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Tom Sietas 213 m DNF !!!!!

Thread Status: Hello , There was no answer in this thread for more than 90 days.
It can take a long time to get an up-to-date response or contact with relevant users.
One of the reasons Tom is able to keep a low hart rate at the start is because he does not inhale to the max using lots of muscle efford , but after a big below max gulp gradual fills up his lungs to way above max by small (but lots and lots and lots) of packs.
Well, the muscle work may add or save some beats per min, but the main part of it is not caused by increased physical effort during the hyperventilation, but is it a plain and simple physiological reaction on the lower level of CO2, so hyperventilating in a relaxed way does not really explain the low heart rate before the submersion. However, low heart rate before the immersion is not really desired. Quite the opposite - you need rather quick heart rate to push the blood through the body faster, hence oxygenating the blood (especially the venous part) and tissues better. Unfortunately it is much more complex, so there are some disadvantages too, but generally high heart rate before the immersion, and low rate as soon as possible after the start of apnea are desired.

Regarding neckweights. Lots of people underestimate how much you need for a perfect trimmed body in nofins. Even with my small 6 liter lungs and only a 3 mm pants i need around 3,5 kg's to be perfectly horizontal.
Yes, that's right - I have even smaller lungs, and use 2.5 kg without any wetsuit. And I believe Tom's 10 l are without packing (or am I wrong?), so with his rather extreme packing, he probably gets in much more.
 
Yes, that's right - I have even smaller lungs, and use 2.5 kg without any wetsuit. And I believe Tom's 10 l are without packing (or am I wrong?), so with his rather extreme packing, he probably gets in much more.

You may be right since i remember when I was assisting him during one of his world records some time ago with his neckweight, the thing alone was already 10 kilos. And he also has some weights his hips.
 
In regard to the dive itself, there is a little boyancy change happening during a long dynamic. So it's important to choose one's weights wisely, not to be nutral in the beginning, but struggleing to stay of the bottom in the end for instance.
Buoyancy change due to what...suit compression? In the article, regarding this Tom is quoted saying (imperfect translation), "Because you use even air, which means your lungs during the dive smaller, about the output." Sounds like he's just commenting that you need a bit more air because the lungs compress as one descends into the water, but I don't know why he would have said that a bit of "lift" is needed initially. (I'm not talking about the elevator).

I'm concerned about this because I have started many dynamics just slightly buoyant because I didn't fill my lungs with precisely the right amount of air, and this has always only been detrimental for performance for me.

I believe Tom's 10 l are without packing (or am I wrong?), so with his rather extreme packing, he probably gets in much more.
According to the article:

  • 'Using a technique called "packing", he is now able to up to three litres of air into his lungs in addition to press and so a total of nearly ten litres of water below.'
7L, then?
 
Buoyancy change due to what...suit compression?
It is because of oxygen consumption. The oxygen in lungs used during the apnea is not fully replaced by the same amount of CO2. However, the volume change is rather minor, roughly around 2-5%, perhaps a percent more in extreme cases.

EDIT: on the other hand, at heavy packers, the volume change after a long apnea would be reduced - it would not reach the numbers mentioned above. Although packing increases the lung volume, it also increases the inner pressure. And as oxygen gets consumed, the pressure decreases until it is back to normal. Only then the lung volume starts to decrease. Well, in reality both effects (volume and pressure change) run at least to certain point simultaneously, but anyway only part of the oxygen consumption will translate into buoyancy loss. I would need to look up more exact data to give you a realistic buoyancy change estimate after a max apnea, but my uneducated guess would be somewhere between 1% and 3%, perhaps 4% at very max (but I rather doubt it).
 
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I think Dave could weigh in on the issue of decreased buoyancy at the end of a swim, as it's something he has to deal with. It's also interesting to hear about the hyperventilation, as it's the exact opposite of what most guys over here are going for.

As for weighting, I'd be surprised if Tom only has 10kg on. I thought he was wearing a 5mm suit and estimated he'd have ~15kg, but even with a 3mm I would think he'd need 12+. Maybe it was just the neckweight?
 
Psst, I know Tom's secret recipe:
2895[1].jpg
 
Trux,

Can't remember I gave you permission to publish a picture of my in-house static training pool. :naughty
Please check next time before you violate my privacy this way.
 
Can't remember I gave you permission to publish a picture of my in-house static training pool. :naughty
In fact it is for dynamic too - if you zoom the picture, you would see you can swim under the bridge too, so you can train dynamics in endless circles.

That proves it is not your bedroom :)
 
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