Before brokering multimillion-dollar real estate deals, Ryan Serhant, star of Bravo's "Million Dollar Listing New York," is breaking a sweat.
In a new video posted to YouTube, Serhant gives fans a glimpse into his daily routine, which starts with him heading to the gym at 4:50 a.m. for some intense exercise.
Serhant, who works out at Dogpound — a New York City gym that boasts clients like high-profile business people, actors and Victoria's Secret models — says he used to work out at night. But as he got older and his job got harder, it was the last thing he wanted to do after a long day.
"I'd be exhausted, I'd be tired, I'd be thinking about my day, I'd be thinking about tomorrow," Serhant says.
"And I always used to think people who woke up super early were…crazy," he continues. "Now I can't imagine doing it any other way. Because now, by 6:30, 7 o'clock, every morning, the hardest part of my day, physically and mentally, is now over."
Indeed, by 7:55 a.m., Serhant, who has his own upcoming Bravo spin-off "Sell It Like Serhant," is in the car being chauffeured to the first of back-to-back appointments. While bouncing between meetings and listings, the video shows him eating what looks like a healthy lunch in the car. He says he has two client dinners that night and then will head home and pass out by 11:30 or midnight.
Serhant's penchant for early morning fitness is shared by some of the most successful billionaires.
Virgin Group founder Richard Branson routinely wakes up at 5 a.m. to work out. "Getting up and at it early gives me time to get on top of things, and chart my day effectively," says Branson in a blog post.
And Facebook CEO Mark Zuckerberg is a believer. "Staying in shape is very important. Doing anything well requires energy, and you just have a lot more energy when you're fit," Zuckerberg says. "I make sure I work out at least three times a week — usually first thing when I wake up."
Twitter and Square CEO Jack Dorsey, who reportedly tackles 18-hour work days, also wakes up at 5 a.m., mediates for 30 minutes, and then works out, according to an "ask me anything" on tech website Product Hunt.
"Same thing every day," Dorsey says. "[It] allows a steady state that enables me to be more effective."
And science seems to bear out this thinking. In a 2013 article in Scientific American, neuroscientist Justin Rhodes explains that there is evidence "we think and learn better" when we exercise. According to Rhodes, the boost may be due to increased blood flow to the brain, and the fact that the "hippocampus, a part of the brain critical for learning and memory, is highly active during exercise," he writes.
If you're motivated to make early workouts part of your routine, but love the snooze button, experts recommend waking up earlier gradually. Start with 10 to 15 minutes earlier for a few days, and then slowly start to set your alarm earlier and earlier. Enlist a friend to keep you accountable, and keep in mind it takes awhile to form a habit, so stick with it.
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Disclosure: CNBC parent NBCUniversal owns Bravo.