How Vision Affects Posture and Movement

Imagine that when you look upon the world, the ground seems to be sloping away from you. Subconsciously, your brain perceives, through your visual sense, that you are always going downhill. This is an optical distortion. And this is how I see the world. 

How do you think your body reacts and positions itself against this impending downward slide?

Think about how you hold yourself when you are hiking down a steep slope. In order to maintain upright balance and overcome gravity, you pull backwards into the hill behind you. Posturally, you extend your upper body and torso back, away from the sloping incline. When this happens, your shoulders move behind your hips. Also, your chest lifts; your ribs flare up and out; and your lower back arches. All of this odd contortion causes the surrounding muscles to tighten.

If this description conjures up images of back pain and poor breathing, you’ve got the idea. Since my brain thinks I am about to tumble down a hill at each and every instant, this is my posture! To protect me from falling, my body extends backwards--all the time. This protective mechanism--body extension--also makes me hurt and move inefficiently. My inability to walk properly is a good example.

Walking requires alternating between heel strike, single leg balance (mid-stance), and push off on the left and right sides. In order to take a step forward, you lift one leg and swing it forward while balancing on the other leg. And, in order to do this correctly, you must be able to reference the ground through your heel while centering your body weight on the opposite leg.

Since I am a former gymnast who was always on her toes, and since I'm also under the optical distortion that I am going downhill, I don’t use my heels when I walk. To explain, think about this. Where is the pressure in your feet when you walk down a slope? The front of the foot, right? Well, that is how I walk all the time. My heels barely contact the floor. I am light and floating over the earth just like I did when I was a gymnast many years ago. Consequently, I can’t center myself appropriately over my leg in mid-stance and can’t “push off” correctly.

One of the Postural Restoration Institute (PRI) exercises I have been given to improve my gait is to mimic someone walking. The photo to the left was taken at the training course I recently attended. Here, one of the course instructors and institute founder, Ron Hruska, MPA, PT, is trying to mimic my faulty gait. I had initially tried to follow him but failed miserably, so we switched. Notice how unbalanced he looks when he tries to mimic me (with my poor mechanics and optical distortion!). His body doesn’t even know how to start moving correctly.

 Here’s what’s happening: The body works as a kinetic chain that is initiated upon heel strike when walking. Since I lack this initial phase of gait, the normal chain of muscle activation needed to move me forward in space doesn’t happen correctly. My hip external rotators (glutes) and leg adductors (inner thigh) should activate when I walk but can’t because they don’t have a reference through my heel. Without the proper muscles firing, I can’t center on one side at a time. So, I compensate and walk forward by pulling myself into the space before me with my hip flexors and neck.

Successful heel strike is achieved through your peripheral vision. Awareness of the periphery guides your movements. Peripheral vision helps you to orient yourself in space. Unfortunately, for many of us, our peripheral vision shuts down, particularly on the left side. Our brains are double-wired to notice our surroundings on the right but only have one pathway to process visual information from the left side.

When I went to Nebraska last spring and had my vision tested at the PRI Vision Center I was told my left eye tended to “drop off.” It just stopped working. 

The fact that my left eye doesn’t process correctly creates this optical distortion I’d referred to earlier: going down a hill while on flat land. This, in turn, generates a perceptual distortion in how I walk. I stay on the front of my feet and cannot perceive the ground through my heels. Additionally, I lose my left periphery and don’t know where I am in relation to my surroundings. Thus, I cannot move forward without cheating. I am literally lost in space! 

 The cool blue specs I modeled last month are helping me find the ground. Specifically, the glasses change how my brain perceives my environment: The glasses alter my visual inputs so that my brain now perceives flat ground as flat not sloped downward. With this new perception of the world, I can stop extending backwards to steady myself. This reduces my pain and changes my dysfunctional movement patterns, allowing me to find my heel. Hurrah!

The exercises I do with my glasses on help me find my left periphery and center my weight on a single leg at mid-stance though correct muscle activation. I’m still learning to breathe, walk and use my visual sense!

Vision tips to improve your posture and gait
You don’t need fancy glasses to benefit from visual training. Just try the suggestions below.

Look up when you walk. 
Many of us gain stability in our body by focusing on the ground. In some cases the eyes are our only source of stability, the only thing holding us up. This leads to compensatory gait mechanics where the eyes are pulling us through space. Consistently staring down, we move forward by looking from one point to the next point, pulling ourselves along, instead of using proper body mechanics from the hips, pelvis and legs. Watch people walk. You’ll be amazed at how many people gaze intently at the floor. I was!

Notice your left side by using your peripheral vision.
 You use your peripheral vision to sense movement and to judge distance, not to actually “see” things. Don’t expect to see objects clearly in your periphery. Being aware of an object's presence and having an idea about your physical relationship to it is enough. Here are three techniques to help you notice your left periphery.

Technique One: Last month I introduced a grounding exercise which is easily modified into a vision exercise by gazing to the left. Keep your head centered and only shift your eyes left. Hold the position with the altered gaze for 30 seconds while focusing on deep diaphragm breathing.

Two: When walking, pick out a stationary object in front of you--on your left side--and observe yourself moving past it.

Three: See your left hand swing in front of you as you walk forward while keeping your gaze straight ahead with eyes on the horizon.

Vision is the dominant sense in your brain and has a strong influence on posture and movement. Untreated vision issues may be impeding your healing. Many good therapeutic approaches will fail if vision issues are standing in the way of progress and not addressed. This article has given you a brief introduction to a few concepts about vision, posture and movement. If you have more questions, please leave a comment below or contact me directly.

Reference: Postural-Vision Integration Course