More restrictive inhale when face up with regulator

[Superlyte27]

Not what you said...

 

[timz]

Not what you said...

Please educate me. thanks.

 

[Superlyte27]

When your regulator diaphragm is above your chest the water pressure on your chest is higher than is the pressure on the regulator diaphragm. This makes it harder to breathe. Each foot of sea water is about .43 lb of pressure.

So he's right in that each fsw is worth .445psi. But since my mouth is roughly a foot above my lungs, .445psi is nothing. I doubt you are calibrated enough to detect that difference in suck factor Yes, I made that term up.

 

[timz]

So he's right in that each fsw is worth .445psi. But since my mouth is roughly a foot above my lungs, .445psi is nothing. I doubt you are calibrated enough to detect that difference in suck factor Yes, I made that term up.

Yes, but like I said. I didn't feel anything when I am hovering vertically head up. But significantly harder to suck air when I face up to the surface.

 

[Superlyte27]

There's a bubble of gas in the regulator right? After-all you've cleared the regulator, so no water, which means there's air in it. So, that bubble is trying to head for the surface. The only thing holding it in is that peice of plastic diaphragm. When you're breathing, you have to overcome that bubble's desire for the surface. When you are vertical in the water (which is sucky form by the way) that bubble is roughly even with your mouth. Not much of a pressure differential. And, all you have to do is get that diaphragm to push on that lever a little bit, and you have positive pressure whooshing into your lungs.

 

[timz]

There's a bubble of gas in the regulator right? After-all you've cleared the regulator, so no water, which means there's air in it. So, that bubble is trying to head for the surface. The only thing holding it in is that peice of plastic diaphragm. When you're breathing, you have to overcome that bubble's desire for the surface. When you are vertical in the water (which is sucky form by the way) that bubble is roughly even with your mouth. Not much of a pressure differential. And, all you have to do is get that diaphragm to push on that lever a little bit, and you have positive pressure whooshing into your lungs.

Understood. Especially with those regulators with stiffer diaphragm like Atomic. Effort required to suck in the diaphragm will be harder.

 

[Akimbo]

People are not precision instruments and there’s a lot of distraction when underwater. I’m not surprised that most people haven’t noticed the effect of position on breathing resistance.

It is a little more complex than just the pressure differential; the pressure has to be multiplied by the effected surface areas. It is very difficult to calculate the effective area the pressure is acting on your lung and diaphragm — a lot less than the approximately 1 acre of total surface area including all the alveoli for sure. However, the effected lung area is many times the area of the regulator diaphragm. It is also very difficult to measure the total force that all the chest muscles and diaphragm can exert to inflate your lungs, but it is a lot.

I am also not surprised that the OP notices increased resistance when looking up and not looking forward while the body is in vertical. The regulator diaphragm can move a good 6" higher.

I bet that the majority of divers can detect the increased breathing resistance with any front diaphragm non-servo regulator if they are relaxed in a swimming pool without a wetsuit and really concentrate. A wetsuit alone can add a lot force acting against your chest muscles. In the end it is just simple physics even though it is hard to come up with the area numbers to complete the formula.

Does this make any more sense?

 

[WarrenZ]

I havent tried it with an atomic reg but all of my other regs breath differently when I am face up underwater. It happens. Regs are optimized to breath when face down in a horizontal position.

 

[oldschoolto]

People are not precision instruments and there’s a lot of distraction when underwater. I’m not surprised that most people haven’t noticed the effect of position on breathing resistance.

It is a little more complex than just the pressure differential; the pressure has to be multiplied by the effected surface areas. It is very difficult to calculate the effective area the pressure is acting on your lung and diaphragm — a lot less than the approximately 1 acre of total surface area including all the alveoli for sure. However, the effected lung area is many times the area of the regulator diaphragm. It is also very difficult to measure the total force that all the chest muscles and diaphragm can exert to inflate your lungs, but it is a lot.

I am also not surprised that the OP notices increased resistance when looking up and not looking forward while the body is in vertical. The regulator diaphragm can move a good 6" higher.

I bet that the majority of divers can detect the increased breathing resistance with any front diaphragm non-servo regulator if they are relaxed in a swimming pool without a wetsuit and really concentrate. A wetsuit alone can add a lot force acting against your chest muscles. In the end it is just simple physics even though it is hard to come up with the area numbers to complete the formula.

Does this make any more sense?

It makes perfect sense... But the OP to say " But I felt a significantly more difficult inhalation the moment I turned myself facing to the surface "

A high quality regulator is able to flow at such a rate that you really don't notice any difference, On this last trip to Bonaire I did a video of a school of blue tangs well swimming at full speed to get the shot.. My conshelf XIV gave me all the air I wanted and at no more work then when I was just drifting along..

Jim...

 

[timz]

People are not precision instruments and there’s a lot of distraction when underwater. I’m not surprised that most people haven’t noticed the effect of position on breathing resistance.

It is a little more complex than just the pressure differential; the pressure has to be multiplied by the effected surface areas. It is very difficult to calculate the effective area the pressure is acting on your lung and diaphragm — a lot less than the approximately 1 acre of total surface area including all the alveoli for sure. However, the effected lung area is many times the area of the regulator diaphragm. It is also very difficult to measure the total force that all the chest muscles and diaphragm can exert to inflate your lungs, but it is a lot.

I am also not surprised that the OP notices increased resistance when looking up and not looking forward while the body is in vertical. The regulator diaphragm can move a good 6" higher.

I bet that the majority of divers can detect the increased breathing resistance with any front diaphragm non-servo regulator if they are relaxed in a swimming pool without a wetsuit and really concentrate. A wetsuit alone can add a lot force acting against your chest muscles. In the end it is just simple physics even though it is hard to come up with the area numbers to complete the formula.

Does this make any more sense?

I've tried different position. Horizontal body face up. Vertical with my head faces up to the surface and etc.

As long as my face faces up. I felt the increase in the resistance.

I havent tried it with an atomic reg but all of my other regs breath differently when I am face up underwater. It happens. Regs are optimized to breath when face down in a horizontal position.

Yes. I understood. I am just curious. Thanks.

It makes perfect sense... But the OP to say " But I felt a significantly more difficult inhalation the moment I turned myself facing to the surface "

A high quality regulator is able to flow at such a rate that you really don't notice any difference, On this last trip to Bonaire I did a video of a school of blue tangs well swimming at full speed to get the shot.. My conshelf XIV gave me all the air I wanted and at no more work then when I was just drifting along..

Jim...

Maybe i just need to get used to it. Though i will only face up when i blow ring bubble, checking if there's obstacles when ascent and looking for buddy.

And i am just curious if all balanced regs react the same.

Still manage to suck in air I wanted. Just increased in resistance.