How Gym Mirrors Make You Weaker and How to Hack the Visual System for Faster Progress

“Why don’t you have any mirrors in Blacksmith?” – Great question. Is it that we just can’t afford them and are waging war on gym selfies? It actually has nothing to do with cost or vanity, but the simple fact that looking in a mirror while training makes you significantly worse at the task you are performing. Read on to see why gym mirrors are actually the devil, and how the simple act of facing away can make a significant improvement in your lifts

Lifting with your brain, attention pools, the visual system, and the power of proprioception

The first myth that needs to be dispelled is that you lift weights with your muscles. Sure they actually provide the force to overcome the inertia, but muscles are actually pretty dumb tissue, they’ll respond to pretty much any electrical impulse, like a electrostim machine, a taser, or sticking a fork into an electrical socket. However, we’re going to assume you’re not hooking yourself up to your car battery every time you want to move the couch, so in everyday life the “battery” creating the electrical impulses that command your muscles to contract is actually your brain. Without the brain and spinal cord sending small electrical impulses to the muscles at all times you are literally reduced to a glorified immobile puddle of flesh that is being held together by your ligaments and bones.

Ok so the brain is pretty important; however you may have heard it doesn’t multi-task very well. Which is partially true. I don’t want to get too much into multi vs central attention pools and their effects on motor performance, but one thing we can agree on is that the more complex the task, and the more options we have, the less likely it is that we will be able to do anything else at the same time with any shred of competence. For example, If I take you out to the driving range and ask you hit a few balls, whether or not you suck to begin with, you will suck way more if you’re asked to recite the alphabet backwards while setting up and taking your shots, or you will slow significantly in your reciting while you hit the ball, but without fail, you will suck more at one of the tasks than if you were to do them separately. Now what the hell does this have to do with squatting in a mirror?

Vision is extremely complex; not only does visual information come in upside down, but it must be broken down and then reconstructed before it is interpreted and the brain makes its best guess as to what’s out there. How complex is the system? The process is so specific that some neurons respond to lines that are exactly 45 degrees, but not to ones that are 44 or 46 degrees. So needless to say your vision is taking a lot of cognitive energy (about 30% of the cortex is dedicated to this task vs 8% for touch and 3% for hearing), and when you look in the mirror you’re inverting the image again, and you’ve made the process of orienting yourself to your environment even harder for your brain. Consequently, you must focus more of your attention on processing visual information and less on the task of coordinating those millions of electrical impulses that are controlling the muscles involved in your squat. Just like when you were 10 and playing with your remote control car, when the battery dies the car gets slower and reacts poorly; your muscles are no different. So by simply looking in the mirror to improve your form, you’ve actually made yourself worse at the task, and made yourself slower and weaker. You’re also taking away some of the attention from a very powerful system of motor coordination: the proprioceptive system.

Unlike the visual system that focuses on the external environment and how you relate to it, the proprioceptive system is an internal system that communicates positions of joints in relation to each other and muscular tension differentials, and it just so happens to be way faster and more accurate than the visual system for coordinating movement. The problem is that our brains are hard wired to accept visual information as more important and more accurate; however, if you just turn around and face away from the mirror, you never give your brain the chance to override proprioceptive input with doubly-inverted visual information,  and you’ll instantly starting moving better. A common phenomenon that occurs when you turn someone around and face away from the mirror is that previously painful movements are suddenly pain free; this occurs by correcting small, visually imperceptible, movement errors that cause tissue to be overloaded.

Taking it a Step Further – Hacking the Proprioceptive and Visual Systems to Learn and Improve Simple/Essential Movements

note: we mainly use these methods for people who have a really hard time acquiring a basic skill, feeling an important sensation, or for those who are coming back from an injury that would have affected their feedback mechanisms – most people will do just fine looking away from the mirror and acquiring the skill with their eyes open

The relationship between vision and the inner ear, how less than 1% of your vision takes 50% of the brain’s visual processing power, and how an exercise fits on the stability continuum changes the need for focal vision

Try this:

1. Take your squat position, and put your arms straight out in front of you (think old school zombie movie or frankenstein)
2. Close your eyes
3. Squat to the bottom and hold for a 3-4 seconds
4. Return to the start
5. Bonus points if you can have someone film you eyes open vs eyes closed
6. Repeat the experiment with one leg in front of the other and do a split squat
7. Repeat the experiment by taking one leg off the ground and doing a single leg deadlift

Chances are that if you are a decent squatter that you accomplished the bodyweight squat with little difficulty, and with the eyes closed, it was smooth and you may have noticed some sensations you don’t normally notice (glute stretch in the bottom, the thighs pressed against the torso, tension in your knee etc). If you filmed the two attempts, there’s a good chance that the eyes closed version looks smoother and more controlled than the eyes open one. Chances are the split squat with your eyes closed was harder, but you probably still did it. If you weren’t able to do the first two, then your proprioceptive system needs some work, but fear not, there’s instructions on how to improve below. Now for the one legged deadlift; if you did it, congratulations, you have a very efficient proprioceptive system, but even if you did, it was probably pretty damn difficult and may have taken you a couple of tries.

So closing the eyes often improves the bodyweight squat or at the very least brings awareness to sensations you usually ignore, but closing the eyes made the split squat and one legged deadlift worse. In all three of the exercises we closed the eyes to increase the neural output and attention we are paying to the proprioceptive system and took away the visual system’s scanning of the external environment, so what was the main difference between the three exercises? The biggest difference was the stability demands of the exercise; with each progression the exercise selection became more unstable.

Low stability demand exercises, think two feet on the ground or torso supported, centre of gravity (the weight being used) is at or below the hips, and moving in one plane (not twisting or rotating in multiple directions) i.e. deadlift variations, bench press variations, T-bar rows, barbell hip thrusts etc. rely more on your strength than on your ability to balance. These types of exercises can benefit from eyes closed or or fully blindfolded methods by taking the attention normally spent on the visual system and allowing you to focus it entirely on the internal cues arising from your proprioceptive system. This can increase the control you have over that motor pattern, leading to more efficient patterns of muscle recruitment, and better movement quality while learning or relearning an exercise.

Somewhere in the middle of the continuum lies exercises like barbell loaded squats (these are different than our bodyweight example because the centre of gravity is higher), split squats, lunge variations, and other exercises where you actually move through space or rotate like barbell twists. These exercises have a high strength and high stability demand, and therefore completely closing the eyes doesn’t usually improve performance or the rate of skill/form acquisition, this is due to the relationship between the horizon and the inner ear.

You may have had a bad cold or ear infection and felt incredibly dizzy or had mild vertigo; this happens from changing or closing off the input from the inner ear. When the information from the inner ear and the visual system don’t agree, this causes huge problems for you and the resulting confusion usually leads to dizziness, nausea and generally a terrible day. The inner ear and visual system work together and check each other to help you make a decision on where you relate to the pull of gravity and the horizon. So as the stability demands of an exercise increase, so does the need for the visual system, so does this mean we need to take all that valuable attention away from our proprioceptive system and neural drive to the muscles? No, we can use a portion of the visual field instead.

Less than 1% of our visual field takes up 50% or more of our brain’s visual processing power. It’s the 2-3 millimetres right in the center of our visual field and it’s responsible for all the fine detail we see. Try it out, focus on the “O” in this random assortment of letters STKZVZVCFFTRFOGHTSCVGDTVVS now try to read the rest of the letters without changing your focus from the centre of the “O”. The thing is, for exercises in the middle of the continuum, we don’t need this type of focus, we just need a general sense of where we relate to the pull of gravity, and most of that information comes from the very bottom of our peripheral vision. This is where the partial blindfolded method comes in. If you tie a blindfold so that it comes just below the bridge of your nose, the relationship between the inner ear and the visual system is maintained, and your balance improves drastically; however, you still take advantage of the higher output to the proprioceptive system and higher neural drive to the muscles by blocking the most neurally intensive portion of your visual field. Meaning all the good things mentioned above, smoother motion, better movement quality and skill acquisition still apply.

How about high stability demand exercises? Ones in this category include high velocity movements, especially overhead, or exercises where your head and or body will be moving through space in large degrees. Examples would be the olympic movements and their variations, any kind of jumping or plyometrics, or anything involving catching an implement. For these types of exercises you react not only to gravity, but also to another objects, or are required to manage other significant multi-planar forces; this is what vision is designed for and you need to use it in it’s entirety. That being said, many of these movements can be broken down into components that would fit into the medium to low stability demand area of the continuum, and improved. Once those improved pieces are reintegrated into the whole movement, the whole movement usually improves by better sequencing, improved strength, and hitting key positions in the movement. For example, a kick in soccer could be reduced to the lower leg swing, it could be made more efficient, strengthened, and increased in power, then when the athlete integrates that motion into the full kick with lead up, an increase in shot velocity and accuracy occurs.