The late Margaret Thatcher earned a reputation for getting by on four hours a night.Tirelessness became part of the former British PM's mystique and her officials had to keep up with her. They could find themselves working on a speech until the small hours of the morning.
 

Winston Churchill used to sleep four hours a night during the war

Another British head of government, Winston Churchill, survived on four hours a night during the Second World War. But as the BBC reporter Tom de Castella points out, what is less often noted is that he had regular afternoon naps in hispyjamas.

Napoleon Bonaparte was not a man to sleep on the job. When asked how many hours of sleep he needed, the famous French general is said to have replied: "Six for a man, seven for a woman, eight for a fool."

How about ordinary people? Should we try to stifle our yawns and embrace insomnia?

If you want to impress colleagues in the world of business it's certainly something to strive for. High-profile chief executives from Marissa Mayer at Yahoo! to Pepsi's Indra Nooyi get by on four hours a night, while Donald Trump claims to survive on three.

Geraint Anderson, author of City Boy, who worked as an analyst and stockbroker for 12 years, says: "There was a real macho competition in the City about sleep. One of the ways of getting respect was bragging about how little you got".

Experts say that there's nothing wrong with the habit of burning the midnight oil. The only rule is to sleep long enough to feel refreshedwhen you wake up.

Prof James Horne, at Loughborough's sleep research centre, says thatmood is critical. Soldiers high on adrenalin can function on little sleep: "If you're despondent, you tend to sleep more; if you're excited you need less".

Some artists think that sleep deprivation can make them more creative but it might be worth carrying a pillow around. Keith Richards, the Rolling Stones guitarist, once stayed awake for nine days. When fatigue got the better of him, he collapsed and broke his nose.

Glossary 词汇表

the land of Nod梦乡

tirelessness不知疲倦的

mystique神秘感

to keep up with跟上，赶上

the small hours of the morning凌晨

a nap小睡，打盹

pyjamas睡衣

to sleep on the job上班时间睡觉

to stifle a yawn忍住哈欠

insomnia失眠

to strive for争取，力求

to brag about吹嘘，炫耀

to burn the midnight oil熬夜，开夜车

to feel refreshed感到精神焕发、神清气爽

mood情绪

high on adrenalin大量分泌肾上腺素

to function(可正常)工作

despondent沮丧的，意志消沉的

sleep deprivation睡眠不足

fatigue疲劳