Why Slouching Is Bad
When I was little I got some cues from adults that slouching is bad and that I should try to maintain good posture. Until recently, I never really took their advice to heart. I do not recall anyone explaining to me why I should not slouch and at some point, no one reminded me about slouching anymore during class or at home in front of the computer. I will try make a case for why it is bad.
Even though I have internalized this case, I still have not conquered my slouching habits. When I am focusing and using a computer, my posture suffers greatly. But, by being mindful of my posture, I think I am steadily increasing the percentage of time that I am not in a terrible position.
I see you shifting in your chair as you read this. Get comfy and balanced as we build our case against slouching.
When you slouch you support your body through your spine and the discs in your spine. It is like you are hanging your body off of your spine. With good posture, your body weight is supported through your muscles that wrap around your body. Your muscles are much better at taking load and abuse of the weight of your body than your vertebra and discs. Your muscles heal more quickly and respond to stresses by getting stronger. Your bones and discs are not good at responding to stresses and eventually can be worn down from repeated stresses. When slouching, people tend to have the head far out of alignment from where it would be in a neutral postural position. The more out of alignment it is the more force your body (probably your spine if you are slouching) needs to generate to keep you from falling over.
I think that the sudden rib pain I was feeling in my left ribcage was because I was crushing the little muscles that are between the ribs. Since I started slouching less and building up the muscles that support this region, I have not had any shooting or sudden pain in my ribs.
Slouching also reduces the size of your lung cavity. Some of the muscles that are responsible for posture are also responsible for breathing. If you maintain a good posture, these muscles will be stronger and more capable in helping you breathe. If you slouch for most of the day, you might even find these postural breathing muscles have atrophied to the point where they can barely be activated. The muscles that move when you breathe while slouching will have to work harder. You also probably will not get the full range of motion of your diaphragm. You will not be getting good "deep" breaths that fill your lungs.
Lastly, by slouching or resting your body on the back of a chair, you are depriving yourself of balancing practice. When you use your postural muscles, they have to maintain your balance so you do not move or fall. This might not seem like much, but having good balance and proprioception is important for all the movements you make with your body. Good sense of body position will make you more likely to assume a good position while performing an activity that you have not developed your skill at. Overall, the better your balance and postural muscles are the less likely you will put yourself into a compromising position and get yourself hurt.
Well there it is, the case for why we should not slouch. It is a noble goal, but also a hard to achieve one. Be mindful of your position and you will improve your posture over time. Choose to go down the path toward improved posture one step at a time. We have years of bad habits to break down, but thankfully we all have plenty of time to do it!