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RMV Spinoff from Accident & Incident Discussion - Northernone - aka Cameron Donaldson

Discussion in 'Marine Science and Physiology' started by johndiver999, Mar 20, 2019.

  1. markmud

    markmud Self Reliant Diver--On All Dives. ScubaBoard Supporter

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    Hi johndiver999,

    May I add that no human being can overcome the laws of physics and the laws of chemistry.

    For every action there is an equal but opposite reaction. For this discussion, it may not be in direct proportion or linear, but something will change with your physiology. A chemical imbalance will occur. Your body will react and cause more side effects.

    As @rsingler has written add nauseum: to what end (paraphrased)? Bragging rights? Or, the Russian roulette hammer coming down on a live primer and charged cartridge?

    Thanks to those who posted on this thread. Especially, @rsingler and @Compressor. It has been educational.

    markm
     
    Compressor and Sam Miller III like this.
  2. markmud

    markmud Self Reliant Diver--On All Dives. ScubaBoard Supporter

    # of Dives: 200 - 499
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    @rsingler and @Compressor,

    I have a scenario that I would like to run by the two of you.

    A diver is in decent physical condition. He/she exercises (cross trains) but is not at an athletes level of condition. This diver has an above average vital capacity, tidal volume, and etc. Good cardiovascular numbers.

    This diver practices abnormal breathing techniques to decrease his/her SAC/RMV for scuba diving. Their bodies have acclimated somewhat to the side effects of higher than normal blood CO2 levels.

    Now, life gets in the way. They are busy at work, a new baby, a sick relative and/or etc.

    They stop cross training. Their physical condition decreases as they have become sedentary.

    If this diver jumped in the water and tried to dive as they did when they were at their peak (acclimated to high CO2) and tried to dive with a low SAC/RMV, would the effects of high CO2 be more pronounced? In other words, they are using abnormal breathing techniques to "sip" gas as they had when they were physically fit.

    thanks,
    markm
     
    Sam Miller III likes this.
  3. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

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    With the caveat that this is pure conjecture, I'd say, "A little of both." I think when the hypothetical diver got back to it, his headaches might be temporarily worse, but his susceptibility to a CO2 hit wouldn't be, but only because when he was fit, that hadn't conferred any resistance to CO2 toxicity. He was as close to the edge when he was skip breathing with abandon, as he is now that the practice makes him feel "off."
    You can't train out of susceptibility to a CO2 hit, even if skip breathing doesn't gives you as bad a headache any more. Two different mechanisms. Headache is vasodilation/vasoconstriction-related, akin to a migraine. The narcotic effect is central in your brain.
     
    markmud likes this.
  4. Storker

    Storker Divemaster

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    And for some of us, it's associated with having to bend our neck backwards, which we have to do if we're in horizontal trim and want to look forward. Unlike how it is topside, when we're standing upright.

    Basically, slightly overworked neck muscles. Not uncommon for desk jockeys.
     
    markmud likes this.
  5. rsingler

    rsingler Scuba Instructor, Tinkerer in Brass Staff Member ScubaBoard Sponsor

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    Simple solution, @Storker !
    Just dive out of trim! :poke::rofl3:
     
    Storker, Dan and markmud like this.
  6. markmud

    markmud Self Reliant Diver--On All Dives. ScubaBoard Supporter

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    Hoo-aa ouch. I know that feeling.

    m
     
  7. RayfromTX

    RayfromTX Student Of Gas Mixology Staff Member ScubaBoard Sponsor

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