“There is simply no other exercise, and certainly no machine, that produces the level of 
central nervous system activity, improved balance, skeletal loading and bone density enhancement, muscular stimulation and growth, connective tissue stress and strength, psychological demand and toughness, and overall systemic conditioning than the correctly performed full squat,” said Mark Rippetoe, author of Starting Strength.
THE GENERAL POPULATION NEEDS STRENGTH TRAINING
As a strength trainer, I often meet with skepticism regarding the general population’s ability and to perform barbell movements. I battle the stereotype that as a competitive powerlifter, I will train all my clients like powerlifters. I witness a misconception that I will design my clients’ workouts to create a robust, even rotund, powerlifting body.
In fact, every single one of my clients will learn to lift with barbells at some point in their journey. I do not expect them to become powerlifters, but barbells are the single greatest tool for training. Not only does science provide evidence of this, but I have personally witnessed these benefits in my clients, including my dad who was diagnosed with Huntington’s Disease in 2014.
WEIGHT LIFTING MACHINES ARE INFERIOR TO FREE WEIGHTS
Historically, free weights and barbells were the primary avenue for lifting. In 1986, however, the reversal of this system of lifting began. The rise of the Nautilus Machines and corporate gyms, began when Arthur Jones designed the first circuit style machines.
For gym members looking to get in shape and spend less money on personal trainers, this was a dream come true. Additionally, gym owners were happy with their savings and earnings simultaneously increasing. The machines appeared to be a winning invention. Unfortunately, these gains were short-sighted as far as the benefit to gym-goers. On the surface everyone seemed to benefit, the missing link was the physical, and even mental, benefit of true strength training.
JOINT HEALTH
According to Rippetoe, “the body functions as a complete system – it works that way and it likes to be trained that way.”
Yet machines were designed to isolate just one unit of the body, or one muscle, at a time. This method of training is harder on the joints as they move in a singular plane of motion, repetitively and independently. Barbells, on the other hand, allow weight to be moved in the way the body is designed to move it.
A primary example of the poor movement patterns forced upon the body by machines is the Smith Machine. This machine, along with many others, forces the body to move the way the machine moves. Yet humans are not each born with the same proportions (or leverages), our bodies were not designed to squat or bench in one designated plane of motion.
BALANCE AND NEUROLOGICAL STIMULATION
Machines do not allow for adaption to surroundings, a.k.a. proprioceptive awareness.
My dad who has Huntington’s Disease has benefited greatly from performing strength training twice a week.
They do not force the body to recruit its ability to control and stabilize weight. In contrast, barbells produce what Rippetoe refers to as a proprioceptively rich environment:
An unstable (yet controllable) physical situation in which exercises are performed that cause the body to use its internal balance and stabilization mechanisms (which is not present in machines).
Since muscles function simultaneously in the rest of life, this should be reinforced in one’s training. Not only do barbell movements teach the body how to move correctly, they force the body to adapt in ways that benefit its internal functions.
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