CEOs of companies like Apple get up early — and don't sleep much

• CEOs of major companies can have pretty extreme sleep schedules.
• They're often getting up early in the morning and going to bed late to manage their busy work days.

Being a CEO of a major company is a tough job. Work days can be long and grueling, and often, there's not enough time for a full night of rest.

Take Vlad Tenev, CEO of financial platform Robinhood. He averages just over four hours of sleep a night, he told Axios. He's usually actually sleeping fewer hours than that on the weekdays, and making up for it on the weekends.

While Tenev didn't say exactly what time he's going to bed and waking up in order to manage his busy work days, it's not uncommon for other leaders to be rising pretty early in order to pack in everything they need to do.

Apple CEO Tim Cook usually wakes up between 4 and 5 a.m. and spends the first hour of his day reading through emails. He calls himself an "early bird" and believes he has more control over his time in the morning than in the later hours of the day.

American Express CEO Steve Squeri rises at around 5:45 a.m., and is usually out the door in about 15 minutes. His 17-hour work days are jam-packed with meetings, and he winds down for about an hour at night before calling it a day around 11:30 p.m.

That's not to say there aren't CEOs going for the 8-hour gold standard.

Meta CEO Mark Zuckerberg has previously said he aims for eight hours of sleep a night and uses an Oura ring to track his sleep.

Others, like the multimillionaire biotech CEO Bryan Johnson, are focusing on sleeping well as part of an intensive age-reversing regimen. Johnson is usually in bed by 8:30 p.m. and up before 6 a.m. He even eats his last minute of the day by 11 a.m. so that when he goes to bed his resting heart rate is between 46 to 50 beats per minute.

And Sam Altman at OpenAI said in 2018 that "sleep seems to be the most important physical factor in productivity for me." Still, the CEO is "a bad sleeper in general, and a particularly bad sleeper when I travel."