Out of breath
Definition 1 of 1
Pro Tip 1/3Physical Exertion
Use after activities like running or climbing stairs to describe breathing difficulty. 
She climbed the steps quickly and was out of breath at the top.
Pro Tip 2/3Emotional Intensity
Can describe strong emotions like excitement or shock that make you breathe faster. 
He was out of breath when he received the surprising news.
Pro Tip 3/3Non-literal Use
Sometimes used metaphorically, not because of literal breathing problems. 
The final twist in the movie left me out of breath.