The Best and Worst Machines to Use at the Gym, According to Trainers

Exercise machines can serve a role in an effective strength-training program, but some are much more beneficial than others.

I've been coaching clients in person and online for more than eight years. My thoughts on machine training have undergone several big shifts during this time.

In the early days of my personal fitness journey — before I began working as a coach myself — I used machines all the time. I didn't know how to properly use free weights and felt very insecure in the weight room. Machines provided a simple solution to help me build basic strength and confidence when I first started working out at the start of my lifting career.

Over the years, I learned more about functional training and stopped using machines. Because they isolated muscles and didn't mimic real-world movements, I believed machines were worthless at best and dangerous at worst. I never used them with my clients and actively discouraged others from including machines in their training.

Today, I take a more nuanced approach to machines. I think they can absolutely be beneficial for some folks in certain settings. However, for others, machines may not be the best choice.

You might consider using machines if:

• You're brand new to the gym, don't have a trainer and want to focus on simple exercises that are easy to perform.
• You're returning to training after an injury and your physical therapist or doctor has instructed you to use machines.
• You have difficulty getting up and down from the floor, lying on an exercise bench or performing standing exercises.
• You're trying to build muscle. Machines can sometimes help you hit different muscle angles in ways that free weights cannot. It's also easier to perform certain intensity techniques (such as drop sets) using machines.
• You don't have access to free weights, but you do have machines available. This is often the case at condo and hotel gyms.

Most gyms provide a variety of different machines. Many of them are useful, but coaches generally recommend staying away from four specific machines unless you're an advanced trainee using them for a very particular purpose.

The back extension machine is designed to build strength in your lower back. You sit on a machine designed much like a chair with a pad behind your upper back. You lean back against the pad, using the strength of your lower back to move the weights.

Trainers don't like this machine because it places unnecessary stress on your spine without building the type of lower back strength you need to feel great and perform well at the gym.

It's pretty unusual to move loads by utilizing only your lower back. Rather, your low back typically performs a stabilizing role and helps transfer force between your powerful, mobile hips and your upper body. Isolating your lower back using this machine won't do much to help you build a stronger core and may exacerbate pre-existing back pain.

Instead of using the back extension machine, try using the 45-degree back extension machine. This is a piece of equipment that helps angle your body as you stand in it with straight legs, allowing you to bend down at the hips or waist.

You'll train your back in a similar way, but with more assistance and protection from your hamstrings, glutes and core. You can also build this kind of strength in your back using hinging movements, such as Romanian deadlifts and bent-over rows. If you don't have access to weights or machines, try superman exercises, which strengthen your lower back, glutes and hamstrings.

Think of the ab crunch machine as the opposite of the back extension machine. While the back extension machine targets your lower back and core by bending backward, the ab crunch machine targets the same muscles using a forward bend.

If you spend much of your day sitting at a desk, this may cause your spine to flex (round) and your shoulders to slump forward. Hunching forward itself isn't a problem.

However, when you spend all your time in this posture and then go to the gym and also load it up with heavy weights, your lower back and shoulders are probably not going to feel very good. Your ability to safely perform other exercises, such as deadlifts and overhead presses, can also be affected.

Building a stronger core can counteract the effects of sitting. However, there are much more effective methods to do so than using this machine.

In fact, Roth says it's a misconception that using machines is the best way to train your core. Instead, he encourages his clients to focus on engaging their core properly during compound movements like squats, rows and deadlifts.

Additionally, exercises such as planks, dead bugs, Pallof presses and loaded carries (like the farmer's walk) are dedicated core moves that focus on resisting movement through the torso and essentially work the opposite of how machines do and in a manner much more in line with how your core actually works.

It's OK to occasionally perform sit-ups, crunches and other exercises involving spinal movement, but you're better off not loading up these movements with external weight on a machine.

The rotary torso machine — where you sit down and twist weights from side to side — ostensibly targets the oblique muscles on the sides of your torso. However, this machine is actually rather ineffective for building a stronger core.

Your obliques do help rotate your torso, but their main functions are to stabilize your body while moving heavy loads and to transfer force from side to side as you walk or run. If you want to build strong obliques, focus on side planks, Pallof presses, loaded carries and single-arm and leg-free weight exercises.

Roth doesn't like the rotary torso machine because it places an unnecessarily high amount of torque on your spine. Your lower back (lumbar spine) only has a few available degrees of rotation. It therefore doesn't make sense, and is potentially dangerous, to twist your spine around under load, especially given the limited potential benefits of using this machine.

If you want to include rotational training in your workouts to help improve athletic performance, focus on exercises that drive rotation from your hips as opposed to your waist, such as rotational squats, presses, lunges with twists and med ball throws. You'll be stronger and more powerful, and your lower back will thank you.

The adductor/abductor machine is designed to isolate the small muscles on the inside and outside of your thighs. You sit on a chair-like machine and use your knees to either push the pads out and away from your midline or in toward your midline.

The problem with this machine is that you almost never use these muscles in this way in the real world.

How often are you sitting down driving your knees in or out under load? The answer is almost never. On the flip side, you rely heavily on these muscles when you're squatting, lunging, riding a bike or playing sports. They must be strong and able to resist high forces from multiple directions otherwise you'll fall over or your form will suffer.

"To strengthen the adductors and abductors, most people would need to be challenged in a plane of movement that forces them to balance, stabilize themselves and recruit these smaller muscles," Farrell says. "Being in a seated position while passively driving the knees inward and outward completely overlooks this important aspect of strengthening these muscles."

Some machines can be incredibly useful in the gym and the following three are especially beneficial. The first one gives you tons of bang for your buck in terms of versatility. The second two are effective at training certain movements that might be more difficult using free weights alone.

Cable machines use adjustable pulley and handle systems to provide tons of exercise options. They are hands down the most versatile machine in any gym. "I could easily use one cable machine for a full-body workout session," Kania says.

Here are just a few example of exercises that can be performed using a cable machine:

• Lat pulldowns
• Seated rows
• Single-arm rows and pulldowns
• Face pulls
• Biceps curls
• Triceps pressdowns
• Triceps extensions
• Pallof presses
• Squats
• Single-leg exercises like split squats and single-leg deadlifts

Both Roth and Farrell like to use cable machines for back exercises — especially seated rows and lat pulldowns — and to help their clients learn to effectively engage their muscles. Roth notes these exercises can be helpful for clients who are trying to achieve their first chin up.

The chest-supported row machine is another great machine, especially for building strength and muscle in your upper back. You sit on a chair with your chest pressed into a pad while pulling handles toward your body. Some chest-supported row machines use a horizontal pull while others use a slight vertical angle.

Many popular back exercises are limited by the core and leg strength of the trainee. For example, when performing a bent-over row with a barbell, your core and legs will fatigue faster than your back. Using a machine removes these limiting factors.

Now, you can effectively target your back without other muscle groups holding you back. This also makes the chest-supported row machine a good option for folks with back pain who cannot comfortably get into a hinge position for bent-over rows.

Your hamstrings have two major active functions. First, they assist your glutes in the extension of your hips, such as at the top of a deadlift. This function is best trained using free weight exercises such as Romanian deadlifts and hip thrusts.

The second function of your hamstrings is to flex your leg at the knee, bringing your feet back behind you toward your hips. It's harder to train this movement using free weights, and machines provide a perfect solution that allows you to increase load over time.

"I like to use leg curl machines for clients with underdeveloped hamstrings," Roth says.

There are two types of leg curl machines: lying and seated. The lying leg curl machine gives your hamstrings a bigger stretch, which can aid in muscle growth.

However, in my experience, many shorter trainees have a difficult time making this machine work for their bodies. If this is you, or if you are uncomfortable lying face down while you train, use the seated leg curl instead.

Despite their popularity and ubiquity in gyms, there is a lot of confusion about what exercise machines can and can't do. Here are three common misconceptions trainers regularly hear from their clients.

Many people believe that machines are safer than free weights, or that you won't get injured if you stick with machines and avoid the rest of the weight room.

The reality is much more complicated. Injuries and pain are very complex, and it's not possible to completely eliminate all risks while training.

"There's this belief out there that machines are a safer alternative to free weights. That's only the case if you have no idea how to perform a free-weight lift with good form," Tom Roth, CPT, a Chicago-based personal trainer and SFG-1 certified kettlebell instructor, tells LIVESTRONG.com. In fact, machines can be unsafe if you aren't sure how to use them properly.

Machines can be a great option for folks with limited mobility, such as those who are unable to comfortably get up and down off the floor or an exercise bench. They are also a staple of physical therapy and can be useful when returning to training after an injury.

However, for trainees without such limitations, using machines is not necessarily safer than training with free weights. Some machines may fit your body well, but others may lock you into a less efficient position that doesn't feel great on your joints.

Most machines are based on a standard height around 5'8" to 5'10", according to Michelle Kania, MS, CSCS, owner of One Day Better Training. "If you're much taller or shorter, the machine might not be suitable for your body," she says.

No matter how you choose to train, it's important to ask for help if you aren't sure how to perform an exercise or use a piece of equipment. Keep in mind it's normal to experience muscle fatigue while training, but you generally shouldn't push past pain or ignore pain in your joints.

Many people, especially those with physique goals, use machines because they believe it will help them lower body fat in the area they're training. This is known as spot reduction.

For example, if your goal is to slim down your arms, you might hop on the triceps extension or dip machines. Or, if your goal is to reduce body fat on your inner thighs, you might sit on the adductor machine.

However, spot reduction isn't actually possible, according to the American Council on Exercise (ACE). You cannot control where body fat comes off first — that is driven by biological and genetic factors.

Machines (or any other exercise) cannot lower your body fat in a specific place. Changing the appearance of your body occurs by building muscle and/or lowering your overall body fat by expending more calories than you consume.

Among the primary criticisms of machines is that they are a waste of time because they largely train muscles in isolation and don't mimic real-world movements.

Although both of these critiques are true, these limitations aren't always a bad thing in every case — especially in the context of a larger training program.

"One of the biggest machine misconceptions is that they're a waste of time because they aren't compound movements," Kania says. "Some body parts are best strengthened in isolation, and also machines can help give stability when people are new to movements."

Machines can be used effectively for building muscle. A body with more muscle has more potential for strength gains. Building and maintaining muscle mass is also critical as we age to preserve quality of life.

People shouldn't get so hung up on which machines are good and which are bad that they don't make it to the gym at all, according to Gabriella Farrell, CPT, a certified personal trainer at Stoked Athletics.

"While some exercise machines might not be the greatest bang for your buck, at the end of the day, it is effort which drives change," she tells LIVESTRONG.com. "A fear of making mistakes can become a barrier for people to get started at all. Making mistakes, learning from them and becoming better is all part of the process."