If you want to be successful, you might have to roll out of bed a little earlier.

Waking up early was a common trait among CEOs surveyed by Jim Citrin at Yahoo Finance. It's also frequently cited by CEOs who relay their morning routines to Inc in one of its features, "The Way I Work."

Many of tech's go-getters function well on little sleep. Others are woken up by product releases, emails, and the desire to workout and meditate before starting their day.

Here are 12 successful people who often wake up before the crack of dawn.

Yahoo CEO Marissa Mayer only gets about four hours of sleep.

Marissa Mayer isn't much for sleep. The Yahoo CEO presumably wakes up early since she says she only gets between four and six hours of sleep on any given night.

Apple CEO Tim Cook can be found in the gym by 5 a.m.

Tim Cook, Apple's CEO, starts sending emails around 4:30 a.m., according to Gawker's Ryan Tate. After that he works out. He's boasted about being the first in the office and the last out.

Steve Jobs was also an early riser, starting his days around 6:00.Maybe Tim Cook fashioned his early morning routine after his former boss, Steve Jobs.

Jobs told Time back in 1999 about how he started his days: "I'll wake up sixish and work a little before the kids get up. Then we'll have a little food, finish up some homework, and see them off to school. If I'm lucky I'll work at home for another hour, but oftentimes I'll have to come in. I usually get [to Apple] about nine. Eight or nine. Having worked about an hour and a half or two hours at home."

Square CEO Jack Dorsey wakes up before dawn for a 6-mile run.

Dorsey described his morning routine to New York Magazine, revealing that he wakes up at 5:30 a.m. to meditate and go for a 6-mile jog.

He kept up that routine during a period when he shuttled back and forth between Square and Twitter, spending around eight hours a day at both companies.  Andreessen Horowitz partner Jeff Jordan used to get to the office at 5 a.m.

Jeff Jordan, formerly of PayPal and OpenTable, now works for Andreessen Horowitz and leads deals in companies like Fab and Pinterest.

Prior to joining a16z, Jordan told The New York Times that he got into the office by 5 a.m. and didn't leave until after 7 p.m.

Few people rise earlier than Padmasree Warrior, Cisco's former chief technical and strategy officer.

One of the most well-known women in business today, Cisco's former CTO Padmasree Warrior's morning routine consists of waking up at 4:30 a.m., reading her email for an hour, checking out the news, exercising, and prepping her son for school — all before 8:30 a.m., according to Yahoo Finance.

Warrior was also previously the CTO of Motorola.

AOL CEO Tim Armstrong starts his day at 5:00 a.m. and peruses AOL.

Tim Armstrong wakes up so early, he has to hold himself back from sending emails and interrupting the morning habits of others (i.e. sleeping).

The AOL CEO tells The Guardian he wakes up at 5:00 or 5:15 a.m. and starts sending emails around 7:00 a.m. During those two hours, Armstrong exercises and reads. He also chats with his middle daughter, who is an early riser.

"I am not a big sleeper and never have been. Life is too exciting to sleep," Armstrong tells The Guardian.

Xerox CEO Ursula Burns wakes up by 5:15 a.m.

Burns uses early-morning hours to get caught up on emails, getting up at 5:15 and sometimes working until midnight, according to Yahoo Finance.

She also uses the time to fit in a workout, according to Laura Vanderkam's "What The Most Successful People Do Before Breakfast." Burns schedules an hour of personal training at 6 a.m. twice a week. 

Ericsson CEO Hans Vestberg's nights and days are often jumbled together into one long work session.

Hans Vestberg, CEO of Ericsson, rarely arrives at the office past 8:00 a.m. When asked how early he wakes up, he simply says, "early."

Before he goes to work, Vestberg works out and sends emails. His company's nights and days morph into each other; it's always working. Vesberg goes to bed "quite late" but says he gets enough sleep.

"Our company never sleeps: We have business in 180 countries, so there are no real mornings or nights," he tells The Guardian.

Vodafone CEO Vittorio Colao rises by 6 a.m.

Vittorio Colao wakes up at 6:00 a.m, according to The Guardian. He exercises then works to about 10:45 p.m., with a small gap for dinner with his family. He heads to bed by 11:30 p.m.

Paul English of Blade gets up by 6 a.m. and meditates.

Paul English, cofounder of Kayak and travel startup Blade, tells Inc he wakes up by 6 a.m.

"I usually meditate for a few minutes to quiet my mind before I get out of bed," he says. "I get up around 6 every morning. After I check email on my BlackBerry, I go exercise. I've been practicing yoga for about 10 years. I built a meditative room in my house."

Zulily's Darrell Cavens wakes up at 6 a.m. for his company's daily sale

Zulily, an online-only retail company for kids, kicks off every morning with a 6 a.m. (Pacific) sale.

That's when its creator, Darrell Cavens, gets a notification on his phone, which serves as his alarm.

"Part of my night routine is to look at a preview of what the site’s going to look like the next day — so the very first thing I do is pull up the site on my phone to make sure they match," he tells Inc.

This story first appeared on Business Insider