A tai chi teacher will tell the students to "tuck in your chin" or "pull back your chin". What the heck does that mean? Our spine an essential part of our posture and our health. When your teacher talks about your chin, it's about posture. However, I have seen students get into some really grotesque postures when learning about this.
I have developed a simple technique to help students understand this. This takes some sensitivity, so I don't even mention this to beginners. Beginners don't have the ability to understand or even sense what is happening to their bodies.
Start by slouching a little bit, let your shoulders move forward, and bend your head a little bit. Now, straighten your head up a little bit and pull your chin back. This doesn't mean to push your whole head back. When you pull your chin back, let your head pivot around an axis near the top of the neck. This straightens out the upper part of your spine and your neck.
Your shoulders will feel some tension. Give in to the tension and let your shoulders pull back up. The crown of your head will naturally rise up. Now it makes sense to talk about a thread connecting the crown of your head to the heavens.
This improves your posture. And it's all because you tucked in your chin.
© 2013 Eric Borreson