Machines Still Build Muscles

Don’t overlook the muscle-building benefits of fixed-resistance machines.

In an industry that is all about three-dimensional, “functional” movement aimed at achieving maximum crossover to movement quality and performance, have we actually forgotten that fixed-resistance machines still have some value?

This isn’t another fixed machines versus free weights article. That’s pretty much been done to death. This article purely aims to re-ignite your passion for using fixed-form machines for one very specific goal: building muscle.

Machines are unmatched in isolating muscles. [Photo credit: Shutterstock]

Our industry tends to be very black and white, and frequently seeks answers in absolutes. I am often confronted with arguments from personal trainers and sport science students that you should never use a fixed pattern of movement, and instead should devote all of your training to free-loaded movement.

That for me is the problem, because resistance machines have value. To avoid them is a just a reflection of the current dogmatic trend in the industry. I do not intend to justify fixed machines for increasing your strength or your vertical jump – it’s not about that. It is for those that want to unashamedly look more muscular but couldn’t really give a damn about strength, power or performance. It’s about aesthetics in its truest from.

If you want to add muscle for aesthetics, you should include fixed machines in your program.

What do I mean by fixed machines?

Although it may seem like an obvious one, I think it is worth spending a short amount of time quantifying what a “fixed-form resistance machine” is.

For the purpose of this article, I’m referring to either plate-loaded or selectorized (controlled by pulleys and levers) machines. Any machine with a fixed pattern of movement that can’t be altered, no matter what angle you pull or push from, is “fixed form.”

Some consider cable machines to also be “fixed.” I presume this is only because they are fixed to the floor. They do not enforce fixed-movement patterns; they provide the user with multi-planar, unrestricted movement and therefore should be classed as free weights (or at least toward that end of the continuum anyway).

Why You Should Use Fixed Machines for Muscle Growth

Fixed machines provide a stimulus for growth.

The process by which your muscles grow is called hypertrophy. In essence, the muscle-building process occurs in response to either the degree of loading – otherwise referred to as mechanical tension, or the metabolic demands placed upon the muscle.1 When you challenge a muscle with either of these stimuli you create overload, and thus create growth.

For that reason it has been proposed that it is not so much how the load is placed on the muscle, as long as it is sufficient enough to stimulate the muscle to adapt. 2, 3, 4

Your body can’t tell whether you are lifting a dumbbell, barbell, or lifting through a fixed pattern – it just reacts based on the demands placed upon it. Whilst free weights often provide greater increases in strength, they often provide very similar body composition changes.5 Stimulus is key.

Fixed machines decrease assisting muscle “noise.”

Free weights are without question superior for activating stabilizing muscles, there’s no denying that. For example, a study comparing free weight and fixed bench press 6 found that the free weight press stimulated the deltoids and trunk musculature much more than the fixed pattern machines did. Similar results have been found with the lower body muscles during leg press and squat movements as well.

In a way though, that works in your favour if you wish to reduce the “noise” of these other muscles. Fixed machines can isolate a muscle much better than a bar or dumbbell, providing a more thorough, targeted structural stimulus.

This is important if you feel you need to “work up” a lagging muscle whilst avoiding the activation of a stabilizing muscle due to overdevelopment, soreness, or injury.

Fixed machines can create tension through a full strength curve.

With the advancement of biomechanics technology, fixed-form training machines have significantly evolved in design. They are now better suited to perform muscle building than ever before. Depending on their mechanical design, the fixed-form machine offers external torque patterns that can challenge a muscle throughout its full range of motion, not just relying on gravity for resistance. 7, 8

Fixed machines often create such tension due to the arrangement of cams and variable resistance. This provides a challenge to muscle fibers at different angles to free weights, and allows the muscle to work fully through a greater range of motion. This in turn helps to create the overload necessary to promote muscle mass.

Increased stability can mean increased force output

Increased force output is important for stimulating the activation, and then overload, of muscle fibers. Research has shown that heavy loads may hold “superiority” for muscle building 9 – although that is not to say that lighter loads cannot promote muscle growth too.

However where balance is required, as with coordinating the path of a dumbbell for example, force output may decrease. A study by Schwanbeck et al. 10 found that the 8 rep max for a fixed machine squat was 14-23kg heavier than for a free-weight alternative.

Similar results have been found in other studies, where the lack of stability from free weights caused decreased training loads. 11, 12

Ultimately, you don’t need to worry about controlling a safe bar path with a fixed machine, it is does it all for you – that’s why you don’t get “leakage” to other muscles. It’s direct. And that’s not a bad thing.

The Final Consideration

Both fixed-form machines and free weights should be used to maximize muscle growth. The current nature of the industry is to shun machines, and it a bias that causes people to miss out on potential for muscle building variation. Free weights provide a stimulus to stabilizing muscles, whereas fixed machines reduce stabilizing muscles’ noise and allow isolated muscles to be more effectively targeted and overloaded.

But not all fixed machines will suit you. It’s a matter of personal preference. Some might restrict your range of movement, or place excess stress on a limb. Or you might just not like the activation it gives you around the joint moment.

If this is the case then you need to avoid it and find an alternative. Once you’ve found a machine that suits your needs, it’s well worth including. Unless you try them, you’ll never know. So consider moving away from the free weight area just once, and open up your muscle-building potential.

Find out more advantages of machine training:

Don’t Dismiss Machines for Athletic Strength


1. Scheonfeld, BJ, “The mechanisms of muscle hypertrophy and their application to resistance training“. J Strength Cond Res. 2010; 24(10): 2857-2972.

2. McBride, JM, Hot topics: machines versus free weights“. [Online PDF]. NSCA-Lift, org.

3. Pipes, TV, “Variable resistance versus constant resistance strength training in adult males“. Eur J Appl Physiol Occup Physiol. 1978; 39(1): 27-35.

4. Maddalozzo, C et al, “High intensity resistance training: effects on bone in older men and women”, Calcified Tissue International. 2000; 66: 399-404.

5. Boyer, BT., “A comparison of the effects of three strength training programs on women“. J Strength Cond Res. 1990; 4(3).

6. McCaw, ST & Friday, JJ. “A comparison of muscle activity between a free weight and machine bench press“. J Str Cond Res. 1994; 8(4): 259-264.

7. Haff, G., “Roundtable Discussion: Machines Versus Free Weights”. National Strength & Conditioning Association. 2000; 22(6): 18–30.

8. Tous-Fajardo, J et al., “The flywheel leg-curl machine: offering eccentric overload for hamstring development. Int J Sports Physiol Perf. 2006; 1: 293-298.

9. Schoenfeld, BJ., “Muscular adaptations in low- versus high-load resistance training: a meta analysis“. Eur J Sport Sci. 2016; 16(1): 1-10.

10. Schwanbeck, S et al., “A comparison of free weight squat to Smith machine squat using electromyography“. J Strength Cond Res. 2009; 9: 2588-91.

11. Kohler, JM et al. “Muscle activation patterns while lifting stable and unstable loads on stable and unstable surfaces“. J Strength Cond Res. 2010; 24(2):313-21.

12. Cotterman, ML et al., “Comparison of muscle force production using the smith machine and free weights for bench press and squat exercises”. J Str. Cond. Res. 2005; 19(1): 169-176.

Be the smartest person in your gym

Everything you need to know about strength in in your inbox.