Triggering dive reflex (DR)

[pat fish]

I do have strong DR on competitions, but hard to get them in training. I did a max dynamic today. Preparation: Stretching. No warmup except 3x negatives dry with some diaphragm stretching. And 10min of laying down and focusing before the performance. Very slow breathing before the dive. And the dive: Cool water. Very focused but maybe too comfortable ?... Everything went well -I waited for the DR (pain/first urge to breath) and... it only came late at 75m. I still made it to a respectful distance but no pb and I was on the edge. And - no burning legs. That made me worry.

What can be done to ensure early and strong DR?

How important is adaptation from regular exposure to high levels of CO2? What gives best adaptation? High peaks or long exposures?

What can be done to work mentally on getting early DR?

Pat

[Parables]

Great question. While I don't know the answer if I may tack on a supplemental question that hopefully can be answered in one swoop with yours. When you say (pain/urge to breath) is that a burning pain in your chest. When I hit 50m I get a pain in my chest with a firery burning feeling. Can I plow through this? Or is this a sign of something bad. My warm up is comparable to yours but much less involved. I need to make it more like yours it seems. Thanks for the post. Look forward to the replies.

[fpernett]

Hi Pat

I don't know if I have the answer, but here is my opinion

I think that your DR in competition is due to stress, I think that a little bit of stress is not so bad, and can increase your DR.

It may sound stupid, but the best way to have a good DR is diving. I don't think too much in CO2, but in O2 stores to kick the diving reflex.

One exercise that I use to enhance DR is Murat-Style dynamics. Don't do any warm up. Start the dynamic as an static, if you have a heart rate monitor, your buddy can tell you when your heart rate have a good drop off, or feel your heart contractions and star the dynamic until you feel it very low.

Another way is by only training maximal dynamics without warm up. I think that if your body has to face an extreme oxygen depletion, it will use it an intelligent way (that's the main reason of the DR)

[pat fish]

Frank,
Thank you for the input. A good DR in competition situation can only be explained by stress, right?. I followed the posts by Sebastian M. about that before. Very interesting and logic. Catecholamine hormones are released, peripheral vasoconstriction is activated and peripheral muscles therefore switch to anaerobic metabolism. So, oxygen is preserved for the central nervous system. For the dive I described yesterday, I tried to imagine going into very cold water and having a very tough task ahead. Nevertheless I waited for the DR and it came very late. I felt stressed when I started the dynamic, but somehow relaxation set in and my legs "didn't close"...
Interesting that you say Frank that you don't think too much in CO2, but in O2 stores to kick the diving reflex. How come?

[fpernett]

Hi Pat
Well, I don't think competition stress is only factor, there are other issues like your previous training. Stress can be helpful but also can ruin your dive.

If you're training to have a strong DR, you don't need to care much about CO2, let me explain:
A strong DR isolate the muscle cells from peripheral circulation, it prevents that O2 coming from circulation enters the cell, but also keep the CO2 produced in the cell. Many experimental trials have found that the EtCO2 is lower than expected specially in CW dives, and is possible also to have some CO2 transfer reversal in the lungs. (Craig, A.B., Jr. and W.L. Medd, Oxygen consumption and carbon dioxide production during breath-hold diving. J Appl Physiol, 1968. 24(2): p. 190-202.)(Ferretti, G., et al., Alveolar gas composition and exchange during deep breath-hold diving and dry breath holds in elite divers. J Appl Physiol, 1991. 70(2): p. 794-802.)(Boutilier, R.G., J.Z. Reed, and M.A. Fedak, Unsteady-state gas exchange and storage in diving marine mammals: the harbor porpoise and gray seal. Am J Physiol Regul Integr Comp Physiol, 2001. 281(2): p. R490-494.)
So the starting CO2 will affect mainly your respiratory center, and flow regulation in heart, lungs and brain, not diving muscles. With strong hyperventilation, the urge to breath will come late, but the alkalosis impairs the brain blood flow, and the hemoglobin saturation curve shifts to the left side, so less oxygen available to brain and BO. On the other hand, strong hypoventilation will make you have earlier contractions, in CW more narcosis but better blood flow.
I think you don't need to change the way you breathe. I think the best way to go is with Normal CO2 (also normal pH).
This is just my opinion.

[pat fish]

Hi Frank,
Of course stress is not the only factor. And of course it can be unfavorable also. But shutting of peripheral perfusion is mainly triggered by activation of sympathetic nervous system (stress) or coldness I guess.
What you say is: initially elevated CO2 levels wouldn't affect peripheral constriction too much. That would correspond to Sebastian's thesis of no preparation at all for a strong DR, am I getting it right? If it is true that a bigger spread of CO2 between initial levels (not alcaline though..) and elevated levels is contributing more to a good DR than a smaller spread (start with elevated CO2), this would corroborate your advise of starting with normoventilation.
What I believe is: Getting a good DR isn't as much of a topic in constant weight as it is in dynamics. On a good sinking phase in constant weight, the increasing water pressure in head down position helps a lot to trigger good DR.

[naiad]

Originally Posted by fpernett

I think that your DR in competition is due to stress, I think that a little bit of stress is not so bad, and can increase your DR.

It may sound stupid, but the best way to have a good DR is diving. I don't think too much in CO2, but in O2 stores to kick the diving reflex.

One exercise that I use to enhance DR is Murat-Style dynamics. Don't do any warm up. Start the dynamic as an static, if you have a heart rate monitor, your buddy can tell you when your heart rate have a good drop off, or feel your heart contractions and star the dynamic until you feel it very low.

Another way is by only training maximal dynamics without warm up. I think that if your body has to face an extreme oxygen depletion, it will use it an intelligent way (that's the main reason of the DR)

I don't do much of a warm-up for dynamics. Yesterday in the competition I did my nicest ever 50m dynamic, it was effortless and I could have done more, but I came up because I wanted to finish clean and it is close to my max. The warm-up was minimal, just a few 10-20m dynamics a few minutes before it.

Lucia

[fpernett]

Originally Posted by pat fish

Hi Frank,
Of course stress is not the only factor. And of course it can be unfavorable also. But shutting of peripheral perfusion is mainly triggered by activation of sympathetic nervous system (stress) or coldness I guess.
What you say is: initially elevated CO2 levels wouldn't affect peripheral constriction too much. That would correspond to Sebastian's thesis of no preparation at all for a strong DR, am I getting it right? If it is true that a bigger spread of CO2 between initial levels (not alcaline though..) and elevated levels is contributing more to a good DR than a smaller spread (start with elevated CO2), this would corroborate your advise of starting with normoventilation.
What I believe is: Getting a good DR isn't as much of a topic in constant weight as it is in dynamics. On a good sinking phase in constant weight, the increasing water pressure in head down position helps a lot to trigger good DR.

Yes, Pat, that is. I think is better to start a maximal dynamic without a huge change in your acid-base state. I think a good DR is critical in all disciplines. There are many more factors in CW that help you to have a good DR. But still is a lot people that can get a good DR on a CW dive. That's why I agree with the no-warm up approach.
@ Lucia, congratulation. You should try with no warm up at all!