Elk P. answered 05/05/19
Host/Curator of Film Series, teaching assistant in film
I think it depends on the technique of the actor. I'd say in general the way it's filmed allows for the character to hold their breath for a brief amount of time: during, say, a close-up. But I'd say the relative distance of the camera to the body allows for the illusion of not breathing. Realistically the actor is probably still breathing during long shots (in distance and/or duration) because it's not as noticeable from afar. Good question!