What Is a Smith Machine? Should You Use One?

Read the term ‘Smith machine’ and don’t really know what it is? Here’s what you know.

A Smith machine has a barbell connected to two vertical guide rods. The barbel can only move up and down and be latched to the rack at any height. This means no risk of getting pinned under the bar but also an unnatural movement pattern which is not optimal for form and injury risk.

Let’s get into the detail of what a smith machine does and if you should use one below.

What Is a Smith Machine?

A smith machine is an interesting combination of two types of gym machine. A barbell and a machine with a fixed path. The barbell is connected to two guide rods on both sides of the rack. That means the barbell only moves up and down but not forwards and backwards or from side to side.

In some cases the bar path is angled slightly or have a mechanism built in that allows the bar to move forward and backwards slightly. The barbell on a Smith machine is plate loaded and can be locked into place at almost every height through the bar path.

How much does a Smith machine cost? Find out here.

The smith machine is quite popular in many gyms because it allows people to lift more weight and do squats, bench presses and other popular barbell exercises with more safety. Or at least they feel safer. This might not actually be true in most cases.

People like Smith machines because they allow for more freedom than separate gym machines while also being able to lift heavier weights with the perception of safety because the barbell is fixed to guide rods that only allow up and down motion.

A Smith machine is a barbell that slides up and down on two rails. That means it can go up and down but not backward or forwards. There are a few high-end models that actually allow some back and forth movement because the vertical guide rods themselves are mounded on horizontal slide rails. Those are rare though.

Suggested: How tall is a smith machine and does it fit under my ceiling?

On most smith machines, there is a kind of safety catch system that allows you to hook the barbell onto by rotating it. So if you feel you can’t finish a lift you simply rotate the barbell and there always will be a safety catch within a few inches.

A Smith machine can be used for pretty much every exercise you can perform with a free barbell where the barbell moves straight up and down. Any exercise where the bar doesn’t follow a straight path can not be performed on a Smith machine.

However most barbell exercises that are commonly performed in the gym should have a pretty straight bar path and can therefore be performed on a Smith machine.

This includes exercises like:

  • Squat
  • Deadlift
  • Bench press
  • Shoulder press

So which equipment is a good alternative and common in a home gym? Keep reading to find out.

Problems With Smith Machines

I’m not a big fan of smith machines for the vast majority of exercises and think they offer the worst of two worlds. A smith machine can be loaded quite heavy since it uses the same weight plates as normal barbells. You might think the fact that the barbell is fixed on two rods makes it safer. And while it does in some ways, it is actually less safe than a regular barbell in other ways.

A Smith machine is safer because it’s almost impossible to fall over and get stuck under the barbell like it is with a free barbell. This is true and the biggest reason why people use Smith machines. They don’t like the risk of free weights but still want to do the barbell exercises. There is nothing wrong with wanting to be safer but sadly a Smith machine can be more dangerous in different ways.

Because the path of the bar is fixed, you can ‘cheat’ a little to lift the weight. Since the bar can only go up or down, you can use different muscles to push against the bar that would cause you to fall over with a free bar. This can create unnatural movement patterns and trains you to use muscles for certain movements that shouldn’t be used in that manner. So while you might get stronger in the Smith machine, it’s not very useful real world strength. For bodybuilding purposes where you just want to isolate a certain muscle AND you know very well how to target that specific muscle, a smith machine can work but even then in think there are better options.

Woman squatting in a smith machine

Suggested: Smith machine maintenance

Because a smith machine has a barbell, there are a lot of different exercises you can do. You have much more freedom to choose your body position and form than with other gym machines that have a seat. Those machines force you into a certain position to use them. This little bit of freedom on a Smith machine is actually quite dangerous. Because you can’t fall over, people often use terrible exercise form on Smith machines. Combine bad form with heavy weights and you’ve got a good recipe for injuries. A free barbell can of course be used with bad form as well but if your form is too far off with one of those, you’ll fall over or not be able to lift much weight so they are self-limiting in that way.

The fact that the barbell can’t move forwards and backwards on a Smith machine means you don’t have to stabilize the bar. While a movement is mainly done by a few of the big muscles, with a free barbell, you have to stabilize the bar at the same time as using the big muscles. Many small muscles around your joints have to work together to keep a free barbell stable. That work is taken out of the exercise by a Smith machine. So while the big muscles will get stronger, the surrounding support system isn’t being strengthened. This can cause weaknesses in the kinetic chain which means you can more easily hurt yourself when trying to lift something heavy in the real world.

Of course separate machines that target one muscle have many of the same issues. However, those machines are often designed in a way that forces you into a body position which leaves less room for injuries.

Smith machines cover up bad exercise form by limiting the movement of the barbell to only up and down. This can lead to increased injury risk and an incomplete development of musculature. This can limit real world benefits of the added strength and muscle.  


Hey, I'm Matt. Welcome to HomeGymResource.com. After working out in many different gyms for almost 20 years and helping people build their own home gyms, i've learned a few things i'd like to share with you.

Recent Posts