When Does Elon Musk Sleep? Billionaire Speaks of Limits to Fixing Twitter and His Back Pain

But his all-in approach—at age 51—comes at a cost to him personally. 

Since taking ownership of Twitter Inc. in late October, Mr. Musk’s workload has exploded to more than 120 hours a week from as much as 80 hours before, he told investor

Ron Baron

in November at a conference. 

“I go to sleep, I wake up, I work, go to sleep, wake up, work—do that seven days a week,” Mr. Musk said. “I’ll have to do that for a while—no choice—but I think once Twitter is set on the right path I think it is a much easier thing to manage than SpaceX or Tesla.”

Mr. Musk didn’t respond to a request for comment.

Tesla investors have expressed concerns Mr. Musk is distracted with Twitter, and some have urged him to step back from running it. He has promised to eventually bring in a Twitter CEO and has brushed aside criticisms that he isn’t engaged with other parts of his business empire, saying he hasn’t missed a single important Tesla meeting. The auto maker earned a record profit during the final three months of last year. 

“I still do a lot of work at Tesla!” Mr. Musk tweeted in November. “Was at our Palo Alto engineering office until late Thursday night when I had to redeye to NY.”

Nevertheless, Mr. Musk said last month he can only do so much, in response to criticism on Twitter over an issue with the social media platform in India.

“First I’ve heard,” Mr. Musk wrote on Twitter. “It is not possible for me to fix every aspect of Twitter worldwide overnight, while still running Tesla and SpaceX, among other things.”

Even before buying Twitter, Mr. Musk wasn’t a “chill, normal dude,” as he once joked on “Saturday Night Live.” Mr. Musk has said he usually goes to sleep around 3 a.m. and typically gets six hours of shut-eye before waking and immediately checking his phone for any new emergencies. 

These days, Mr. Musk has said he is sleeping at Twitter headquarters in San Francisco. He has even provided beds for employees. 

His schedule has become part of the man’s myth. Last month, a fan on social media marveled at Mr. Musk’s single-day itinerary: He testified in a lawsuit that morning, attended a Tesla event in Nevada that evening and then met with Tesla’s artificial-intelligence team late into the night.

Mr. Musk chimed in with a tweet, writing: “And then was at Twitter HQ past midnight. Very long day.”

For years, Mr. Musk has talked about struggles with sleep as well as back and neck pain, challenges that have drawn attention during other intense periods.

Concerns about Mr. Musk’s health had circulated a few years ago, ignited by photos of him that appeared to show a new scar on his neck. In 2020, he confirmed he had two surgeries, the first a failure, to address neck pain.

His pain, Mr. Musk has said, traces to a birthday party thrown years ago by his second wife that was attended by a sumo wrestler.

Mr. Musk took to the ring and—according to him—managed to throw the 350-pound opponent, resulting in an injury to his spine. “It cost me smashing my c5-c6 disc & 8 years of mega back pain!” Mr. Musk said on Twitter last year.

His troubles sleeping drew public attention in 2018 amid the dust-up that followed his efforts to take Tesla private. That year, the car company was also struggling to increase production of the Model 3, leading Mr. Musk to sleep on the factory floor.

His use of sleeping aid Ambien attracted attention, in part because he joked on Twitter about its use as part of efforts to relax amid a busy schedule: “A little red wine, vintage record, some Ambien…and magic!” 

Entrepreneur

Arianna Huffington

at one point in 2018 pleaded with Mr. Musk to take better care of himself. Ms. Huffington is the author of “The Sleep Revolution,” a book that explores how a lack of sleep can compromise health and hurt decision making. 

“People are not machines,” she told Mr. Musk in an open letter. “The science is clear. And what it tells us is that there’s simply no way you can make good decisions and achieve your world-changing ambitions while running on empty.”

Photos: How Elon Musk Made His Fortune

He responded with a tweet sent at 2:32 a.m.: “Ford & Tesla are the only 2 American car companies to avoid bankruptcy. I just got home from the factory. You think this is an option. It is not.”

He still has been dealing with controversy from that period.

Last month, when he complained about back pain, he was in federal court in San Francisco testifying about tweets he sent in 2018 claiming to have secured funding to take Tesla private. It later became clear the funding had not been finalized. 

Mr. Musk was sued by shareholders who claim they were misled by the tweets into money-losing trades. On Friday, a jury found him not liable.

After his win, his mother, Maye Musk, congratulated him on Twitter. “Such a relief,” she wrote. “Now catch up on sleep.”

Write to Tim Higgins at [email protected]