Machines for Building Muscle: Game-Changer or Waste of Time?

Are machines worth programming for your clients? If building muscle and getting stronger are some of their goals, then the answer to this question might surprise you.

If you’ve been following trends for the past decade and longer, one thing you’ll have witnessed is that the discourse around this topic swings between extremes – first, machines are useless and dangerous, and free weights are the only effective way to train; then, machines are incredibly effective and will pack on muscle like nothing else.

After all, why perform a seated chest press when you can simply opt for a dumbbell press?
Why perform a leg press when you can just squat?

If you’ve ever wondered about this, especially when deciding on what exercises and elements to include in your clients programs and periodization models, my goal is to give you a better mental framework for understanding this topic, so you can think critically and apply it effectively.

First, let’s establish an important point:

Not All Machines Are Created Equal

There are certain movement patterns that are difficult to replicate without the use of machines. A perfect example of this would be knee flexion, with the use of a standard leg curl machine.

There ARE other alternatives, for example, you can perform knee flexion with a swiss ball, however, as we discussed in this article, the difficulty lies in applying progressive overload to that specific exercise.

To put it simply, leg curl machines are far more effective than other variations and are practically superior in almost every way.

As another example, we can look at the seated calf raise exercise. You can complete this movement by adding weights over your thighs, but nothing will trump the seated calf raise machine for ease of use and comfort.

We can think of some other examples such as hip adduction and hip abduction, which are possible to complete without the machine variations, however are significantly more awkward to perform and progressively overload. 

The leg extension is another excellent machine due to its ability to specifically target the rectus femoris, a muscle that is difficult to challenge with any free-weight quad-based exercise.

That being said, I want to hone in on exactly the type of machines I mean to refer to when discussing this topic, which would be those that have similar free-weight variations.

For example:

• Barbell squat versus hack squat machine/pendulum squat/leg press
• Dumbbell press versus chest press machines
• Free-weight or cable rows versus machine rows
• Many isolation-type machines versus their free-weight counterparts

Are the free-weight versions of these movements always superior to their machine-based counterparts, especially in the realm of muscle-building?

The answer is a resounding NO.

Let’s look at exactly why this is the case by breaking it down into several supporting points.

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Reason #1 Prioritizing Client Safety

One of the most obvious reasons as to why machine-based movements can be superior is their relative safety compared to using free-weights, with the assumption that the machine is being used appropriately.

Typically speaking, machines are built in a way that if the user experiences any catastrophic failure, there are measures in place to protect them from any serious harm. 

Many lifters are also apprehensive about training the big 3 (squats, deadlifts, and bench press) close to failure because failing on these lifts can mean injury or embarrassment.

If you have any clients that see you once or twice per week, and train some days on their own, then it is of utmost importance that you select exercises that they feel safe executing alone.

Below is an example of pushing a seated machine press to concentric failure, and simply pressing the foot-stool to help me lower the machine limbs safely. If I chose to fail on a dumbbell press or a bench press, this would be made significantly more difficult to execute safely.

This isn’t to say that you can never program in free-weight exercises such as squats, deadlifts, or bench press, only that they require a client with more experience and awareness.

What I am trying to avoid is to make absolute statements such as “Machines are ALWAYS superior to free-weights”, which is not a belief I hold, nor one I want to express.

The secret lies in understanding context and knowing when and where to use either option.

Reason #2 MORE CONSISTENT STRENGTH CURVE

The second reason why machines may be a superior choice compared to free-weights is the more consistent strength curve.

The strength curve of a movement refers to how resistance and muscular effort change throughout the range of motion—determining which parts of the lift feel harder or easier based on mechanical leverage and muscle activation. We cover this in more detail in our article on muscle tension.

For example, in a barbell squat, the most challenging part of the lift is typically the bottom position (the sticking point), where mechanical disadvantage and muscle length create the most resistance. Once a lifter passes this point, momentum and improved leverage make it significantly easier to complete the rep.

The problem here is that the weight selected has to be limited to what you can lift through the hardest part of the movement—even if the rest of the range of motion could handle more load.

This means that stronger portions of the lift remain underloaded, reducing overall muscle stimulation and growth potential.

If instead, we look at machine-based squat movements, we’ll realize that they are built with this in mind and are therefore designed to provide a more consistent resistance curve, challenging the user throughout the entire range of motion.

Take the pendulum squat for example, which deloads the bottom position of the movement, ensuring that the totality of the rep remains difficult.

Another example is the reverse-band hack squat, where the bands reduce resistance in the bottom position, aligning the strength curve with the lifter’s natural strength profile.

This setup allows for heavier loading at the top, where the lifter is strongest, while minimizing excessive strain at the bottom—maximizing muscle tension throughout the entire range of motion without unnecessary joint stress.

If we shift our focus to isolation exercises like lateral raises, the strength curve disparity becomes even more obvious.

With dumbbells, the first 10-15 degrees of shoulder abduction experience almost no tension, while the top 70-100 degrees become disproportionately challenging due to the effects of gravity and lever length.

In contrast, a machine lateral raise provides consistent tension throughout the entire range of motion, including the bottom portion, where dumbbells fall short.

Again, this isn’t to say dumbbell lateral raises are obsolete and should be avoided entirely. Simply that varying exercise selection between free weights and machines can optimize muscle stimulation, provide new adaptation stimuli, and enhance overall progress for your clients.

One way certain machines modify the strength curve of an exercise is through the use of a cam.

A cam is an asymmetrically shaped wheel, often resembling an egg or teardrop, that alters resistance throughout the movement. As the exercise is performed, the belt or cable wrapped around the cam moves along its contour, changing the leverage and adjusting the difficulty at different points in the range of motion.

Although not all machines integrate cams, those that do are designed to better match the muscle’s natural strength curve, ensuring more consistent tension and a more effective workout.

Here is a visual example of how they work and how the forces change depending on the position of the belt over the cam.

Reason #3 Limit Fatigue, Maximize Growth

The final point I want to highlight about why machines can be an excellent addition to a workout program is their reduced coordination demands—which might initially sound like a downside, but in the right context, it’s actually a major advantage.

Let’s take a look at the Smith machine squat below. (You’ll also notice that I’ve attached bands to modify the strength curve, aligning resistance with the typical strength profile of this lift.)

The Smith machine removes the need for barbell stabilization, allowing me to focus purely on exerting maximal force through the target muscles.

The benefit is clear—by reducing coordination demands, I can train closer to true concentric failure without my stabilizers or nervous system fatiguing prematurely. This means more direct muscle stimulus, less systemic fatigue, and potentially greater hypertrophy gains.

This ties into the concept of ‘stimulus-to-fatigue ratio’ (SFR), popularized by Dr. Mike Israetel, which compares the amount of fatigue a lift generates to the hypertrophic stimulus it provides.

As an extreme example, deadlifts performed to failure would generate massive fatigue while providing only a modest hypertrophic stimulus, giving it a very low SFR score. The sheer recovery cost far outweighs the muscle-building benefits, making deadlifts to failure a highly inefficient strategy for hypertrophy.

Training to failure naturally generates more fatigue, but we can minimize systemic fatigue by selecting exercises that offer a high SFR—such as machine variations. This allows us to maximize hypertrophic stimulus while keeping fatigue manageable and recovery efficient.

As a side note, something I remember “learning” early in my career was the idea that machines have little to no carryover to free-weight movements.

I believed it—blindly—because “it made sense.”

Well, imagine my surprise when, after months without directly barbell squatting, I decided to test my strength… and cranked out 275 lbs for an easy set of 8.

Nothing groundbreaking, and certainly not my all-time best, but considering that strength hasn’t even been my focus this past year, it was eye-opening.

That experience alone shattered the myth that machines don’t carry over to free weights.

There you have it, no more free weight exercises!

Not so fast! This article isn’t meant to steer you away from free weights. In fact, speaking from experience, the majority of my own training is free-weight based. However, I incorporate machine variations strategically when I want to isolate a specific muscle, manage fatigue, or optimize resistance through the entire range of motion—all while keeping everything discussed here in mind.

That said, not all machines are built for everyone. Many commercial designs cater to an ‘average’ height range, making them awkward for lifters who are particularly tall or short. 

That’s why it’s necessary to select machines that properly fit your client, ensuring effective muscle targeting while minimizing unnecessary joint stress.

Next time someone tells you machines are useless, you’ll have the knowledge to set the record straight—because, like most things in training, the real answer is context-dependent.