Mewing is basically putting the tongue on the roof of the mouth.    Now does the force of the tongue actually push the maxilla forward advancing it over time?  It’s possible.  But I think the majority of the benefits of mewing are due to the fact that actively putting the tongue on the roof of the mouth achieves lateral pterygoid muscle activation.   You see it’s been shown in orthodontal work via forced mouth opening and bite jumping appliance that lateral pterygoid muscle activation can simulate cartilage and endochondral ossification of the mandibular condyle.

The lateral pterygoid muscle attaches directly to the cartilage and by stimulating and activating by placing the tongue on the roof of your mouth you’re constantly pulling on the cartilage throughout the day.  Now it’s possible that mewing also has other benefits.  But if a large portion of mewings benefits are due to the lateral pterygoid muscle activation then it doesn’t matter if you’re mewing if you’re instead doing something else that activates the lateral pterygoid muscle such as talking or chewing.  But placing the tongue on the roof of the mouth is is something that can be done during sleep and I have successfully done this during sleep.  Thus your cartilage can be stimulated more frequently.

So, to apply the mewing principle to the other parts of the body?   How do we make alterations in posture and position such we can stimulate cartilage and growth throughout the day?

Chest up, shoulders back.  Shoulders back activates the upper back muscles.  Chest up activates the lower back muscles.  Now you don’t have to do this in a ridiculous way.  You just have to do enough so that the muscles are activated.  If if you at the the above pictures you see that most of the back muscles are angled upward so if you achieve muscle contraction it will pull all the spinal components upward too.

Now you may think if I round my shoulders forward and round my back that will stretch the back components too?  But if you do that the back will be stretched in an an unnatural way and out of alignment?  ie. scoliosis.  Like I said the muscles are already slanted and will pull upward if activated and it will pull in proper alignment.

If you want better results than get stronger back muscles(stronger lateral pterygoid muscle for the jaw).   Unfortunately, the back muscles do not attach directly to the cartilage but they do attach to soft tissues that will indirectly pull on the spine.  You can’t really mimic this with a back device you really want to do it yourself to achieve back muscle activation.

Now height gains won’t be much but a lot of people sit down for a lot of the day and don’t have good posture.  On an individual level the height gains probably won’t be significant(unless you have incredibly strong back muscles) but if everyone did it there would probably be small significant height gains.

If you’re worried about looking ridiculous then just find the minimal amount to pull your shoulders back and your chest up to achieve back muscle activation,  Ideally you’d want to sleep in this posture so your muscles pull while you sleep to.  So you would sleep on your back with your shoulders back and your back slightly arched.  Now you’re trying to sleep so you want to find the minimal amount of effort you can do to do this.  It cannot be achieved with a device as that will reduce muscle activation.

So think tongue on the roof of your mouth, shoulders back, chest up(or back arched).  Ideally while you sleep too.