Gunnar Peterson and Daviv Beckham at F45 for DB45 Workout

Hollywood is Ripped Because of Gunnar Peterson. Here’s His Playbook

We talk to the celebrity trainer about his new David Beckham functional workout and why he’ll never give up tequila and peanut butter cups.
By Sean Evans
July 3, 2024

It’s faster to list the celebrities that Hollywood’s elite trainer Gunnar Peterson hasn’t worked with. 

Scroll the 59-year-old Texan’s Instagram account and you’ll lose count of recognizable famous faces: Dwayne “The Rock” Johnson thanks Peterson for heavy dumbbells he’s dubbed “my Kevin Harts,” a 75-year-old Sly Stallone shows a bulging bicep most 30-year-olds can’t achieve, Bebe Rexha wearily perches over a vomit bucket post-session; Kate Beckinsale nails inverted sit-ups, Lindsay Vonn crushes one-arm dumbbell snatches, Peterson’s on the hardwood, prepping the Lakers, or just hanging with King James

And there’s Mark Wahlberg, welcoming Peterson to the F45 family, after Peterson became the Chief of Athletics for the burgeoning functional fitness franchise (Wahlberg owns 26 percent of F45, by the way). 

The most recent celebrity splashed across Peterson’s feed? David Beckham. The soccer god partnered with F45 to create a high-intensity, functional workout program modeled after Beckham’s workouts which helped him remain at the apex of his sport well into his thirties. The architect of the DB45 workout

Gunnar Peterson, naturally. 

Gunnar Peterson and David Beckham at an F45 for DB45.

Beckam’s DB45 F45 workout involves “explosive, power-focused, multi-directional exercises” packed into a 45-minute workout, per the company. There are two sets to complete at each station, and you progress in a “football-inspired 4:4:2: class formation, with stations representing typical football positions including Goal, Defense, Mid-Field, and Attack.” 

The timings of each set are a cheeky nod to Beckham’s famous jersey numbers from his career, with “32 seconds work, 15 seconds rest, and 23 seconds work, followed by 20 seconds rest. Users will complete the ultimate finisher with 7 x 30 second bodyweight exercises.” 

We chat with Peterson about working with Beckham to assemble the program, why Peterson loves functional training so intensely, whether or not celebrities are in better shape simply because they’re rich and famous, working out past the age of 40, his fondness for Reese’s Peanut Butter Cups, and why he tests his blood regularly. 

The Edge : Congrats on your new role as Chief of Athletics for F45. What’s that role entail? 

Peterson: It entails whatever they want. [Laughs] I’m a huge fan of the F45 product itself. I think it’s the future of fitness. Other than the niche population of bodybuilders, I’m seriously wondering why everyone doesn’t train [with functional fitness]? It’s efficient, it’s great for body composition change, and it’s great for functional health, since you’re moving in all three planes of motion.

You have your pick of programs and gyms to partner with. What about F45 drew you in the most?

Everything you do in an F45 class prepares you better for what you experience in real life, and I love that. It makes so much sense. F45 takes the guessing out of a workout. It’s all regimented, so you get to an F45 and you know the room, you know the workout, and you can exhale and know exactly what you need to do. 

Knowing what to do is sometimes the larger part of the battle at the gym. 

I give everyone credit for being in the gym. Kudos to anyone who goes, because it’s not easy to even set foot in there. But I do watch many people mill around and haphazardly knock out a set here and a movement there. I see people who’ve been in the gym for an hour or more and only do seven things. I watched a guy recently using a shoulder raise machine while looking at someone on a treadmill. Dude, focus! I want to shepard these people out the door and into an F45, where they can do 27 things in 45 minutes. 

How important is efficiency when you think about working out and building programs? 

Very. The one commodity we can’t recreate is time. You get the same 24 hours that everyone else gets. Training in a manner where you’re responsible to time, using your session judiciously, you get those same benefits and you can have the rest of your day back to tackle your responsibilities. 

David Beckham doing his DB45 routine at an F45 facility.

How did you approach designing the David Beckham DB45 program? 

It’s so fun. It harkens back to workouts and movements David did as a footballer. Things he loves—and things he didn’t love but knew would make him a better player and person. A lot of fun hand- and foot-to-eye movements. He loves fast feet, footwork drills, all multidirectional, using various planes and circling around. David was known for great footwork and his training regimen helped with that.

You mentioned stuff he doesn’t like, too. What does David hate? 

[Laughs] Any smart athlete plays those close to the vest. Talk about moves you hate and a sadistic coach will implement those. [My celebrity clients] will rarely say ‘I hate this machine’ because then they hear, ‘yeah? Let’s do two more.’  

To answer your question, maybe some of the explosive movements. I took the DB45 class in London last week and there’s a big barbell hang-pull. You’re hanging from the knees, popping your knees through and pulling up. People see it as an upright row, but it’s a hip-drive and your hands guide the bar. By the time it reaches midchest, the bar should be weightless. I don’t know that David loves those movements, but he understands how that explosive power translates.

How did you work with David to craft the program? 

Six months ago, we met in London and we went through his likes and dislikes, setting the groundwork for the program. At the end, he casually says, ‘I want it to be the best workout.’ And I responded, ‘no pressure.’ And he just gave me this smile. David’s a top shelf guy. If you look at his career as a player, he has a ton of top-tier accomplishments. He only aligns with top brands. I respect that he loves F45, and that he wants his involvement with the gym to be top tier, too. He’s not a guy who just throws his name on something; he was actively involved in the program, bringing a concept and a way of execution to the table from the start. 

How high are David’s standards for a workout? 

High. But that’s more fun and challenging trying to meet those standards. It’s titillating that the guy you’re working with is so hands on. I’ve done work with [celebrities] who are prepping for a movie role and we go to talk about the routine later, during press time, and they don’t care what you say when you’re representing them; they don’t care about the workout. David’s the opposite. He’s not phoning it in, just doing the Queen’s wave.

David’s 47. Many of your clients are in their forties. What’s the most effective workout for men over 40 who are looking to lose body fat? 

F45. If you want to stay in the game, physically, it’s ideally a program. You need a mix of cardio and strength workouts during the week, and some hybrid workouts over the weekend. This way, you’re dialed in and you don’t risk the weekend warrior pitfall of overtraining. You need some macro level programming; you can’t just do bench presses repeatedly. 

What’s the secret for building muscle after 40? 

F45. Again. [Laughs] Resistance training or training under load, in some way, shape, or form. You can be an old school gym rat, you can body weight, but you have to resistance train. The key to sticking with it is variety. Use sandbags, dumbbells, a push-sled, whatever. With resistance or load training you challenge the metabolic demands of muscle. 

Next, you need to look at diet. Are you eating properly? Are your macros dialed in? If you’re training properly—with enough resistance in your overall programming—you need to maintain the lean tissue you’re working hard to acquire and that comes with a good diet. Shoot to keep to your diet 100 percent; then you’ll end up at 85 and be okay. Shoot for 85 percent, you’ll end up at 65 percent and that’s an F where I came from.  

Lastly, rest and recovery. Sleep is the sleeper that people never think about. It should be the easiest box to tick; get more sleep, you’ll be leaner. You can maintain favorable body composition by giving yourself the down days to rest.

Love that you mentioned diet. What’s the best diet for aging guys? 

I would send you to a nutritionist to test your body to see what it handles and processes most efficiently. If you have a very sensitive lactose intolerance trigger, you can’t pound protein shakes. It’s funny; I was at a conference and a guy was asking a nutritionist about being dairy-free then mentioned he takes whey protein. …You’re not dairy-free, pal. 

I’m not going to tell you to go full-plant based, or something. Go to a professional and look at your blood. They’ll tell you what you break down well, enzymatically. Then you make choices on your food. I don’t have a problem with protein and fat, so I stay with that. I don’t fear carbs. I eat complex as well as simple carbs every day. I know where my body will use them, and what my calorie threshold is. 

Do you adhere to a specific meal plan? Are you mostly plant-based?

I’m not plant-based. I’ve done raw, vegan, vegetarian, and pescatarian. But now I eat whatever. I can see how it all affects me, but I’m going to have a tequila and Reese’s Peanut Butter Cups — without apology. I’ll take my F45 class the next day and be fine. It’s okay if one of the wheels comes off. Now, if you missed your workout, your food is bad, your rest and recovery is subpar; that’s a problem. If you’re in a four-wheeler and one of the tires is flat, it’s easier to limp along.

How often do you personally test your blood?   

More than three times a year and I could benefit from doing it more. I’ll go in and ask for a men’s health panel and have it run. 

What do you say to guys who are adverse about getting their blood or hormone levels tested? 

Even the race car has to go to the mechanic once in a while. You have to do that. Without diagnostic testing, you’re shooting in the dark. Not that you may not still hit the target, but with testing, it makes it easier to achieve your exact goals. Your body is a machine and you owe it to yourself to look under the hood. You don’t want to get caught with Stage 4 anything. Check your [blood and hormones] early and as often as you can so you know everything is truly paying the dividends you believe it to be. I know people who monitor their food and become social weirdos who leave parties at 8:15 to go home and get a full night of sleep, but they resist bloodwork. Why? 

Has routine testing uncovered anything that changed your approach to diet or fitness? 

Yes. My cholesterol snuck up into the 180s. So I owned it right away, made dietary changes, and I’m back in the driver’s seat and it’s down to normal. But it climbed up quickly. I don’t know that it would’ve evolved into something bad, but that’s how [bad situations] always start.

Take a page out of Gunnar’s playbook and test your hormones with Hone’s at-home assessment kit. Ready to know what’s happening inside your body?

You train a lot of celebrities. When people look at famously chiseled bodies you helped craft, many say it’s easy for celebs to get ripped: they have time, money and better access. What do you think? Is it easier to be healthy and fit if you’re famous? 

No. Regardless of the trainer, myself included, the credit [for that body] goes to whomever is putting in the work. A good trainer makes it more efficient by sequencing workouts in a beneficial way or by knowing when to say let’s have an off day. The programming is the trainer; the execution is the [celebrity]. It’s not easier being fit when you’re famous. The people I’ve worked with have so many things pulling at them; the demands for their time are incalculable. 

I trained Khloe [Kardashian] for years and we worked on [her reality show] Revenge Body. Those were real people who got trainers, nutritionists, and were given plans to follow. All they have to do is work the system. One woman quit. One dude was kicked off the show. They couldn’t do it. You have everything coming to you, exactly what you need, and you still can’t maintain your program. 

That speaks to you as a person. If you’re a dedicated person, being fit may be easier. If you’re not that person, it’s no easier if you’re famous.  

Finding My Edge: The One Thing…

What’s the one thing you wish you knew about staying healthy and fit in your 30s?

I wish I had paid more attention to rest and recovery protocols.

What’s the one thing you always have to do when working out?

I have to plan it out before I get there. It’s not a whole ominous routine; more like doing this much cardio, this much stretching, then these exercises.

What’s the one thing you tell yourself on a day you’re not motivated to work out?

I look at my kids. That’s the easiest [motivator] in the world for me. I don’t want to be the guy who has to get off the field. I want to play with them for as long as I can.

What’s the one thing you always have in your fridge?

Salmon. Not lox! The smoking alters the macronutrients too much

What’s the one thing you have every day?

Grilled salmon. My clients know it. My parents know it. I do a food share delivery, and have for 20 years. I just get salmon, every single day. Wild, if possible.