People frequently ask me about my thoughts on Smith Machines. Simply put, I think they should be called Jack machines because they do just that.
Smith machines were simply created as an excuse to avoid learning how to properly form for any functional exercise. They tote the benefit of providing a controlled movement for you, however they force your body into awkward movements that are not mechanically advantageous and only put you at risk for injury. Simply put, there is not a single benefit to a smith machine that can not be achieved through free weights or bodyweight exercises. Not only are they limited in their benefits, they also have a lot of disadvantages when compared to free weights:
- Smith machines set you up for injury. They force you into fixed, linear, unnatural movements, placing unnecessary strain on your joints. Your body is built to perform functional movements, such as pushes, pulls, and squats, in a 3 dimensional space. Forcing our joints to move in biomechanically disadvantageous positions can place excessive torque on your joints that wouldn’t normally occur if you performed the same exercise with a free weight or body weight. For example, a bench press on a smith machine will force your shoulders to flex and extend in a manner that strains your rotator cuff muscles; these positions would not occur in a properly performed barbell bench press or push up. Believe it or not, your body/weight does not move in a completely linear fashion when performing a free weight or body weight exercise. Next time you do a push up, look at your hand position relative to your body at the bottom and at the top of the movement. The position of your hand relative to your chest is different at these two parts in the movement.. That is because your body is developed to move in a manner that avoids excessive torque on our joints; in this case, your shoulders at the top of the movement and elbows at the bottom of the movement. The smith machine does not allow that freedom of movement, which only puts you at risk for hurting yourself.
- They stabilize the weight for you. While that does sound like a benefit, it is actually is detrimental to you. First, it eliminates a large benefit of exercising; being functionally fit. Weights are not stabilized in day to day life, so why train that way? Let your body learn how to balance a free weight and work against gravity. You also eliminate half of the stabilizing muscles that would be typically recruited when performing a free weight or body weight exercise. So now you’re just getting less bang for your buck.
- They resist gravity for you. The point of an exercise to place stress on a muscle and make it grow. Half of that stress comes from the eccentric motion in the exercise when you are lowering the weight. For example, you place stress on your muscle during a bench press by pushing the weight, but also by controlling the weight as you bring it down towards your chest. A smith machine controls that eccentric motion, so now you have eliminated half of the work on your muscles. Less stress on the muscle means less muscle growth, so why not just do the same exercise and get twice the value with less risk for injury?
Its understandable that some people continue to use them due to fear of free weights or difficulty with performing exercises without the guided movement. Fortunately, many of these problems also have easy fixes. For those who bench with a smith machine because they worry about the weight falling on them, you can simply ask someone to spot you. I promise you, most people will be happy to assist you with an exercise despite what you may think. If you just ask someone while they are taking a rest in between exercises, more often than not they will come spot you. If you are worried that you do not perform an exercise properly, then take a video of yourself performing the exercise. Compare it with how-to tutorials on YouTube or some of the guides on this website. If you aren’t doing them correctly, then you have a reason to get better at them, not a reason to stop doing them. A proper squat, for example, is an important functional movement that everyone should know how to do. If you aren’t doing them properly, learn how to do them correctly. Don’t make it worse by getting into the habit of doing smith machine squats, which require a movement that isn’t even possible without the support or stabilization from a smith machine. If you only have smith machines and no barbells (i.e. Planet Fitness), use dumbbells, do bodyweight exercises, or get a new gym. You are investing in your fitness and don’t let that time and money go to waste.
Again, a smith machine is simply an excuse to do exercises with poor form. They limit the benefit of the exercises you are performing and put you at risk for injury. If you want to get the most out of your workouts, drop the smith machine and pick up the free weights or do bodyweight exercises.