Do you need a lot of sleep? Some famous leaders are thought to have spent little time in the land of Nod so keen they were on their high-powered jobs.
The late Margaret
Thatcher1 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.
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
noted2 is that he had regular afternoon naps in his
pyjamas3.
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
stifle4 our yawns and embrace
insomnia5?
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
Trump6 claims to survive on three.
Geraint Anderson, author of City Boy, who worked as an
analyst7 and
stockbroker8 for 12 years, says: "There was a real macho competition in the City about sleep. One of the ways of getting respect was
bragging9 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 refreshed when you wake up.
Prof James Horne, at Loughborough's sleep research centre, says that mood is critical. Soldiers high on adrenalin can function on little sleep: "If you're
despondent10, you tend to sleep more; if you're excited you need less".
Some artists think that sleep
deprivation11 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
fatigue12 got the better of him, he
collapsed13 and broke his nose.