re: #3, I wish I had a clear answer for you. I believe the Navy Seals use box breathing (4 sec each for inhale, hold, exhale, hold) because it puts them in a calm, high-energy state. Those two descriptors may seem paradoxical, but it's a state I've manage to put myself in before, say, a sales call or public talk. You want high energy to raise the energy level of the audience, but you want calm to be making better decisions in a quickly changing situation.
That differs, I think, from a physiological sigh where you're just trying to relax, which the longer exhale vs inhale gets you.
James Nestor talks about the effects of breath holds in his book "Breath", and one thing he brings up is "carbon dioxide therapy"; ie exposing yourself to mildly elevated levels of carbon dioxide for brief periods was once thought to be beneficial, and he cites people claiming the research has not been disproven. One of the supposed benefits (I'm not a doctor!) is anxiety reduction, similar to how people might tell someone who is panicking to breath with a brown paper bag over their mouth.
re: #3, I wish I had a clear answer for you. I believe the Navy Seals use box breathing (4 sec each for inhale, hold, exhale, hold) because it puts them in a calm, high-energy state. Those two descriptors may seem paradoxical, but it's a state I've manage to put myself in before, say, a sales call or public talk. You want high energy to raise the energy level of the audience, but you want calm to be making better decisions in a quickly changing situation.
That differs, I think, from a physiological sigh where you're just trying to relax, which the longer exhale vs inhale gets you.
James Nestor talks about the effects of breath holds in his book "Breath", and one thing he brings up is "carbon dioxide therapy"; ie exposing yourself to mildly elevated levels of carbon dioxide for brief periods was once thought to be beneficial, and he cites people claiming the research has not been disproven. One of the supposed benefits (I'm not a doctor!) is anxiety reduction, similar to how people might tell someone who is panicking to breath with a brown paper bag over their mouth.
https://www.amazon.com/Breath-New-Science-Lost-Art/dp/073521...