What's typical buoyancy in just swim wear with no equipment?

[Nemrod]

In FW, steel 72 or aluminum 63, plastic plate I need 0 to 2 pounds of weight. In SW I might use 4 to 6 pounds.

There is no typical. Equipment, exposure clothing and people vary so much the best thing to do is to see for yourself.

I quite often will dive in a rash guard and a swim suit or a neoprene top for a little warmth. It is my favorite kind of diving because I loath wetsuits though they are a necessary evil most of the time.

I have never come across anyone who when taught the method, cannot perform a proper survival float. It is not the same as treading water. You take a breath, let yourself sink a little, perform a gentle arm scull and wide scissor, roll your head back as it surfaces, take a full breath and let yourself sink. Exhale as you do the scull and scissor and repeat. I can do this for hours and have. In fact, the practical limit is that I eventually get cold and hungry for a PBJ sandwich. I do this with my head forward snd down, some do it head up and back.

N

 

[crunchiespg]

In FW, steel 72 or aluminum 63, plastic plate I need 0 to 2 pounds of weight. In SW I might use 4 to 6 pounds.

There is no typical. Equipment, exposure clothing and people vary so much the best thing to do is to see for yourself.

I quite often will dive in a rash guard and a swim suit or a neoprene top for a little warmth. It is my favorite kind of diving because I loath wetsuits though they are a necessary evil most of the time.

I have never come across anyone who when taught the method, cannot perform a proper survival float. It is not the same as treading water. You take a breath, let yourself sink a little, perform a gentle arm scull and wide scissor, roll your head back as it surfaces, take a full breath and let yourself sink. Exhale as you do the scull and scissor and repeat. I can do this for hours and have. In fact, the practical limit is that I eventually get cold and hungry for a PBJ sandwich. I do this with my head forward snd down, some do it head up and back.

N

We were talking in basically bare skin with no equipment. Obviously with equipment and exposure suits this changes everything.

 

[Nemrod]

We were talking in basically bare skin with no equipment. Obviously with equipment and exposure suits this changes everything.

Can I at least wear my swimsuit or do I have to be naked to play? Then the answer for me is that I sink like a rock in FW and am almost neutral but still negative in SW.

N

 

[TMHeimer]

In FW, steel 72 or aluminum 63, plastic plate I need 0 to 2 pounds of weight. In SW I might use 4 to 6 pounds.

There is no typical. Equipment, exposure clothing and people vary so much the best thing to do is to see for yourself.

I quite often will dive in a rash guard and a swim suit or a neoprene top for a little warmth. It is my favorite kind of diving because I loath wetsuits though they are a necessary evil most of the time.

I have never come across anyone who when taught the method, cannot perform a proper survival float. It is not the same as treading water. You take a breath, let yourself sink a little, perform a gentle arm scull and wide scissor, roll your head back as it surfaces, take a full breath and let yourself sink. Exhale as you do the scull and scissor and repeat. I can do this for hours and have. In fact, the practical limit is that I eventually get cold and hungry for a PBJ sandwich. I do this with my head forward snd down, some do it head up and back.

N

"Drown-proofing", no? I was lucky to find out that this was "PADI legal" for the DM tread test. Though it's legal for the test, I don't think I would refer to it as actually floating, as most or all of your head is underwater a lot. Semantics maybe.

 

[Nemrod]

"Drown-proofing", no? I was lucky to find out that this was "PADI legal" for the DM tread test. Though it's legal for the test, I don't think I would refer to it as actually floating, as most or all of your head is underwater a lot. Semantics maybe.

One and the same, google it. N

 

[RJP]

I would love to meet someone - anyone - who "sinks like a stone" even with a full breath. I've had many scuba and swimming students make that claim... and in 60 seconds was able to disabuse every single one of them of that notion.

"Fat kids, skinny kids, kids that climb on rocks..."

Yes there are people who are somewhat negative, but I have yet to encounter a human body that can't stay afloat with proper breath control and stillness... and for some with a little hand scull and perhaps the occasional gentle kick now and then.

The first issue most people have is they don't understand the difference between their center-of-gravity (near their hips) and their center-of-buoyancy (mid-chest). Because the COG is lower than the COB, when in water the body will rotate around these two points until they are in vertical alignment. This rotation is confused with "sinking" because of the sensation of your legs "falling" when in fact your body is merely reorienting itself.

The second issue people have is the inefficient motions they employ to try to stay as high out of the water as possible (foolish in and of itself, only your mouth needs to be out of the water, even tilt your head back so mouth and nose is the highest point.) This is actually a 3-fold problem:

1. these motions tend to actually pull DOWN as much (or more) than they push up
2. the increased activity increases breathing rate, removing any buoyancy benefit that could otherwise have been gained from proper breath control ability
3. contracted muscles are more dense than relaxed muscles; activity actually increases your density

I'm 6'2" tall and weigh 170lbs. I swim 8-10mi and cycle 75-100mi each week so I have very little body fat. If there was a body type that was going to "sink like a stone" it would be mine. However I can float with ankles crossed straight under me, arms crossed at my chest, mouth/nose out of the water pretty much indefinitely. When I show students this they accuse me of pulling some sort of trick... until I get THEM to do it.

 

[Nemrod]

I would love to meet someone - anyone - who "sinks like a stone"
I'm 6'2" tall and weigh 170lbs. I swim 8-10mi and cycle 75-100mi each week so I have very little body fat. If there was a body type that was going to "sink like a stone" it would be mine. However I can float with ankles crossed straight under me, arms crossed at my chest, mouth/nose out of the water pretty much indefinitely. When I show students this they accuse me of pulling some sort of trick... until I get THEM to do it.

You just met one. I go down. If you read what I said, I can perform the survival float for hours. I do this by breath control and a gentle scull. I am at points during the cycle, as much as a foot below the water surface and would continue to sink but for the scull and scissor.

I am 61, swim five miles a week, bike 75 miles a week, do 3X1.5hour crossfits/strength, and use my elliptical for the equivalent of 3X6 miles per week. I am 5-11(-), 165 pounds, resting pulse 44BPM. I can no longer run, easily, due to my titanium inserts in my left leg and hip. With a full normal breath, at the surface, I will sink in FW. If I uncomfortably over inflate my lungs, packing, I float with the hair on my head brushing the surface.

You are definitely right about inefficient motions pulling people down. I would not put it that way, but yes. People who are drowning do not yell for help, do not put up a hand and count fingers like a cartoon, above the surface their heads are motionless, almost fixed, but underneath the surface they are furiously trying to walk/climb out of the water. This is some sort of human/animal fear or panic instinct. They are doing essentially the same thing you see poor divers doing, underwater walking. When I see a diver doing that I am seeing a person who but for that equipment would drown and who without that equipment would panic.

I had a collie dog, not the best dog swimmers anyways. But when he was a young dog he like to play in the water and could swim. When he got old, he could not see so good and he fell in the water from the boat dock. I was loading my parents and was about to grab him up when he backed up and fell in. My wife went in after him immediately, he was furiously pumping his legs and sinking like a lead anvil. The water was clear and I could see him and her as I went in also after both of them. My wife holding him, me holding both of them. We dried him up and fluffed him back up and consoled him as he was terrified and swallowed water. He shook it off, had a hot dog treat and we went for a ride. He got between my legs, our boat is a center console, that was his favorite boat riding spot. Me bringing them ashore, they have on life jackets for a reason:

N

 

[TMHeimer]

I tend to agree with Nemrod about still sinking with lungs full, but not sure. Have to be honest in that I have never tried this. Will give it a try next month when fishing in the Hudson. Oops, specific gravity of that water probably too high with all the bodies.

 

[Patoux01]

I would love to meet someone - anyone - who "sinks like a stone" even with a full breath. I've had many scuba and swimming students make that claim... and in 60 seconds was able to disabuse every single one of them of that notion.

"Fat kids, skinny kids, kids that climb on rocks..."

Same thing, imo it's just another one of those "I'm unique" fashion that seems to be very present these days...

 

[ronscuba]

I thought people were stating they sink like a stone when they exhale, not with a full held breath.

The average diver I see on my recreational warm water dive trips is not exactly super fit, so sinking in ocean water with an exhale is kind of unique.