Should You Use Free Weights or Machines at the Gym? | GQ

The fitness world is divided: On one side, you’ve got the purists who swear by barbells, dumbbells, and kettlebells. This crew is all about functional strength—workouts that mimic real-life movements and hit multiple muscle groups. It’s one of the best ways to build overall strength, improve coordination, and develop strength in greater ranges of motion.

But then there’s the flip side: The undeniable popularity of machine workouts that primarily target one muscle at a time—think cable stacks, leg press, or the trusty Smith machine. “Isolation is huge right now, especially with influencers,” says Nate Rodgers, ISSA-certified personal trainer at LifeTime, who are looking not just to grow the glutes but also to bulk up for a desired physique.

The first group of people might be quick to dismiss machines as tools for bodybuilders or people chasing aesthetics, but it’s a bit more complex than that. Surprisingly, studies have found little difference between muscle and strength gain between free weights and machines.

No matter your goal, nearly every piece of workout equipment in the gym serves a purpose—except for maybe that rotary torso contraption that has you kneeling while awkwardly twisting your lower half side to side. According to Dr. Rob Butler, biomechanics expert and director of implementation science for Uplift Labs, the key is knowing your goals before you plan your session.

Free weights shine for compound, functional movements—deadlifts, squats, lunges, and so on—that recruit multiple muscle groups. They’re also great for building strength through exercises like shoulder presses, bent-over rows, and farmer’s carries. “The biggest difference when we talk about functional movement is there tends to be more bodyweight stabilization with it—it’s more total body,” Butler explains. As you lift a heavy barbell or step into a lunge, your core and upper body are firing, too. Basically, you’re getting more bang for your buck and you can program shorter workouts that hit a wider range of muscle groups.

Free weights also mirror real-life movements. “Functional exercises allow you to create more body awareness and help you improve your mobility, improve your longevity,” says Rodgers. Deadlifts mimic picking up heavy boxes, squats resemble sitting in a chair, and kettlebell swings are like throwing around your giggling toddler. “The general population just wants to be better members of the community, be active, be parents, be brothers, sisters, play in the park,” says Butler.

Plus, for older adults, free weights can actually help counteract age-related decline of motor functions and reduce risk of falls. A 2019 study found that leg strength improved by a staggering 113% over 26 weeks of training compared to a 44% increase from machines. (Studies researching younger adults don’t find significant differences.)

Another surprising benefit? If you want to boost your testosterone, free testosterone (the active form of the hormone) increased more in men that used free weights than machines in a 2020 study in the Journal of Strength and Conditioning Research.

The drawback is that free weights come with a greater chance of injury if you’re using improper form or don’t have a spotter when lifting heavy. That’s where machines come in.

Machines are thought of to promote a more aesthetic build, rather than developing strength and power. The funny thing is, though, that most studies do not find any difference in muscle hypertrophy (increase of muscle mass) between the two training modalities. That being said, machines are good for a few things: isolating muscles and staying safe without a spotter.

Since it’s a lot easier to target a specific muscle with a machine, athletes can use machines to work on a weakness. If you have problems with your rotator cuff, you can use a cable machine to perform rehab exercises like external rotations to work these muscles without putting stress on the rest of the shoulders. (Always consult with your PT first, though!)

When you’re using machines, you also reduce the recruitment of the surrounding stabilizing muscles. Take bench presses: With free weights, you need to activate more of your deltoid muscles to hold the barbell steady than if you were to use a Smith machine, especially as you creep toward your one rep max.

If you’re already experienced in the gym, free weights may give you a slight advantage, but if it’s your first time bench pressing, “machines are a great tool to start off with,” says Rodgers, because they guide you through the movement. Many have stops to prevent you from going outside of your natural range of motion. Your form is more controlled, which means less risk of injury as you build strength.

Machines, when used intentionally, can also build body awareness that can help you transition to dumbbells or kettlebells. “A shoulder press machine is going to emulate the same range of motion that you need for dumbbell shoulder presses, right?” says Rodgers. “When you understand the way your body moves and what you have to engage in order for you to lift, it’s a lot more transferable when you do get a free weight in your hands.”

If you make the switch from machines to free weights, you’ll have to go lighter at first. “We forget that the body is a weight,” says Butler. “It’s definitely not a one-to-one correlation.” Find a weight that you can do 12 to 15 times really easily, he recommends. Make sure there’s no pain or discomfort and that you can get a full range of motion through your reps. From there, you can scale up.

Don’t be afraid to mix and match in one workout, either. You can use free weights at the start when you’re fresh and move to the machines when you’re fatigued or want to work smaller muscle groups. And if your spotter stayed home? Don’t let your ego get in the way—just use the Smith machine.

While it’s tempting to throw shade at the person at the gym who cycles through machines as they scroll on their phone, looking like they’re barely breaking a sweat, the most important thing is just staying consistent. “Activity should put us in a spot where we want to continue tomorrow,” says Butler. “So if you love free weights, you should do free weights. If you love machines, you use machines. Whatever gets you inspired to move.”