Breathing is a crucial aspect that strongly influences the expanding and condensing qualities of our body, mind and emotions.
Holding or suppressing breath usually tenses you up and closes you. Vice versa: When you are tensed, stressed, and shrink, you naturally tend to hold or suppress your breath.
Therefore, it is crucial to breathe deeply and smoothly during stressful situations (when it is good to be open and relaxed).

Our lungs and whole torso usually expand when we inhale and condense when we exhale. However, expanding and condensing is a different aspect. So, you can expand your body, mind, and emotions while you exhale and vice versa.

Anyway, breathing is closely linked to expanding and condensing quality. Therefore, it's easier to train expanding with inhaling and condensing with exhaling. Later, to be free, we train opposite, and in the end, breathing flows in an independent rhythm from expanding and condensing.