A lot has changed since the third season of Stranger Things premiered in the summer of 2019— especially for David Harbour. The actor, who plays the burly father figure Jim Hopper on the Netflix hit, lost over 70 pounds (!) in preparation for his big reveal in the latest season when—spoiler alert!—after surviving a massive explosion, Hopper emerges locked up in a Soviet gulag, looking mean and lean. 

The transformation wasn’t just a physical one. When the pandemic hit and filming stopped, Harbour incorporated long runs into his workout routine, which he says helped both keep the weight off and his anxiety. Through the process, he says developed an entirely new relationship with his body and mind. GQ caught up with Harbour to talk about how he dropped all that weight, partnering with the hardcore running brand Brooks, and how all this physical activity has helped him feel more sane.

For Real-Life Diet, GQ talks to athletes, celebrities, and other high performers about their diet, exercise routines, and pursuit of wellness. Keep in mind that what works for them might not necessarily be healthy for you.

GQ: For the latest season of Stranger Things you went through quite the transformation. How many pounds total did you lose and what was that timeline like?

David Harbour: I think the total was like 75 pounds. I started out like 265 and went down to 190. The timeline was sort of strange because the pandemic interrupted it. I lost the big bulk of it in about three months. I lost like 45 or 50 pounds in 3 months, and then the rest was a slow burn. Another four months and I had to maintain it for a year while we were waiting to shoot again. It was funny: When I started, it was sort of easy. As you lose more and more weight, it’s much harder because your body is like, we gotta stop doing this. But in the beginning it was liberating.

During those first three to four months, what did your day-to-day eating and workout routine look like?

I did a lot of intermittent fasting, which I know is sort of the diet of the moment, but it really did work for me. I don’t know if it’s just code for starvation but it’s basically like… I was hungry a lot of the time. In general I think it’s calorie intake, calorie outtake. I don’t think there’s anything that much more mysterious. But it was fun to have this fetish, this intermittent fasting. We would do like six hour windows and like two days a week I would do 24-hour fasts because I started to get more and more intense.

I would do a mixture of resistance work and cardio. The cardio was a lot of running but with very low intensity over an extended period of time, around 60 to 90 minutes at a heart rate of about 165. That was something that was en vogue a while ago, but now everything has become high-intensity training and that that kind of working out has lost its luster. But I’ve found that not only did it help me physically with losing weight, but also mentally. It really helped with my anxiety and my breathing rate. You get about 40-45 minutes in and my breathing would just slow down and I just became more relaxed.

I did a lot of Pilates too, and some weight training. What I was looking for was that lean look. He’s strong but he’s been emaciated, so the Pilates really helped with that lean thing, like strengthening, lengthening, and stretching the muscle a lot.

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It’s funny how you describe intermittent fasting as just code for being hungry. During those windows, what food were you eating?

You know, in the beginning I wasn’t changing my diet at all. I would just fit it into the window. Because I was so, I guess, unhealthy. I was like 270 pounds and I was just eating whatever I wanted. My knees were shot. I was in a bad way. So I would not eat until noon and I would stop eating at 8 p.m. I would eat whatever I wanted I would eat burgers and pancakes but I still lost weight because of the time window. As time went on, I would see results and I’d get excited about it. I was like oh, I wonder how far I can push this.

There’s a fine line between an eating disorder and how far you can push. You don’t want to go too far, but I did find myself going , like: Well if I eat healthier, if I cut out a lot of meat, things that have dense calories… I was eating a lot more vegetables and less sugar. You sort of hit these plateaus and you have to clean up your diet. So you get cleaner and cleaner. By the end, like right before we shot that scene, I was eating basically, like, cardboard. 

I think the real treat was my trainer letting me have a rice cake… like mmm cake! Let me savor this… [Laughs]

When that day on set finally came to shoot the reveal, how did it feel after putting in all that work and time to transform your body?

It’s pretty exciting to be able to do the work I do in general because we get to live in other people's skin. There was something about me when I looked in the mirror that was me, but it was something that I’ve never seen before. I’ve never, as an adult, been that thin and so it was exciting to see Hopper having gone through this experience to see a different skin.

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I know you have a new partnership with Brooks, which is a serious running brand. Have you always been into running long distance?

No. No. [laughs] When I was a kid I would run a little bit. The funny thing about me is I became in my thirties, sort of—very—unathletic. My idea of a workout was getting off the couch and getting a bag of pretzels. So the interest in fitness has been a relatively new thing. Around age 43, I was sort of broken. My knees were kind of shot and I was carrying around all this extra weight. I was busted. I just thought that life, as you age, you just sort of get busted. I think I found by pushing myself and making a real mental shift, that as I got into it—not in the beginning, the first couple months were hard—I started to crave it. It started to be a new relationship with my body that I hadn’t had in a long time.

Running was a big part of that because it allowed my mind to quiet. It gave me this freedom from the phone and this freedom from constant stimulation and activity. You’re just out there and your breathing slows down. There’s just this meditative quality to it. I’ve never been a good sit-down mediator but there’s something about it, where you push yourself and just let yourself go. 

I don’t take it very seriously. I’m not a serious runner. I’m not a guy trying to push times. It’s almost embarrassing how slowly I run. There are children playing much faster. But there’s something about it that’s for me. I’ve found that my heart is stronger. My doctor is really happy with a lot of the results I’m getting back. I feel younger. That’s what this Brooks partnership and campaign, “It’s Your Run,” is about, celebrating all types of runners. You’re right that a lot of serious runners rely on Brooks and their gear, but their shoes and such are for anyone who runs, and I respect that.

In 2018, you opened up about being diagnosed with bipolar disorder. As an avid runner myself and someone who was diagnosed with bipolar in my late teens, I can relate to a lot of what you’re saying about the mental health benefits.

Mental illness is such a strange thing. It’s very hard to define. I think we try in the medical community to define it but it’s basically sanity or the ability to exist in the world untroubled. And that’s very hard for me to do because I think my nervous system is tuned to a certain way and I think the things that make me an artist are the same things that make me mentally ill. I think my tuning fork is just a little too sensitive or a little too something. Acting has been something that works in both departments for me. It’s something that fires me up and also relaxes me because it gives me an outlet to express this stuff that’s going on.

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I’ve found that running has all the benefits of that, without the risk. Acting can take you to these places that overstimulate your nervous system but there’s something about running. I don’t know, maybe if I get into running too much and start going fast, maybe it will be a problem. But there’s something about this slow repetitive movement that brings about a sanity. It just feels like something we’ve been doing for tens of thousands of years as a species. There’s something about being in nature when I can and just the rhythms and the meditative qualities that really does slow down my brain. I’ve found that it made me saner. I feel saner.

Are you typically running with music or is it just you and your thoughts?

It’s pretty 50/50 or 70/30. I do love music when I run. I really like similar food and similar music. Sometimes I’ll get into a song and I’ll just listen to it over and over again. I put it on repeat while I run. There’s something really satisfying about that. 

What’s on repeat right now?

Oh God. It’s so embarrassing to talk about my musical taste. I go back to stuff from the 90s that I listened to growing up. I’ve been listening to a lot of Natalie Merchant and the 10,000 Maniacs, which I’m sure you don’t even know because you seem much younger than me. [Laughs] but they were a band in the 90s and I loved them in college so I listen to a lot of that.

You mentioned Pilates, which I think people would be surprised to hear that you did in your routine. What about that workout does the public not know? Would you recommend it?

The funny thing about me as an actor is that a lot of people see me as this rugged Jim-Hopper-y type guy, or Red Guardian, but you know, I am an artist, actor—like, weirdo. So when I was in school growing up I used to dance. There’s something about Pilates that is like strengthening and stretching. A lot of ballet people do it. I think it’s something where it allows your instrument to be strong but also expressive. I think that’s why dancers are drawn to it. One of the things I’m always trying to do is push the boundaries of expression with my instrument. Be able to as an actor have you see things in little behaviors and gestures that I do. When I do weight lifting I feel a little more locked up. Like there’s armor on me. There’s something about Pilates that feels like you’re still exposed but you’re strong.

How does your average diet compare to what you were doing during this weight loss process?

I mean, I still try to do intermittent fasting. They call it a lifestyle thing. I do like to do it. I like to not eat breakfast and not start eating til 1 or 2 p.m. I have better days and worse days. Most of the time, I try to stay within that Michael Pollan ideal of mostly vegetarian with a little bit of meat. It’s something that's good for the longevity of the species and the earth and it just feels right for my body. I also have my days where I just have to grab the Nutella from the cupboard and go in with the spoon. So, you know, I’m not a perfect person.

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How do you take your coffee?

Black. I love black Americano. I love strong black coffee. It tastes like bitter madness to some people but I just love it.

As someone who thought your body was resigned to ache a certain way as you got older and reached the light on the other side, what words of advice do you have for people who are looking for some motivation?

I thought I needed knee surgery and toe surgery. All these things. I’ve been such a Western medicine kind of guy. You know: you get surgery, or a pill. There’s something about physical rehab that I never took seriously and I really went into it because I was at this point where I didn’t want to get a new knee. And I found that it was extremely effective. So I would say if you are having problems and there is some sort of physical rehab, to do that. The other thing is to just keep going. On the days you don’t really feel like doing anything you could just walk. Just lift a couple heavy grocery bags. Just stay physical and stay in your body. That consistency does help develop a mindset of your body not being alien to you and still something that you live in.

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