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Breath Control and Blood Pressure

  1. Jun 14, 2018 #1


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    When I free dive (skin dive without a scuba air tank), I've noticed that by the time I get out of the water after about an hour (abalone diving or just recreational free diving), I feel like Jello and my blood pressure (BP) feels very low. I feel extremely relaxed and warm and happy. And after a target shooting session at the range, I feel the same way.

    Both activities involve breath control. In free diving, I hyperventilate a bit (not too much), and then I hold my breath for about a minute under water. Then I recover for about a minute on the surface to re-oxygenate, and do it again. At the shooting range, I take a deep breath, let about half of it out, and then stay at that diaphragm setting for the next few seconds as I squeeze the shot off. You are trying to minimize all muscle movements during that time.

    After both activities I feel a very noticeable relaxed state, and I'm pretty sure my BP is down quite a bit. I'd like to figure out how to translate this into my everyday life, since there are times at my EE work where it is very stressful and I can feel my adrenile level climb and I'm sure my BP is spiking.

    Does anyone have references to breath control and BP? The effect seems so significant from my personal experiences. I've done a bit of searching online, but I think I probably am not using the right search terms. Thanks folks. :smile:

    Last edited: Jun 14, 2018
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  3. Jun 15, 2018 #2


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  4. Jun 15, 2018 #3


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    I am have no doubt that a lot of this can involve long hours of training at breathing control or focusing your inner stuff.
    However, I am more interested in the biology I think would be underlying things like this.
    The diving part of your story reminded me of the diving response, when you hold your breath and wet your face, your body's oxygen supply system changes as if it were going to deal with prolonged submersion. It is for my purposes, a model physiological response. It produces some kind of low energy use metabolic state, take it easy kind of state, where you are relaxed and calm (as you should be if you are going to conserve energy).
    This is something conserved among mammals. It is probably the result of a autonomic nervous system state.

    The triggers for the diving response are:
    In more detail:
    Specific sensory triggers water on face and in nostrils.
    Signals go from nerves innervating the face (Trigeminal (V) nerve), to the hindbrain (central processing site for metabolic controls), then out the Vagus (X) nerve to the autonomic nervous system (involving lots of peripheral ganglia).
    I would hypothesize that effects of the autonomic nervous system were responsible for a lot of your experience.

    I would think of the diving response as a model of in what manner can a different functional autonomic state be invoked.
    Breath holding is also involved as a trigger of the diving response, which ties in with the shooting situation:
    I would expect that new triggers could be learned and the strength of old ones to be malleable, allowing one to find different ways of reaching equivalent final autonomic states.

    In a tense situation, maybe holding your breath and splashing some cold water on your face/nostrils will invoke some of the diving response for you.
  5. Jun 15, 2018 #4
    I think it'll be 'breath holding CO2 vasodilator' or something like that.

    Ps.: I have no relevant knowledge: I have just picked up the google challenge again...
  6. Jun 15, 2018 #5


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    Breathing control center neurons that promote arousal in mice.
    Yackle K, Schwarz LA, Kam K, Sorokin JM, Huguenard JR, Feldman JL, Luo L, Krasnow MA.
    Science. 2017 Mar 31;355(6332):1411-1415. doi: 10.1126/science.aai7984. Epub 2017 Mar 30.

    "Although breathing is commonly viewed as a simple autonomous function that sustains life, it has long been known to influence higher order behavior and thinking (1). Slow controlled breathing is used by practitioners of pranayama yoga and other forms of meditation to promote mental calming and contemplative states, and it is used clinically to suppress excessive arousal and stress such as certain types of panic attacks (2,3). While the effect of breathing on behavior and mental state could easily be indirect, there could also be more direct connections and impact of the breathing center on higher order brain function (4), as demonstrated here. ...

    We propose ... This respiratory corollary signal would thus serve to coordinate the animal’s state of arousal with the breathing pattern, leaving the animal calm and relaxed when breathing is slow and regular, but promoting (or maintaining) arousal when breathing is rapid or disturbed."
  7. Jun 15, 2018 #6

    Fervent Freyja

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    Couldn't find anything that the Navy has offically published, but Box Breathing is a technique endorsed by the Navy SEALS.
  8. Jun 17, 2018 #7


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    Any technique that increases your parasymphatetic tone and reduces your symphatetic tone (which is why it means to relax in terms of ANS) would typically reduce HR and reduce blood pressure by various other mechanisms likes vasodliation.

    As for the physiology in yoga techniques i think this is complex. Some have suggested that deep breathing (high amplitude breathing) may stimulate the baroreceptors to increase the vagus tone, as for nose breathing as opposed to mouth breatthing i recall having seem some theories that the vibration in nostrils stimulate the vagus nerve. And due to a biological left/right assymmetry of the innervation of the vagus nerve on the heart, left vs right nostril blocking technique has different effects. right vagus nerve mainly innervates the SA node, and thus reduces heart rate. But left vagus innervates the AV node more, and thus left vagus eletrical stimulation is a possible alternative to medication against some arrythmias caused by increased autonomy of other pacemakercells. Here right vagus stimualtion would simlpy cause bradychardia rather than merely reducing arrythmia.

    Other than this simply focusing on harmonic and calm breathing may be a cognitive "trick" to make your brain getting a pause from stressful thoughts. Ie. instead of just "stop thinking about stressful things", an easier way is to try to focus on something trivial, such as breathing. Just like the magicians tricks to make you not see, is to make you look at something else :)

    There is no question this has some good physiological grounds but it seems a complex system, with more than one mechanism involved. Its both cognitive mechanism and physiological/biological mechanisms working together.

  9. Jun 17, 2018 #8


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    As for focusing on trivial things. Another thing i consistently find relaxing is soldering :) IF you have 20 projects going on in your head normally, and if you end up in a situation where you like have to solder some conenctors. Just focusing on ONE wire at a time, is as good as yoga to me ;) Its like a perfect excuse to clear it from the 20 projects and just do one wire at a time.

  10. Jun 19, 2018 at 12:45 AM #9


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    Also known as "Taking a Break."
    Edit: or "Decompressing."
    Last edited: Jun 19, 2018 at 1:26 AM
  11. Jun 22, 2018 at 9:38 PM #10
    You might want to talk to the RESPeRATE people. The have a machine that measures your breathing rate because when you lower it your blood pressure drops.
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