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Theory questions

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Hawaiian transplant...
Sep 9, 2002
How do you know whether your training is:

A) Increasing your tolerance to CO2 & the discomfort of contractions.


B) Increasing the eficiency of your body's utilization of air & the ability to relax.

I know training does a little of both, but since I think of my static as my "theoretical max" for dynamics & spearfishing, I would like to emphasize on B since A could be harmful. As many of you know, sambas or BOs in spearfishing often carry much heavier consequences than in pure freediving.

I'd like to get better & am trying to work out a training schedule, but going through all the posts on this board is mind-numbing... :(
Hi fuzz,

I don't know for sure the best way to achieve your goal, maybe EricF will chime in, but for dry land training, I focus empty lung statics and passive exhale apnea walking. Both of these are based on info from this forum re enhancing tolerance for low o2 without building a lot of co2 tolerance. I kind of like my mediocre co2 tolerance, good insurance. When I push either technique, I get a hot flush feeling in my limbs that I associate with low o2, and I don't have to fight the co2 induced urge to breath so hard. In apnea walking, I can tell I get very close to falling down, so I'm pretty sure my o2 level is getting low. Interesting side effect, doing a series of passive exhale apnea walks dramaticly increases my distance on full lung walks. Not sure why.

Do a search on FRC diving , I think that would bring up some good stuff.

Will do, thank you :)

How can you tell the diff between low o2 tolerance & co2 tolerance?
To tell the truth, I'm not sure how to tell the difference. I'm trying to train in the direction of low o2. Low o2 produces (I think) the hot flush, lactic acid burn , tingles, shaky legs, want to fall down sort of feeling. High co2 just creates a huge urge to breath. Doing full lung statics I don't get the low o2 symptoms, just a huge urge to breath. Doing full lung apnea walks, I get some low o2 symptoms before the urge to breath stops me. Doing passive exhale apnea walks, I stop because of a combination of urge to breath and very strong low o2 symptoms along with fear of passing out.
Because I've never pushed a static beyond 4:30 , I am assuming a relatively mediocre co2 tolerence, which I 'd just as soon keep. I hope what I'm doing will build low o2 tolerence and improve my bottom time without decreasing my safety margin. I won't know till summer.

Hope this helps.


Oh yes, there is another EricF suggestion that I have played with. Full exhale, hold to the first contraction, then inhale very slowly. He does it by packing, I just inhale intermittantly and as slow as possible. This brings on low o2 symptoms and allows you to hold on to them for quite a while. Seems like a good technique to train for low 02.
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