You should not deliberately firm your abdomen, although it does retain a degree of firmness naturally from the uplifting action in your torso.

你不能使腹部僵硬，尽管腹部在躯干向上时要保持一定程度的自然收紧。

youdao

You should not deliberately firm your abdomen, although it does retain a degree of firmness naturally from the uplifting action in your torso.

你不能使腹部僵硬，尽管腹部在躯干向上时要保持一定程度的自然收紧。

youdao