It doesnt matter if it were Inhaling or exhaling.. Read what the doctor wrote...
During normal respiration, the chest wall expands a small amount and the lung expand to remain constantly in contact no matter how fast or sharply you breath in. The diaphragm moves up and down a good deal as well, but again, the lungs are in continual contact with the diaphragm. The lungs never separate from chest wall

There is always a constant vacum inside the cavity, until an arrow is put through it, that is. No matter how hard you breathe, in or out, there are still attached.