It is said that you should develop the habit of holding your chest out and abdomen in order not to have a small belly. Should they have stomachs when they walk or sit after meals?
There is no need to hold out your chest and abdomen. This will cause tension in the chest and abdomen, which is not good for your health. The key to maintaining the correct posture depends on whether you can keep your spine upright and make your whole body as relaxed and comfortable as possible. It is necessary to exercise the lower abdomen through exercise. The key to exercise is: temporary tension and lasting relaxation.