There are only 24 hours in a day; that’s something even business titans and world leaders can’t change.
But you can change how you use them. Some of the most successful people in the world not only work extremely hard in the hours they have, they create more of them by forgoing sleep.
Some people are genetically wired to wake up earlier or sleep less. Others seem to thrive on less sleep only through sheer determination. For executives like PepsiCo’s Indra Nooyi and Twitter’s Jack Dorsey, sleep is often sacrificed in order to excel at work and still manage to have a personal life.
To be sure, sleep deprivation — defined as getting very little sleep in one night or consistently getting less than seven to eight hours over time — comes with consequences. Fatigue can hurt performance just as much as or even more than alcohol impairment when taken to extremes. So while waking up earlier can be beneficial, be cautious about following these examples and burning the candle at both ends.
Carolyn Cutrone contributed to an earlier version of this piece.
Being at the head of two exciting tech startups doesn't leave too much time for rest. In 2011, Dorsey told Kara Swisher that he was spending eight to 10 hours a day at Square, and eight to 10 hours a day at Twitter.
That left him somewhere around four to six hours a night to sleep, possibly less when travel time is factored in. He still manages to get up at 5:30 every morning to take a jog.
After his turnaround of Fiat and part in the resurrection of Chrysler, Marchionne is one of the most renowned executives in the automotive world.
He's kept a punishing schedule throughout. According to Alex Taylor at Fortune, Marchionne works on four hours of sleep a night, fuelled by coffee and cigarettes.
Morrissey told The Guardian that she gets up 'at 5 in the morning, sometimes earlier,' and immediately starts sending emails until her kids get up. She has family dinner scheduled at 7:30 p.m. but works again after that, sometimes for as much as two hours, prepping for the next morning's meetings.
She gets five to six hours a sleep each night and admits to feeling a bit sleep-deprived. But that's the job, especially when you've got nine children in addition to running a global investment company.
After dropping out of NYU to pursue a career in fashion design, Ford quickly landed a position as design director at Gucci. Under his leadership, Gucci's value increased by 90%.
He does not attribute this success to talent, but says its due to his energy. It must be pretty intense, considering that Ford sleeps only three hours a night.
Inc. reports that during his time at the helm of Southwest, Kelleher slept only four hours a night.
That hard work paid off. Although Kelleher is now retired, Southwest remains one of the few continuously-profitable airlines.
Smolyansky took over the dairy company her father had started in 2002 at the young age of 27.
It took a great deal of work for her to do so. She told Fortune that she managed it by sleeping as little as four hours many nights.
Stewart keeps an impressive schedule while running her business, and according to CNN Money, she sleeps less than four hours a night.
You would think that the former General of all U.S. and NATO forces in Afghanistan would have needed an immense amount of energy to perform his job.
Most people get theirs from a few meals a day and a good night's sleep. Not McChrystal. According to Time, he eats just one meal per day and sleeps only four hours a night.
Michael Lewis' profile in Vanity Fair revealed the President's usual schedule: He goes to bed at about 1:00 a.m and is up at 7:00 a.m., meaning he sleeps just six hours a night.
Obama sometimes gets less sleep than that. Aides in the White House must constantly decide what type of crisis is important enough to wake the President during his few hours of shut eye.
In addition to hosting 'The Tonight Show,' Leno still manages to tour on the comedy circuit, averaging over 150 gigs a year.
Perhaps mimicking some of the people that stay up to watch his 11:35 p.m. show, Leno only sleeps about five hours a night.
Though he's changed his sleep habits after his heart surgery, Clinton was renowned for sleeping only five or six hours a night throughout his presidency.
It's apparently a habit he developed quite early. According to The New York Times, a professor at Georgetown told him great men require less sleep.
Last year, Ma Ying-jeou was elected to his second term as Taiwan's President.
The New York Times ascribes his success to an intense discipline and work ethic: He sleeps five hours a night and routinely rises at dawn to jog.
According to The Daily News, Trump credits his success to sleeping only three to four hours each night to stay a step ahead of his competition.
He does not seem to understand how sleep and success can co-exist according to his quote in The Daily News: 'How does somebody that's sleeping 12 and 14 hours a day compete with someone that's sleeping three or four?'
Thomas Edison: The famous inventor only required about three to four hours of shut eye each night, according to The New York Times. He regarded sleep as 'a heritage from our cave days.'
Benjamin Franklin: In his autobiography, Franklin published his typical daily schedule. He appears to have slept only five hours a night, from 11:00 p.m. to 4 a.m.
Nikola Tesla: An even more restless inventor than Franklin or Edison, a biography of Tesla by a personal friend claims that he would sleep as little as two hours a night.
Margaret Thatcher: Britain's longest serving Prime Minister was famous for getting by on just four hours of sleep each night while in office, according to the BBC.
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