Does the barometirc perssure affect free-diving

[kiwisurfa]

Hey everyone,

Whilst i was out diving the other day for some strange reason I could dive alot deeper than i could normally manage about an extra 8m! It wasn't till later that day i realized that the barometer was up to 1034. Could it be possible that is why i could dive deeper?? The higher the barometer the more air you get in your lungs?
Any help or thoughts much appreciated

cheers,
Brad

 

[devondave]

Hello Brad welcome to db.
I don't know the answer to your specific question, but here are a few thoughts.
Barometric pressure can have a severe effect on a persons mood, in some people for instance a change from low to high pressure acts as a mood elevator.
Conversely, a rapid drop can trigger bouts of depression, I have noticed this for as long as I can remember and can tell the moment the pressure drops to any significant degree, you just 'feel' it.

So my thought is this, mood has a big effect on freediving performance and maybe people who are susceptible to pressure changes perform better on high pressure days.

This is just me rambling and it might be complete cobblers, but would be interested to see if others notice the same thing.

 

[pingshui]

To me this sounds like the most probable explanation.

Your lung will not increase in size anyway. The pressure at the surface also coninues/adds to the water pressure, so there should not be increased volume under water either. Hope I get my physics right.
The only thing that the higher surface pressure would increase is the amount of gas molecules per liter, but the relation between them should stay the same. I have no idea if the increased amount of O2 per liter taken in during your last breath is big enough to have any effect. Let the experts speak! rofl

 

[Mullins]

To me this sounds like the most probable explanation.

Or.... the barometric pressure had absolutely nothing to do with it

 

[devondave]

Or.... the barometric pressure had absolutely nothing to do with it

Or. . . what he said.

 

[dimitris33]

Barometric pressure and/or weather changes may have a significant affect on human body. I found my self feel great during low humidity and North/North East wind periods and on the contrary I feel sick during high humidity and/or South/SouthWest wind periods. I can understand with my body when the weather tends to change usually a day before it change.

These affects dramaticaly my performance (I dont have measurable results to submit but this is just the way I feel) and my overall breathing becomes easier on the first case and like hell on the second. Sinuses are affected too, feeling free and clear on the first case and mid blocked on the second.

Temperature makes difference too on human body. You can see your skin and whole body feel tight during winter and like gelly during hot summer.

I believe barometric pressure affect free diving less or more depending on the person.

Even earth's magnetic field might affect freediving...who knows..! Our bodies are so little on this universe and we know so little about us....

 

[dimitris33]

Here is a nice quick from a search Human Factors in Barometric Pressure Tolerances | eHow.com

 

[Simos]

Don't listen to Mullins, what does he know about freediving?

Before we completely discard the idea (in theory you would get a bit more o2 I guess but i don't think it'd make any practical difference unless you have what Dimitris has) - what kind of depth are we talking about and what is your limiting factor usually (eg equalisation? O2? Etc)? I take it that the extra 8m make it your PB?
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[Mullins]

Obviously inhaling pressurised air will greatly increase your EQ depth, because the volume change will then be lower for any given water depth. But 21 hectopascals = 20cm of water or a 2% increase, which is not very much. And, while inhaling air at 102% of normal atmospheric pressure might give you a sliiiight advantage if your EQ was limited by volume, I'm not sure that's the case for kiwisurfa. More likely his depth is limited by technique, relaxation, water temp, fatigue and all the usual stuff.

 

[Simos]

Obviously inhaling pressurised air will greatly increase your EQ depth, because the volume change will then be lower for any given water depth.

Obviously agree that the pressure difference in question is trivial any way you cut it.

Just for the sake of argument: Not sure exactly how you meant the above Dave but I think it's not quite the same as inhaling pressurised air

Eg say you packed double the Ls of air in your lungs the pressure would be double. Therefore when you are down at 10m the lung volume will not change.

If the barometric pressure was 2atm at surface (ie double), the pressure at 10m would be 3atm and the volume would be 2/3.

So the effect of barometric pressure is even less than breathing compressed air. Am I thinking about this the wrong way? It's late here....
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[Mullins]

Yes, I was using 'pressurised' to mean increased ambient pressure.

 

[kiwisurfa]

Cheer Dave good to be here =-)

First of all when i was diving I wasn't free diving as such I was just diving for Paua or Abalone depending where your from.. I would normally only dive to about 7-8m in depth which isn't much on your guys scale but for me to be able to do about twice that it blew me away...
I have been diving for years now and never took it to serious until now, its given me the urge to get into it a bit more and see how much further i can really go..
The visibility was pretty good this day about 7m could this have some thing to do with it..? The sea temp was about 13 degrees celcius
Me and physics do not go very well together so it is interesting reading what you guys have to say.. The humidity was low this day and i'm pretty sure it was a new moon to confuse things more
That article Dimtiris makes interesting reading kind of supports my idea.?..

I don't know if I'm more confused now than when i started!!!! haha

 

[Mullins]

That article Dimtiris makes interesting reading kind of supports my idea.?

Nope, not even a little bit :t

Of course, it's possible that the change in atmospheric pressure affected performance in some genuine way. But it's equally possible it was the earth's magnetic field, or the position of Neptune, or the feng shui of the room you'd slept in the night before. Or, like you say, the new moon.

Naa you just dived better. What was limiting you previously? And where in NZ are you diving?

Edit: ahh, it's Timaru. Must be bloody cold!

 

[Simos]

Hi Kiwisurfa - haven't had time to read what Dimitris posted but for some people increased visibility does make a difference in relaxation. It's good to be able to see where you are going.

Relaxation and improved technique (esp EQ) makes a massive difference. We have a local reservoir that's 8-9m deep and 12 max at other places with very bad vis. I remember starting my open water course there a couple of years ago and I remember how hard I thought it was to get to the bottom.

After I returned the following year I kept asking what happened to the water level - I thought there was something wrong and the water level had decreased by many metres. After I helped with a few beginner courses I realised after seeing them that I was expending so much energy at first and that the level was the same. Now whenever we go it feels that the bottom is only a duck dive away.

EQ can take a huge amount of effort - did you have trouble EQ before that was resolved in this dive? Diving to 7-8m sounds to me like EQ might have been your issue (might have missing one of the early EQ and riding ears to 7-8m?).

One thing's for sure: you def have the breathold ability to go deeper than 7-8m. I would say everyone does. A nice relaxed duck dive will take you at least 3-4m down so basically you only have to swim another 4m to get to 8m and then you can just float back to the surface.

The other thing I can think of is whether your boyancy changed? Did you use different weights/suit?
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[kiwisurfa]

Haha yeah i think it must of been the Feng Shui of my room for sure that stuff is hetic!!!!!
Yeah Timaru water does get cold Ill still get out there in winter when it gets to 8degrees or colder... I have always managed to EQ fine well I have thought that I have been able to, There have been days in the past where i have had trouble but that would be mainly due to having a cold etc..

My bouyancy i'd say would of been greater as It is getting colder here and i have increased my wetsuit thickness. I probably was more relaxed this day not sure why maybe i was more focused to get down to the bottom...