Free Weights vs. Machines: Which Is Better?

Find out the benefits of using free weights vs. machines for strength training and the best equipment for your goals, fitness level, injury status, and more.

Regardless of your experience level or fitness goals, at some point in your strength-training journey, you'll walk into a gym, scan the equipment throughout the room, and ask yourself one simple yet somehow overwhelming question: "Should I stick with free weights, or should I test out the weight machines too?"

Turns out, there's no clear-cut winner in the free weights vs. machines debate, and both types of strength equipment deserve a spot in your fitness routine. Ahead, learn the benefits that free weights and weight machines have to offer and how to decide which style of equipment is right for you.

Free weights (aka weighted objects you can pick up and move through any range of motion and on any path) may have a straightforward design and no-frills appearance, but they shouldn't be underestimated. Here are the key perks of using this type of equipment — including dumbbells, kettlebells, and barbells — in your strength workouts.

While training with free weights, you’ll not only build strength in your agonist muscle groups (aka the muscles primarily responsible for completing a movement), but you’ll also target your stabilizing muscles, says Alyssa Parten, M.S., C.S.C.S., an NSCA-certified personal trainer, strength and conditioning specialist, and powerlifting coach. These muscles help prevent your joints from rotating — which helps maintain proper alignment and reduces the risk of injury — as you complete a movement, she explains.

Consider a Romanian deadlift: Your hamstrings will drive the movement, but your core and hip adductors will also be activating to keep your joints (your spine and knees, respectively) in a safe position, she says. Stabilizing muscles aside, you’ll also be relying on your grip strength in order to hold the heavy barbell throughout your set, adds Parten. In other words, you’ll get more bang for your buck by using free weights while strength training.

Since you can move dumbbells, kettlebells, and barbells in any movement path you’d like, free weights are generally more versatile than machines, says Parten. During a set of biceps curls, for example, you can turn your arms out to your sides to work your muscles in the frontal plane of motion. Or, you can turn your palms face down once the dumbbell reaches shoulder height à la the Zottman curl, a move that strengthens your forearms. If you’re dealing with muscle imbalances, you can also load the weaker arm more heavily than the stronger one — technique changes that typically aren't in the cards with a biceps curl machine. "You can do a lot of different variations of a movement with free weights, whereas with a machine, most of the time [you’re limited] to how that machine is designed," she adds. "This might help with strengthening and hypertrophying certain muscles that you’re trying to target."

Thanks to that versatility, you’re also able to tweak the movement pattern of an exercise so it feels best for your body. If your shoulders always click or crunch when you perform a kettlebell halo, for instance, you can adjust your technique to make it work for your needs and comfort, says Parten.

Unless you have an entire garage dedicated to your home workouts, you probably don't have the space to store a hamstring curl or chest press machine. Luckily, compact free weights can help you work toward your strength goals without taking over your living room — or eating your entire paycheck. In fact, the Bowflex SelectTech 552 adjustable dumbbells, a winner of Shape's 2023 Fitness Awards, have 15 different weight options, cost a few hundred dollars, and can be used for a variety of exercises. On the flip side, a leg extension and curl machine on its own starts at nearly $450 and requires time and energy to assemble.

Just like free weights, using weight machines (think: the leg curl and extension, leg press, chest press, shoulder press, biceps curl, triceps press, and lat pulldown machines) at your local fitness center can help you build strength and muscle. But the equipment also comes with a few unique benefits.

Since you move in a predetermined path and are often seated while using a weight machine, this equipment better isolates your agonist muscle group and, in turn, promotes muscle hypertrophy, says Parten. "Whenever you want to build muscle size, taking the stability component out of it is going to be beneficial because then you can focus solely on fatiguing that muscle and inducing that hypertrophic effect," she says. For example, performing hamstring curls on a machine will solely target your hamstrings, and you won't need to use your adductors or core strength to maintain proper form and joint positioning, says Parten. "You’re just working the heck out of those hamstring muscles to cause them to grow and adapt," she adds.

Machines can be particularly valuable if you’re dealing with an injury or experiencing discomfort in certain muscle groups while strength training, says Parten. "You can regress certain movement patterns with machines," she adds. "Especially if you have an injury and there's a very specific portion of a movement that causes you pain, a machine might be a good way to still do the exercise." For example, if you feel pain at the bottom of your barbell back squat, you can do a leg press instead and select a seat depth that minimizes the range of motion.

What's more, weight machines can make free-weight movements less complex. Unlike a dumbbell front squat, a leg press doesn't require you to maintain your balance, support weights on your shoulders, or brace your core, says Parten. In turn, it can be easier to concentrate on the muscle you're targeting. (Hi, mind-muscle connection.)

On the same token, weight machines may be safer options for strength-training newbies. While free weights must be held and balanced during training, a machine's weight is fixed to the equipment, so there's no risk of slamming a dumbbell on your toes mid-squat or dropping a barbell on your chest during a press.

Since exercises performed on weight machines better isolate your agonist muscle groups and rely less on your stabilizing muscles, these moves are generally less tiresome, says Parten. Yes, you’ll burn out your quads during a leg extension machine, but the exercise won't fatigue your entire body, as is the case for heel-elevated back squats, for example. That's why you’ll be able to perform weight machine exercises later in your workout than free weight moves, which generally need to be programmed at the top of your training session when you're not so worn down.

When it comes to free weights vs. machines, there's no right or wrong equipment to use. "I think there's a place for both of them," says Parten. "I would use both of them for any client, whether they’re an athlete or general population client." Still, there are a few instances in which it may be beneficial to use free weights in place of a weight machine — and vice versa.

Folks who are totally new to strength training and are nervous in the gym may feel more at ease using a weight machine, says Parten. Machines have pre-set use cases, and they often have instructions on how to properly use them written directly on the equipment, which can calm your nerves and build your confidence as a newbie. The versatility of dumbbells, kettlebells, and barbells, however, can make strength training feel overwhelming and intimidating. That said, "do whatever is most comfortable to you," says Parten. "As you get into a routine and start to feel better about experimenting, [try] learning more free-weight movements."

If gaining muscle in specific areas is at the tippy top of your goal list, weight machines are generally the way to go, says Parten. The equipment's ability to isolate certain muscle groups can help you overload the working muscles and increase hypertrophy — without causing fatigue throughout your body.

To train the most muscle groups with the fewest exercises, you’re best off choosing free weight exercises, which utilize agonist muscles plus the stabilizing muscles, to get the job done. While a leg press will target your quads, glutes, and hamstrings, says Parten, a weighted squat will activate those muscles plus your core and hip adductors, according to the National Academy of Sports Medicine.

Pick up a pair of dumbbells or a barbell, and you can practice the main movement patterns — the squat, hinge, lunge, push, and pull — you perform in your day-to-day life (think: picking a heavy laundry basket off the floor, pulling open a heavy door). Thanks to their undetermined movement path, you can also freely train in all three planes of motion, which helps improve your daily functioning and reduce your risk of injury in the gym and IRL.

Dealing with an injury or mobility limitation? Weight machines that allow you to minimize your range of motion to your comfort level may be a good option for you. That said, free weights can also be valuable, as you’re able to tweak your technique (think: doing a shoulder press with your elbows slightly in front of your body instead of directly at your sides) to prevent aches and pains. Ultimately, both types of equipment may be useful depending on your injury or concern.

The good news in the free weights vs. machines discourse? There's not one type of equipment you should only use during your workouts, says Parten. "If you’re focused on [overall] strength, the top priority would be free-weight exercises — being able to load a movement through the full range of motion using those stabilizing muscles," she adds. "But building muscle is going to be a component of [increasing strength], so you can also tie in machine-based movements." Instead of forcing yourself to use whichever tool is "better," opt to train with the equipment that feels right for your body and helps you meet your goals.