It’s a signal to your own body to relax. Controlling your breathing carefully influences your sympathetic and parasympathetic nervous systems, which are controlling how activated your body is in a complicated dance.
It’s like how lying down and closing your eyes is a signal to your body to let you fall asleep at night.
Well, it’s called the 4-7-8 technique, where you inhale for 4 seconds, keep it in for 7 seconds, and exhale for 8 seconds. From what I’ve read, when you use this technique, it tells your brain(which is in fight-or-flight mode) that there’s no need to panic, and you can go into flight mode aka feel good.
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