[What is a good posture for practicing?] Things Guitarists should know about their body

Hello!
I'm Fujioka Takuto, guitarist in an acoustic band called BABY BABY, and occupational therapist.
Thank you for reading as always!

The theme of this time is "What is a good posture for practicing?" There was an article that I wrote about posture before, but since it was a general explanation, I'm going to focus on and consider the posture when playing the guitar again!

(*"Good posture" here means, a posture in which you're comfortable and balance is stable.)

Let's get going!
This time, we'll look at the posture while sitting in a chair, the "sitting posture".

Let's check what kind of posture you usually have when you practice guitar sitting in front of your PC!
My sitting posture during practice looks like this.

The height of the chair is set so that my feet are firmly on the floor with a footrest.
I'm conscious of the front part of my body, trying not to look down as much as possible.

The green line in the photo is the center of gravity line, and the yellow triangle is the pelvis.

(The center of gravity was mentioned in the article in the past, "Balance Edition", so if you haven't yet, please read that first!)

The white line is the spine, and the green circles are the "balance points", from above the AO joints, upper limbs (shoulders), lumbar spine, and hip joints.
I try to keep these circles lined up vertically as much as possible.

I'm not proud to admit it, but I used to stoop pretty badly like this. Is there anybody else whose posture is like this?

What I'd like you to note here is the movement of the pelvis! The pelvis is the point of this article.
First of all, let's take a brief look at the shape and location of the pelvis.

First, the yellow, red, and gray bones are collectively called the pelvis.

The large yellow bone is called the hip bone, and the upper side is called the ilium.
The ischium is the area that protrudes downward and has the hole.
In the picture, the gray part is the coccyx and the red part is the sacrum. It's a bone that can be touched above the crack in the buttocks.

I just want you to know about the coccyx and ischium now.

The ischium is a round and protruding as shown in the picture, so you can touch it easily.
When standing, the weight of the upper body is on the legs, but when sitting, it's on this ischium. Because of this shape, the ischium sways like a cradle to balance and stabilize the sitting position.

Next, I'd like to briefly write about the movement of the pelvis.

Simply put,
warped hips = pelvic forward
stoop = pelvic backward tilt

I think many people tend to lean backwards when playing the guitar.

When the weight on the ischium is leaning toward the back, the pelvis is tilted backward.
As the pelvis tilts backwards, the spine (chest/lumbar spine) bends, and the weight on the ischium goes onto the coccyx. Since the coccyx does not function to support the body, the weight of the upper body puts a load on the lumbar spine (spine) and back muscles.

The ideal sitting posture I think is
"a posture in which the weight is firmly placed on the ischium".

The weight of the head, arms, and torso is on the ischium, and the closer the center of gravity is, the more balanced and stable the sitting posture will be.

Here I recommend using a footrest!

If you place the foot that supports the guitar (right foot if you are right-handed) on a footrest of about 10cm, the center of gravity will naturally move forward, so you can keep the pelvis around the middle position, and the position of the guitar will rise as the height of the thigh rises. You can keep a stable sitting posture.
By the way, the stand I use as a footrest is from 100-yen shop, so if you want to try this, please get one.

By the way, Sound House also has a product like this!

K&M / 14640

If you have the opportunity to sit and play in public, it would be nice to have something solid like this.

Sound House also sells chairs geared towards guitarists!!

PLAYTECH / GSTH

This is a folding chair and a guitar stand as well...!
The seat cannot be adjusted, but it seems that the guitar and posture can be stabilized because there is a place to put your foot on the other side of the guitar stand.
I want to try this one out!!

You might say, "it's hard to stretch my back and it puts a strain on my back!" but you don't have to stretch your back hard, and on the contrary, stoop (pelvic backward tilt) seems to be comfortable, but it actually puts a strain on your lower back.

Muscles stretch and contract to exert their strength, so when you're stooped, your back muscles are in a stretched state.
Even if the muscles are stretched, that is, the muscles are not contracted and the muscles themselves are relaxed, the back muscles bend and the pressure on the lumbar region puts a load on the tendons and tissues, resulting in a strain on the bones and muscles.

First, focus on your ischium, making sure that your upper body is weight is on the ischium, and try to balance your sitting position. If you can look at your ischia and balance this, your back muscles will naturally rise without trying to stretch your lower back or whole back.
(If your ischium hurts, please use a cushion!)

About sitting cross-legged

Sitting cross-legged makes the lower back bend as the pelvis tilts backward and the center of gravity falls to the back of the ischium. This bad posture easily becomes a habit and it is said to be a long-term load on the spine causing spinal deformity and lower back pain.
In other words, if sitting cross-legged becomes a habit, it's not so good for your body.

But, maybe you still want to practice sitting with your legs crossed sometimes!

In such a case, using a cushion to raise the height of the buttocks and the pelvis can to reduce the burden on your body and I think it'll allow you practice for a long time.

However, since the distance between the guitar and your body a bit too far, you tend to stoop after all, and it's difficult to practice for a long time.
When practicing for a long time, I think sitting in a chair is still better for your body.
Actually, I often practice with legs crossed, but I have the impression that my body balance is unstable, my good posture is easily lost, my body isn't comfortable, and my concentration is easily interrupted.

Since I started practicing while sitting in a chair keeping my posture in mind, I feel more stable, and I don't feel distracted by my posture, and I think I have more time to concentrate on my work.

Having a "good posture" that doesn't burden your body is a point that affects your daily life when not playing the guitar, so please take care that you practice with good posture.

See you!