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Way of the deep end: Seb (Subs) Murat aims for No-Limits Record
- Thread starter sebastien murat
- Start date
Thread Status: Hello
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It can take a long time to get an up-to-date response or contact with relevant users.
It can take a long time to get an up-to-date response or contact with relevant users.
About those calculations, what variables came to mind?
I guess that with increasing experience the optimal volume changes. For instance a beginner feels more comfortable -psychologically- with full lungs diving deep. Diving any below full does give him (more) anxiety and therefore limit the depth he may reach. Tolerances to cold and the right preparation and food will help to reduce suit thickness.
David Carrera has dived to -99m in CWT with a mask and just a normal full breath, without packing. I noticed myself that diving without packing is much more relaxed because the start is much more relaxed.
Equipment and depth also makes a big differences.
Personal body shape? Lung size to weight to volume ratio?
What else?
Nice find Hteas.
Kars,
Again the most obvious example is a person with a lung volume of 100L. Since you can overcome only about 25kg-force of buoyancy with a monofin, this person would need 75kg of weight in order to get down. On the bottom the 100L would be compressed to 10L at 90m. This means the person would have to overcome 65kg of negative buoyancy on the ascent. They would never get off the bottom. Thus 100L is not the ideal volume.
Using this same example, the maximum volume you could even ascend with would be a lung volume of 50L. This would give a starting ballast of 25kg, requiring the full max of 25kg-force to get down (with 25kg of positive buoyancy), assuming no wetsuit and no buoyancy in the monofin. At 90m the buoyancy would then be 5kg, requiring an ascent against 20kg of negative ballast. Ascending for most of the ascent with 20kg of negative ballast would cause leg failure and BO very deep. So 50L is still way too much volume.
Thus, the rule that more is better is clearly false. There must be thus some ideal lung volume, and this ideal lung volume would vary dramatically based on the experience, body type, equipment, and training of the diver. But more is not necessarily better.
Keep in mind also that the more volume you start with, the more energy it takes to get down to sink depth. This extra CO2 generated on the descent will greatly worsen the narcosis on the ascent. So in addition to energy savings or loss, the buoyancy configuration also affects narcosis, blood shift and many other variables.
So even if you could get down with 35L of air, you would probably black-out from CO2 narcosis on the early ascent.
Again the most obvious example is a person with a lung volume of 100L. Since you can overcome only about 25kg-force of buoyancy with a monofin, this person would need 75kg of weight in order to get down. On the bottom the 100L would be compressed to 10L at 90m. This means the person would have to overcome 65kg of negative buoyancy on the ascent. They would never get off the bottom. Thus 100L is not the ideal volume.
Using this same example, the maximum volume you could even ascend with would be a lung volume of 50L. This would give a starting ballast of 25kg, requiring the full max of 25kg-force to get down (with 25kg of positive buoyancy), assuming no wetsuit and no buoyancy in the monofin. At 90m the buoyancy would then be 5kg, requiring an ascent against 20kg of negative ballast. Ascending for most of the ascent with 20kg of negative ballast would cause leg failure and BO very deep. So 50L is still way too much volume.
Thus, the rule that more is better is clearly false. There must be thus some ideal lung volume, and this ideal lung volume would vary dramatically based on the experience, body type, equipment, and training of the diver. But more is not necessarily better.
Keep in mind also that the more volume you start with, the more energy it takes to get down to sink depth. This extra CO2 generated on the descent will greatly worsen the narcosis on the ascent. So in addition to energy savings or loss, the buoyancy configuration also affects narcosis, blood shift and many other variables.
So even if you could get down with 35L of air, you would probably black-out from CO2 narcosis on the early ascent.
The other thing is that ascent is not some mirror image of descent physiologically speaking: the dynamics of the exercise and dive response vary with buoyancy and lung volume. Large lung volumes,presumably = high buoyancy lead to a high burn rate and you can't just shut the tap off willy nilly. One should make every attempt to minimize burn rate during descent. Once the dive response is established then you can pretty much sprint.... I., if you can cut it.
Talking about DR,
Sebastien maybe you can say something about this.
If I do a dynamic my limit is the O2 to my brain. I come up without any leg burn doing something like 125 - 150m. When I do an empty lung static+dynamic no fins(40 sec + 67m) I do have a little burn. Many of my fellow freedivers describe much more burn starting earlier (after 70ish). They also swim further. My static pb is 7'. I did experiment with apnea jogging and running. Jogging until first contraction and then sprint the rest. Doing this leaped my 'walking dynamic' pb by a leap (+25%) with room to spare, clear head, and au contraire to previous 'walks/jogs' a nice burn in the muscles used.
I suspect body type and shape has much to do with how strong and effective the bloodshift is. Mine is: skinny, slender, tall, fairly high base condition. In my mind I picture that in my thin long limbs the blood has an easier time reaching and supplying the muscles closer to the stream. Having a good condition I think I also have a high blood 'bandwidth' to my muscles, allowing me to perform at a high pace continuously without burning up. Countering this I figured I need to wait for the DR to manifest and then make sure I demand more than my bloodstream can handle in order to have my muscles perform in 'anaerobic mode'.
What do you think of all this?
BTW I share your view on the start of the dive. I like to say to others that the trick is to not only be relaxed and slow at the surface, but to retain it in your dive. It's nearly impossible to get relaxation back while diving.
Sebastien maybe you can say something about this.
If I do a dynamic my limit is the O2 to my brain. I come up without any leg burn doing something like 125 - 150m. When I do an empty lung static+dynamic no fins(40 sec + 67m) I do have a little burn. Many of my fellow freedivers describe much more burn starting earlier (after 70ish). They also swim further. My static pb is 7'. I did experiment with apnea jogging and running. Jogging until first contraction and then sprint the rest. Doing this leaped my 'walking dynamic' pb by a leap (+25%) with room to spare, clear head, and au contraire to previous 'walks/jogs' a nice burn in the muscles used.
I suspect body type and shape has much to do with how strong and effective the bloodshift is. Mine is: skinny, slender, tall, fairly high base condition. In my mind I picture that in my thin long limbs the blood has an easier time reaching and supplying the muscles closer to the stream. Having a good condition I think I also have a high blood 'bandwidth' to my muscles, allowing me to perform at a high pace continuously without burning up. Countering this I figured I need to wait for the DR to manifest and then make sure I demand more than my bloodstream can handle in order to have my muscles perform in 'anaerobic mode'.
What do you think of all this?
BTW I share your view on the start of the dive. I like to say to others that the trick is to not only be relaxed and slow at the surface, but to retain it in your dive. It's nearly impossible to get relaxation back while diving.
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Hi Kars,
I'll just throw thoughts out as they come to me.
Its difficult to conclusively explain your condition as there are a multitude of factors to consider, but the DR most likely has lots to do with this. I know of very few instances where locomotor muscle failure occurred before loss of consciousness, so that in itself says a lot about the scope in performance reserve potential. Certainly, early morning dives, no (physical) warm-up, and cold water will shift the balance to a greater reliance on anaerobiosis. On the other hand, even with no DR at all, i.e., breathing, if one sprints fast and long enough you'll obviously burn-up, so a DR is not a pre-requisite for a burn. The issue, I guess, essentially has to do with whether you sprint during the latter part of a swim or do so at a constant, sluggish pace. Its hard to know to what extent the locomotors still receive blood during a pronounced DR, i.e., transition from static to dynamic, and whether sprinting could be counterproductive by increase the O2 burn rate, but presumably you can determine this through lots of well controlled trials; alternatively, check to see if your bradycardia reverses. If it doesn't then your O2-cost per unit distance is likely to remain fixed at this time, irrespective of how fast you swim. The bottom line: if you don't have a particularly (genetically) pronounced DR then you stand to gain the most by starting your dives from the most depressed metabolic state possible. Then and perhaps only then might you you find your maximal performance potential, as evidenced by close to locomotor failure.
I'll just throw thoughts out as they come to me.
Its difficult to conclusively explain your condition as there are a multitude of factors to consider, but the DR most likely has lots to do with this. I know of very few instances where locomotor muscle failure occurred before loss of consciousness, so that in itself says a lot about the scope in performance reserve potential. Certainly, early morning dives, no (physical) warm-up, and cold water will shift the balance to a greater reliance on anaerobiosis. On the other hand, even with no DR at all, i.e., breathing, if one sprints fast and long enough you'll obviously burn-up, so a DR is not a pre-requisite for a burn. The issue, I guess, essentially has to do with whether you sprint during the latter part of a swim or do so at a constant, sluggish pace. Its hard to know to what extent the locomotors still receive blood during a pronounced DR, i.e., transition from static to dynamic, and whether sprinting could be counterproductive by increase the O2 burn rate, but presumably you can determine this through lots of well controlled trials; alternatively, check to see if your bradycardia reverses. If it doesn't then your O2-cost per unit distance is likely to remain fixed at this time, irrespective of how fast you swim. The bottom line: if you don't have a particularly (genetically) pronounced DR then you stand to gain the most by starting your dives from the most depressed metabolic state possible. Then and perhaps only then might you you find your maximal performance potential, as evidenced by close to locomotor failure.
"The issue, I guess, essentially has to do with whether you sprint during the latter part of a swim or do so at a constant, sluggish pace."
For these dives I have a slow (50s/50m) and after 50m and 1st contraction less slow pace (40s / 50m).
I have not noticed my HR to go up much during Dynamic. In static I have a nice drop:
First 40s linear from 90 to about 55 then a curve down to 35 (2'30" - almost coincide with 1st contraction) and then a linear gradual incline to 39 at 5'. In a graph it looks very metamathematical. :hmm
I have not recorded my HR during dynamic.
But I did during some empty lung stuff, doing forced exhale dives (2'+) to -5m and the HR went much lower than the monitor could detect. A friend counted my neck artery's pulse and counted 8 or 9 slow beats / 30s. ~17bpm.
When I do these I always enjoy a huge feeling of blood shift at the surface, relaxing skin, lowering of blood pressure and returning blood to my limbs, which I enjoy very much.
Doing deep diving it's a bit of a mixed bag. Doing a slow CWT dive in a cold lake, 1'40 - 42m, the lowest recorded heart rate was 33bpm.
Looking back to successful dynamics, I notice these were the ones where I managed to swim in a more relaxed way.
The idea I have for now is that when I'm too tense in my body, due to feeling the need to consciously control my monofinning (inconsistent technique) and that this is consuming a lot of O2 - keeping metabolic rates up - delaying DR and preventing a deep DR.
This also reminds me of Dolphins who can hold their breath for over 15min when relaxed, and hardly manage 20 seconds when stressed.:rcard <unproven claim> :ban
What do you think?
Sorry for the sidetrack, it's just a sort of burning question I have for over 5 years. It's hard for me to understand why my bodies reaction deviates so much, being out of balance. :duh
Happy New year!
For these dives I have a slow (50s/50m) and after 50m and 1st contraction less slow pace (40s / 50m).
I have not noticed my HR to go up much during Dynamic. In static I have a nice drop:
First 40s linear from 90 to about 55 then a curve down to 35 (2'30" - almost coincide with 1st contraction) and then a linear gradual incline to 39 at 5'. In a graph it looks very metamathematical. :hmm
I have not recorded my HR during dynamic.
But I did during some empty lung stuff, doing forced exhale dives (2'+) to -5m and the HR went much lower than the monitor could detect. A friend counted my neck artery's pulse and counted 8 or 9 slow beats / 30s. ~17bpm.
When I do these I always enjoy a huge feeling of blood shift at the surface, relaxing skin, lowering of blood pressure and returning blood to my limbs, which I enjoy very much.
Doing deep diving it's a bit of a mixed bag. Doing a slow CWT dive in a cold lake, 1'40 - 42m, the lowest recorded heart rate was 33bpm.
Looking back to successful dynamics, I notice these were the ones where I managed to swim in a more relaxed way.
The idea I have for now is that when I'm too tense in my body, due to feeling the need to consciously control my monofinning (inconsistent technique) and that this is consuming a lot of O2 - keeping metabolic rates up - delaying DR and preventing a deep DR.
This also reminds me of Dolphins who can hold their breath for over 15min when relaxed, and hardly manage 20 seconds when stressed.:rcard <unproven claim> :ban
What do you think?
Sorry for the sidetrack, it's just a sort of burning question I have for over 5 years. It's hard for me to understand why my bodies reaction deviates so much, being out of balance. :duh
Happy New year!
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Kars,
I'm sorry but I'm not quite sure I understand your question, specifically. What exactly are you asking?
Also, in regards to relaxed vs. under duress dives and BH ability: in all experiments involving forced/restrained diving animals BH ability is prolonged compared to unforced diving; its just not comfortable. I keep seeing this myth recirculated. It is absolutely not true and is a high risk position to adopt.
This is readily understandable: distress accentuates the DR, which conserves O2 stores, but limits effective CO2 storage, thereby resulting a build-up of blood CO2. The result is a strong discomfort brought on by a CO2-driven urge to breathe. But this does not necesasarily mean that BH can't be witheld. This is also the reason why exercise during breath-hold with little to no DR, e.g., terrestrial apneas, does not result in a strong urge to breathe, i.e., CO2 can be readily redistributed in working/vasodilated muscle. This is a fools paradise because O2 is consumed at also consumed at a rapid rate, so that the safe hypoxic reserve margin and tolerance is reduced. Do not be fooled!
I'm sorry but I'm not quite sure I understand your question, specifically. What exactly are you asking?
Also, in regards to relaxed vs. under duress dives and BH ability: in all experiments involving forced/restrained diving animals BH ability is prolonged compared to unforced diving; its just not comfortable. I keep seeing this myth recirculated. It is absolutely not true and is a high risk position to adopt.
This is readily understandable: distress accentuates the DR, which conserves O2 stores, but limits effective CO2 storage, thereby resulting a build-up of blood CO2. The result is a strong discomfort brought on by a CO2-driven urge to breathe. But this does not necesasarily mean that BH can't be witheld. This is also the reason why exercise during breath-hold with little to no DR, e.g., terrestrial apneas, does not result in a strong urge to breathe, i.e., CO2 can be readily redistributed in working/vasodilated muscle. This is a fools paradise because O2 is consumed at also consumed at a rapid rate, so that the safe hypoxic reserve margin and tolerance is reduced. Do not be fooled!
Seb,
Your comment "CO2 can be readily redistributed in working/vasodilated muscle." is interesting
I don't have a medical background so may be missing the obvious here but this got me wondering.
Assuming that chemoreceptors picking up elevated CO2 enhance the DR a diver might wish to dive in a manner that will elevate his arterial CO2.
However, as the the DR involves Peripheral Vasoconstriction how does this CO2 get back to the arterial blood? This appears like a negative feedback loop which dosen't seem right.
Or is it that despite the reduced return (due to Vasoconstriction) the anaerobic metabolism generates so much more acid that the arterial blood PH drops more rapidly than if the diver was periphally vasodilated anyhow?
From my own experience I had concluded that exhale dives result in higher CO2 levels (in some cases leading to fine tremors), but I had assumed this was a consequence of lesser lung volume rather than greater production and/or less buffering in tissue.
Interesting stuff
Phil C
Auckland Freediving Club
.
Your comment "CO2 can be readily redistributed in working/vasodilated muscle." is interesting
I don't have a medical background so may be missing the obvious here but this got me wondering.
Assuming that chemoreceptors picking up elevated CO2 enhance the DR a diver might wish to dive in a manner that will elevate his arterial CO2.
However, as the the DR involves Peripheral Vasoconstriction how does this CO2 get back to the arterial blood? This appears like a negative feedback loop which dosen't seem right.
Or is it that despite the reduced return (due to Vasoconstriction) the anaerobic metabolism generates so much more acid that the arterial blood PH drops more rapidly than if the diver was periphally vasodilated anyhow?
From my own experience I had concluded that exhale dives result in higher CO2 levels (in some cases leading to fine tremors), but I had assumed this was a consequence of lesser lung volume rather than greater production and/or less buffering in tissue.
Interesting stuff
Phil C
Auckland Freediving Club
.
Well I could say mainly:
1 Why is my dynamic sucking so much compared to static?
2 Why is it that I don't feel much, if any burn after a max dynamic, while others seem to have that much much earlier?
I figure I want my muscles to shift to anaerobe mode quickly so the remaining O2 in my blood is available to my brain and heart. I now think that either my brain is using to much O2 (coordinating swimming) and or my muscles somehow manage to drain the bloodstream of O2 better than average.
The advantage of a stressed start for me are dropped expectations, which in turn prevents me estimating and tensing up in anticipation of the struggle phase.
I've read you did extensive tests with stressing yourself out to make your dive longer.
Was your brain racing and 'looping' during the breath-hold?
Any kind of thinking does cost me a lot of O2. I guess it could make up as high as 50% of total O2 consumption. What do you think?
Oh and on a last note, my CO2 tolerance may be ok, managing a nice 16x50 in 12'41". Ok, I had a nice CO2 headache after that one
LOLAnyway much thanks for your very interesting thoughts and corrections!
Love, Courage and Water,
Kars
Phil,
Yes, ".... a diver might wish to dive in a manner that will elevate his arterial CO2", but you have to be able to tolerate the elevated CO2 too ....not so easy, but there are ways to do this.
The vast majority of physiologic systems ARE -ve feedback system. Even +ve feedback systems are essentially in the end self-terminating. This is necessary to keep things homeostatic, i.e., balanced.
Its more difficult to buffer the CO2 build-up in exercising muscles when these are isolated from the central circulation. The muscles do become more acidic. Of course, when breathing resumes, or the lungs re-expand above FRC (i.e., during ascent), circulation to these vascular beds returns and there is an increase in chemoreceptor activity, resulting in a strong urge to breathe. It is entirely the case that one may, therefore, feel muscle pain/fatigue during your swim without an urge to breathe.
"..... exhale dives result in higher CO2 levels": One must remember that the lungs also act as a CO2 store, but if the volume is reduced than this storage site will be compromised. On the other hand, diving with reduced O2 stores (e.g., `empty´ lungs) also limits your BH ability and the final CO2 tension that is reached.
There are many physiologic and environmental factors to consider before, during, and post-dive that will affect the outcome. Most divers have a hard time grasping the physiology and hope for hard and fast answers, but there are no straightforward answers or singular recipe for all situations. However, if you have/develop an understanding as to what might be going on, its not difficult to plan your way to optimal results 99% of the time
Yes, ".... a diver might wish to dive in a manner that will elevate his arterial CO2", but you have to be able to tolerate the elevated CO2 too ....not so easy, but there are ways to do this.
The vast majority of physiologic systems ARE -ve feedback system. Even +ve feedback systems are essentially in the end self-terminating. This is necessary to keep things homeostatic, i.e., balanced.
Its more difficult to buffer the CO2 build-up in exercising muscles when these are isolated from the central circulation. The muscles do become more acidic. Of course, when breathing resumes, or the lungs re-expand above FRC (i.e., during ascent), circulation to these vascular beds returns and there is an increase in chemoreceptor activity, resulting in a strong urge to breathe. It is entirely the case that one may, therefore, feel muscle pain/fatigue during your swim without an urge to breathe.
"..... exhale dives result in higher CO2 levels": One must remember that the lungs also act as a CO2 store, but if the volume is reduced than this storage site will be compromised. On the other hand, diving with reduced O2 stores (e.g., `empty´ lungs) also limits your BH ability and the final CO2 tension that is reached.
There are many physiologic and environmental factors to consider before, during, and post-dive that will affect the outcome. Most divers have a hard time grasping the physiology and hope for hard and fast answers, but there are no straightforward answers or singular recipe for all situations. However, if you have/develop an understanding as to what might be going on, its not difficult to plan your way to optimal results 99% of the time
Kars,
Having a DR does not imply that blood and, therefore, O2, does not serve your muscles. Certainly, the stronger the DR the less this effect. So, probably your DR isn't pronounced enough. This could be a genetic factor or maybe you are mentally very unstressed, or both.
The more distressed you are the greater the conservation of O2, so that even if your thoughts are consuming more O2 the overall effect is for a greater overall reduction in O2 consumption. No worries there.
Being distressed in the latter phase of a dive is not the same as being distressed in the initial part of a dive. There is a world of difference. Too little, too late.
If you want to have a strong DR you have to genuinely believe that your dive will be difficult. You cannot fool yourself in this belief.....its not like that there's two of you and you can pull the wool over the other one's eyes!
Having a DR does not imply that blood and, therefore, O2, does not serve your muscles. Certainly, the stronger the DR the less this effect. So, probably your DR isn't pronounced enough. This could be a genetic factor or maybe you are mentally very unstressed, or both.
The more distressed you are the greater the conservation of O2, so that even if your thoughts are consuming more O2 the overall effect is for a greater overall reduction in O2 consumption. No worries there.
Being distressed in the latter phase of a dive is not the same as being distressed in the initial part of a dive. There is a world of difference. Too little, too late.
If you want to have a strong DR you have to genuinely believe that your dive will be difficult. You cannot fool yourself in this belief.....its not like that there's two of you and you can pull the wool over the other one's eyes!
Thanks Sebastien, I'm going to try a few things this evening. Suggestions are welcome though.
The stress I may have is that during public hours I often swim between/under surface swimmers with my mono. As you can imagine I'm not allowed to hit them, for they might loose a head and some blood. And it could happen some unaware thoughtless zombie jumps in or crosses my path walking at the shallow end. Another stress factor is the edge at 2/5th of the pool where the deep end goes shallow. And finally since it's public hours I cannot afford to BO.
Due to my long distance to the pool, work etc, on my bicycle I have a very good aerobic ability. I've got the build of a climber. So my simple thoughts go thinking that my body is very well adapted to exchanging much gas at a high level for a long time, hence it transitions later into anaerobic mode. It makes for a quick recovery, but not a long max. in my experience.
I think making the deal only to come up after the 100m would increase my mental stress levels fairly high, as well as swimming not along the wall.
To return to your preparations, can you give us a sort of general outline as to what your training program looks like?
The stress I may have is that during public hours I often swim between/under surface swimmers with my mono. As you can imagine I'm not allowed to hit them, for they might loose a head and some blood. And it could happen some unaware thoughtless zombie jumps in or crosses my path walking at the shallow end. Another stress factor is the edge at 2/5th of the pool where the deep end goes shallow. And finally since it's public hours I cannot afford to BO.
Due to my long distance to the pool, work etc, on my bicycle I have a very good aerobic ability. I've got the build of a climber. So my simple thoughts go thinking that my body is very well adapted to exchanging much gas at a high level for a long time, hence it transitions later into anaerobic mode. It makes for a quick recovery, but not a long max. in my experience.
I think making the deal only to come up after the 100m would increase my mental stress levels fairly high, as well as swimming not along the wall.
To return to your preparations, can you give us a sort of general outline as to what your training program looks like?
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I'm sorry but my way actually would not help you at all ..... I am not a good example or role model. True, if you have a high level of aerobic fitness then you body will have a strong O2-consuming response, even just in anticipation of swimming; this is a well known response in athletes. I think it is more satisfying to uncover little 'secrets' for yourself. Good luck
Well I know people's body can differ, so the search continuous. I already got some inspiration, variables and ideas to work on, and surely I'll report on DB any discoveries. I'm sure there are people who have a similar set of cards.
The training question was just mend as a nice throw back to your story, since this is actually your thread. So if you can I'm interested to hear what kind of a training phases you go through etc.
Can we expect a documentary and or some reporting of the whole endeavour?
The training question was just mend as a nice throw back to your story, since this is actually your thread. So if you can I'm interested to hear what kind of a training phases you go through etc.
Can we expect a documentary and or some reporting of the whole endeavour?
Kars,
Like you I have a very poor diving reflex. As such I have normally relied on extremely cold water as the vasoconstrictor. This is why I have such a hard time diving in the Bahamas or in warm water. I had to come up with creative methods to induce vasoconstriction in warmer water. Diving with no goggles and no nose clip certainly helped, as did using no-warm up. But more than anything, sufficient depth. If I dive over 90m the crushed chest seems to initiate sufficient vasoconstriction. On shallower dives (70m) I get much less vasoconstriction. Another trick is to have enough CO2 on the descent. Prolonged high CO2 on a slow descent gives a good vasoconstriction. Descending too fast or with insufficient CO2 results (for me) in insufficient vasoconstriction for the ascent.
My poor dive reflex (and relying on pressure to induce it), makes me pretty useless at dynamic apnea.
Like you I have a very poor diving reflex. As such I have normally relied on extremely cold water as the vasoconstrictor. This is why I have such a hard time diving in the Bahamas or in warm water. I had to come up with creative methods to induce vasoconstriction in warmer water. Diving with no goggles and no nose clip certainly helped, as did using no-warm up. But more than anything, sufficient depth. If I dive over 90m the crushed chest seems to initiate sufficient vasoconstriction. On shallower dives (70m) I get much less vasoconstriction. Another trick is to have enough CO2 on the descent. Prolonged high CO2 on a slow descent gives a good vasoconstriction. Descending too fast or with insufficient CO2 results (for me) in insufficient vasoconstriction for the ascent.
My poor dive reflex (and relying on pressure to induce it), makes me pretty useless at dynamic apnea.
Cool, at least a fellow sufferer
I went once to Egypt and for the first two days in 26,5c water there was no noticeable DR. Surreal, it felt like floating in glassy air. Taking of 1/2 a suit helped, as well as getting used to the heat and your other tips also work for me. Doing dynamics without goggles feels very nice. I keep a soft nose clip on because the water upsets my inner ear-health. Managing the ventilation to be very low greatly helps. Actually when I concentrate it feels sometimes like it's triggering a DR in my limbs
I don't know about your dynamics, but mine nearly always feel like I'm worming myself through thick water. Sometimes pieces fall into place and monofinning feels easy, effortless and like flying, those are the pb dives.
When I do a gentle very slow surface warm-up, with little or no apnea, and take a meditative warm 15min nap before my attempt that works best. The slow and warm mind, body hitting the 'cold' pool works. Though I should prevent cooling down. As for diving I found it best (haven't tried Seb's stress formula on purpose) to just do small undulations and relax and go slow awaiting the a few contractions before speeding up a notch. My head position seem important, just as the way I turn and as well as the contrast of my body/face and the water temperature.(proofed research) Actually when I think back I recall that a big part of my dynamic BO's were when my body temp got cold and I had a reduced or late DR.
For myself I think my lack of muscle and mind relaxation is something I need to work on.
I've just seen your CWT video's again and I think you could gain from a better swim technique too. Your 104m looked already heaps better then the 100m. Both great dives I dare not dream of today. And I love to see you're diving with a plan and it all comes so nicely together, just within your margins, a great skill to watch!
I wish I had some deep water and buddy nearby.
Thanks for you input and support Eric.
Kars
I went once to Egypt and for the first two days in 26,5c water there was no noticeable DR. Surreal, it felt like floating in glassy air. Taking of 1/2 a suit helped, as well as getting used to the heat and your other tips also work for me. Doing dynamics without goggles feels very nice. I keep a soft nose clip on because the water upsets my inner ear-health. Managing the ventilation to be very low greatly helps. Actually when I concentrate it feels sometimes like it's triggering a DR in my limbs
I don't know about your dynamics, but mine nearly always feel like I'm worming myself through thick water. Sometimes pieces fall into place and monofinning feels easy, effortless and like flying, those are the pb dives.
When I do a gentle very slow surface warm-up, with little or no apnea, and take a meditative warm 15min nap before my attempt that works best. The slow and warm mind, body hitting the 'cold' pool works. Though I should prevent cooling down. As for diving I found it best (haven't tried Seb's stress formula on purpose) to just do small undulations and relax and go slow awaiting the a few contractions before speeding up a notch. My head position seem important, just as the way I turn and as well as the contrast of my body/face and the water temperature.(proofed research) Actually when I think back I recall that a big part of my dynamic BO's were when my body temp got cold and I had a reduced or late DR.
For myself I think my lack of muscle and mind relaxation is something I need to work on.
I've just seen your CWT video's again and I think you could gain from a better swim technique too. Your 104m looked already heaps better then the 100m. Both great dives I dare not dream of today. And I love to see you're diving with a plan and it all comes so nicely together, just within your margins, a great skill to watch!
I wish I had some deep water and buddy nearby.
Thanks for you input and support Eric.
Kars
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Kars,
I don't think it is appropriate any longer to report on my actual approach to training. It's become all too apparent, based on some throw-away comments by what were supposedly knowledgeable but now dead divers that some of the ideas I shared were taken out completely out of context and applied in ways they never should have been. Just as disturbing, I've been credited with feats that are completely unbeknown to me and, moreover, completely untrue ... God only knows to what end.
In regards to reporting on the no-limit dives: some reporting there will no doubt be, but sorry no doco; docos require a special time committment all their own to do a good enough job of it. But, 2-3' of something is doable.
Seb
I don't think it is appropriate any longer to report on my actual approach to training. It's become all too apparent, based on some throw-away comments by what were supposedly knowledgeable but now dead divers that some of the ideas I shared were taken out completely out of context and applied in ways they never should have been. Just as disturbing, I've been credited with feats that are completely unbeknown to me and, moreover, completely untrue ... God only knows to what end.
In regards to reporting on the no-limit dives: some reporting there will no doubt be, but sorry no doco; docos require a special time committment all their own to do a good enough job of it. But, 2-3' of something is doable.
Seb