulders hunch and your wrists bend down. The monitor is too low, which pulls your head and neck forward and down and puts a strain on your back.

That's OK if you use your laptop occasionally, for short periods. But if you use one for hours at a stretch -- as do millions of college students, business travelers, telecommuters, video-gamers and growing numbers of office workers -- you're setting yourself up for muscle problems that can make your entire upper body hurt.

Ergonomics experts have warned about laptop problems for years -- mostly in vain. People continue to abandon bulky desktops in favor of the ever-sleeker, lighter portables. And WiFi connections let us use laptops anywhere -- in bed, on the floor -- in all kinds of contorted positions.

中文译文

据市场研究公司国际数据公司(IDC)的数据，今年秋季美国笔记本电脑销量有史以来首次超过台式电脑销量。

但对人的颈、肩、背来说，这是个坏消息。

纽约市肌肉疼痛科医生诺尔曼·马库斯(Norman J. Marcus)说，笔记本电脑本质上是不符合人体工程学的，除非你身高只有两英尺。

当你在电脑前工作时，键盘应该和肘部齐高，这样你的大臂与小臂成90度角或更大的角度，小臂可以放在椅子扶手上。显示器应该大概和眼睛处于同一水平线，这样你就能往后靠在椅背上。

但是，大部分使用者都只是把笔记本电脑放在书桌或是普通桌子上。键盘放得太高，你必须把胳膊伸得老高，耸起肩膀弯着手腕。显示器太低，你的脑袋和脖子都必须往前下方伸，使你的背部紧张。

如果你只是偶尔、短时间地用一下笔记本电脑，这样做不会有太大问题。但是，如果你一坐就是几个钟头（就像好几百万大学生、商务旅客、网络上班族、游戏玩家，以及越来越多的办公室白领一样），那你就是在和自己的肌肉过不去，这可能会让你的整个上身疼痛。

人体工学专家多年来一直在提醒笔记本电脑的问题，但是往往是徒劳无功。人们继续丢掉笨重的台式电脑，转向更加轻薄的笔记本电脑。而且无线上网技术还让我们可以在任何地方使用笔记本电脑──床上、地板上──姿势也可以千奇百怪。