David Harbour Stranger things transformation

David Harbour Explains How He Lost 75 Pounds

The ‘Stranger Things’ star used intermittent fasting, pilates, and kettlebell training to achieve his most drastic physical transformation yet.

David Harbour is no stranger to jaw-dropping transformations. We’ve seen the Stranger Things actor get fearsomely jacked for his role of occult-battling demonic hero in Hellboy, and cut weight for his role of the “Red Guardian” in Black Widow.

Most recently, the 47-year-old actor lost a staggering 75 pounds in eight months for his role of Jim Hopper in season four of Stranger Things, only to gain it all back to play Santa in the upcoming holiday thriller Violent Night.

“All told it was a difficult and exciting ride,” Harbour says. In his latest Instagram post, he opens up about the brutal transformation process.

In Harbour’s following IG live with his celebrity trainer, David Higgins, the two divulge how he handles playing yo-yo with his weight, and how his fitness, diet, and body image have changed.

Here’s everything to know.

His Weight Loss Journey

“I’ve gone through phases of my training for various roles, but never as intense as this,” he says of the process. “It was a daily battle.”

And the battle wasn’t always straightforward: Harbour dealt with weight fluctuations. “Everyone assumes weight loss is linear,” his trainer Higgins chimes in, “it’s undulating, you go up and down.”

Over the course of eight months, Harbour stayed the course. “It’s like building a house. If you knew how hard it was from the start on day one you might not do it,” he says, “But when you do it brick by brick, it’s fun and you come to enjoy it.”

His Fitness Routine

On fitness, Harbour admits, “My body has never been my favorite thing. I never played sports, I was a nerdy kid reading books and playing video games.”

So training was foreign. Over his years as an actor, he’s worked to build what Higgins describes as “physical literacy. My body can do what I want it to do now,” says Harbour.

For this particular transformation, he turned to daily training sessions with Higgins to burn calories and tone up. Steady-state running, kettlebell training, and Pilates were all on the menu.

As they got started, Harbour put in one-hour daily sessions on the Pilates reformer. His goal was to increase muscle activation and clear up existing injuries. “I thought I needed knee surgery, but after a few months of pilates-based exercises, I didn’t have aches in my knees or hips anymore.”

Then the pandemic hit mid-production of Stranger Things season four. Production stopped in its tracks, but Harbour had to maintain his progress for right around a year until they began shooting again. “You were dialed in, nothing was stopping you,” recounts Higgins.

“I began doing an hour of steady state running every day,” says Harbour, “around that time I was feeling the stress of the pandemic, and running helped to regulate my breathing, and calm my anxiety.”

His Diet

Before his transformation, Harbour was eating a lot of sugar, which he notes was terrible for his mental health. “After a few months of eating healthier I felt the benefits start rolling in,” he shares, “I felt steadier.”

He also relied on intermittent fasting to speed up the weight loss process. Intermittent fasting is the practice of eating all your food in a specific window of time throughout the day. Harbour shares he used 18-, 24-, and 48-hour fasting schedules to get results.

The 18-hour fasting window was Harbour’s favorite, “My body responds really well to it,” he says. The 24- and 48-hour schedules were more challenging, which he recounts as, “rolling phases of tremendous hunger, and tremendous clarity.”

These drastic fasting measures weren’t Harbour’s first choice, especially because he was fasting while looking to put up his best performance on camera for Stranger Things. However, some things must be done for “the old shirtless day,” he says.

His Outlook

“I struggle with my own narcissism,” he admits, when discussing body image. “I look at myself in the mirror a lot more now, something I never do when I’m big.”

But through years of changes Harbour has had to come to terms with his body in both states—thick and thin. “There’s a certain power and fierceness in the thin, lithe body, and something jolly about being bigger,” he says, “But it is such a fun part of the job to live in a different version of your skin for a while.”

After recently ballooning up to play St. Nick in Violent Night, this perspective has helped him stay grounded. “All the concern about perfection is a waste of time,” he says, “The beauty that people should respond to is the beauty within us.”