At what bodyfat percentage do people float in fresh water?

jamesakrobinson

I know most people float... I have been a sinker most of my life, with a couple of years in my 30s when I got pudgy and could actually float.
Now I have been staying around 8 to 9% for a while and I sink directly to the bottom of a pool (it's actually even a saltwater pool but not very concentrated). I can easily actually walk across the bottom from one end to the other (lung capacity is the limiting factor. I have to come up for air partway back). I am always delighted when I go to the Caribbean and can float easily so I am toying with the idea of bulking up a bit over the winter to see if I can get to at least neutral buoyancy... I will curtail the experiment if I start to dislike what I see in the mirror but I need some kind of target to shoot for. I figure I can hit an indoor pool to test progress from time to time.

jdlobb

I was a varsity swimmer in high school and stood at about 18-20% bf, I was almost perfectly neutrally buoyant. A deep breath would make me float, exhaling would make me sink like a rock.

jamesakrobinson

Thanks!
I will experiment with bulking up to close to those numbers and see what the results are.

ContraryMaryMary

I don't think it's a particular body fat percentage, but a body composition thing. My sister has always been thin and is very buoyant - to the point she can read a book while lying on her back in the pool. I'm a sinker - when chubby or thin - if I don't keep my arms moving while floating on my back I head straight to the bottom. A conversation with a local swimming teacher indicates some people are floaters, some sinkers, regardless of how fat they are. Someone else suggested bone density could be a factor... I'd be interested in how your experiment turns out.

canadianlbs

i know there are parts of me that are always going to float . . . . sigh.

usmcmp

I have always floated. Obese, skinny, shredded, pregnant, wearing clothes, holding a rifle while wearing a flak jacket and boots, doesn't matter. It's not a body fat percentage thing.

jamesakrobinson

Hmmm... I intend to let myself gain a bit of fat over the winter anyway so I will continue the experiment until either I float (like in my 30s), the mirror tells me to back off, or my blood pressure goes up.
I will update this thread with the results.

On the subject of bone density... I get a Dexa every 6 months to track my progress and according to the report my bones are more dense than the average 20 year old man... I'm certain that's the result of squats and deadlifts. (glad those hateful exercises show a measurable benefit!)

mph323

For what it's worth - when I was overweight I had a really hard time staying seated in the spa. I kept floating up, and really had to anchor myself to prevent it. I'm at the lower end of my BMI now and I can sit solid on the seat with very little anchoring involved. I've put on a little muscle, but the difference mostly is just the general change in body fat as I lost weight. I just realized this a few weeks ago

middlehaitch

I have always been a good floater and never been overweight ( a brief spell of over fat though)
Most of my life I have weighed between 98-105lbs at 5'1.

I found it hard doing aquafit because I kept floating instead of being able to keep my feet on the bottom of the pool.

I too have heard it connected to bone density, I would say I was small-ish boned. I don't know if there is any connection or if it is just an old wives tale.
Hope someone will produce a nice bit of science (hint, hint )

Cheers, h.

Unknown

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sijomial

Only the top two inches of my head are above water when I float. Unfortunately my nostrils aren't on the top of my head....

Always been the same whether I was slim, fat or muscular. It's made me wonder about the accuracy of hydro-static body composition testing.

middlehaitch

sijomial wrote: »

Only the top two inches of my head are above water when I float. Unfortunately my nostrils aren't on the top of my head....

Always been the same whether I was slim, fat or muscular. It's made me wonder about the accuracy of hydro-static body composition testing.

I've always had a bit of a giggle when I read about that- I don't know how I could be kept under the water unless I was tied down.

Cheers, h.

jesspen91

I like to say I have two permanent flotation devices attached to my chest...

stevencloser

middlehaitch wrote: »

I have always been a good floater and never been overweight ( a brief spell of over fat though)
Most of my life I have weighed between 98-105lbs at 5'1.

I found it hard doing aquafit because I kept floating instead of being able to keep my feet on the bottom of the pool.

I too have heard it connected to bone density, I would say I was small-ish boned. I don't know if there is any connection or if it is just an old wives tale.
Hope someone will produce a nice bit of science (hint, hint )

Cheers, h.

Well, uh.... this exists.

http://kirschner.med.harvard.edu/files/bionumbers/Density and mass of each organ-tissue.pdf

I don't want to think about how they found that out.

stanmann571

stevencloser wrote: »

middlehaitch wrote: »

I have always been a good floater and never been overweight ( a brief spell of over fat though)
Most of my life I have weighed between 98-105lbs at 5'1.

I found it hard doing aquafit because I kept floating instead of being able to keep my feet on the bottom of the pool.

I too have heard it connected to bone density, I would say I was small-ish boned. I don't know if there is any connection or if it is just an old wives tale.
Hope someone will produce a nice bit of science (hint, hint )

Cheers, h.

Well, uh.... this exists.

http://kirschner.med.harvard.edu/files/bionumbers/Density and mass of each organ-tissue.pdf

I don't want to think about how they found that out.

Presumably autopsies

middlehaitch

stanmann571 wrote: »

stevencloser wrote: »

middlehaitch wrote: »

I have always been a good floater and never been overweight ( a brief spell of over fat though)
Most of my life I have weighed between 98-105lbs at 5'1.

I found it hard doing aquafit because I kept floating instead of being able to keep my feet on the bottom of the pool.

I too have heard it connected to bone density, I would say I was small-ish boned. I don't know if there is any connection or if it is just an old wives tale.
Hope someone will produce a nice bit of science (hint, hint )

Cheers, h.

Well, uh.... this exists.

http://kirschner.med.harvard.edu/files/bionumbers/Density and mass of each organ-tissue.pdf

I don't want to think about how they found that out.

Presumably autopsies

You weren't supposed to let me know! h

Thanks @stevencloser

CSARdiver

10 - 15% Body fat per the Naval Special Warfare Command

canadianlbs

stanmann571 wrote: »

Presumably autopsies

and a bucket of water. i hope.

richardgavel

It's simple physics. Something floats when the weight of the item displaces an amount of water whose weight is equal. So 2 people wildly different could both float, but one could end up with half their body above the surface and another just a small portion above the surface (heavier, but displacing more water)

lorrpb

middlehaitch wrote: »

sijomial wrote: »

Only the top two inches of my head are above water when I float. Unfortunately my nostrils aren't on the top of my head....

Always been the same whether I was slim, fat or muscular. It's made me wonder about the accuracy of hydro-static body composition testing.

I've always had a bit of a giggle when I read about that- I don't know how I could be kept under the water unless I was tied down.

Cheers, h.

You stick you feet under a bar and place weights on your legs.

middlehaitch

lorrpb wrote: »

middlehaitch wrote: »

sijomial wrote: »

Only the top two inches of my head are above water when I float. Unfortunately my nostrils aren't on the top of my head....

Always been the same whether I was slim, fat or muscular. It's made me wonder about the accuracy of hydro-static body composition testing.

I've always had a bit of a giggle when I read about that- I don't know how I could be kept under the water unless I was tied down.

Cheers, h.

You stick you feet under a bar and place weights on your legs.

Awww, I was quite enjoying the thought of my head keep popping up and down like some aquatic jack-in-the-box.

Makes sense though. h.

Need2Exerc1se

richardgavel wrote: »

It's simple physics. Something floats when the weight of the item displaces an amount of water whose weight is equal. So 2 people wildly different could both float, but one could end up with half their body above the surface and another just a small portion above the surface (heavier, but displacing more water)

Yeah, it would never be a specific BF%. The amount of muscle would be a bigger determining factor than the amount of fat I think, since muscle is more dense.

bpetrosky

CindyWard2

I am bottom heavy, bubble butt...I can't sink to save my life...can't make it to the bottom of a pool, can't lay on the bottom like hubby can...my butt always floats up...no joke...I have my own, on board personal flotation device!!

Aaron_K123

Difficult to answer given that increasing bodyfat in some scenarios might actually decrease rather than increase buoyancy. Given buoyancy is a factor of the mass of the volume of water you displace versus your own mass it comes down to if adding fat to your body increases it's volume more than its mass relative to water. For subcutaneous fat definately yes, but for visceral fat I am not as sure.

A metal boat floats despite metal being denser than water because the shape of the boat displaces more water than the boat weighs. Fat is much less dense than metal and by itself floats. So what would happen in you put 10 tons of fat into a boat....would the boat be less buoyant and sink a bit into the water or become more buoyant and float higher in the water. I think there it's pretty clear adding fat would make the boat sink because the mass of the boat increases but it's shape and volume do not.

So if you are at 8% bodyfat and go up to 10% but all of that fat is visceral and in your internal cavity does that increase the volume of your body (your external shape) or not? I'm not entirely sure.

GottaBurnEmAll

jesspen91 wrote: »

I like to say I have two permanent flotation devices attached to my chest...

I have always been gifted in that department and I still sink like a rock. Fat, thin, it doesn't matter.

pogiguy05

I am about 26% BF I think bit I have always had no problems with floating. The key for me is lung capacity. I can lay on my back and float and just have to take quick deep breaths to stay completely afloat. I would have to say everyone would be different depending on bone density and all that.

For those of you who cannot seem to sink you can get a weight belt that would help with that. Just when your dialing in how much weight do it in shallow water.

You would be surprised that in scuba gear as you see in my pic I am only carrying about 6lbs. However, back home in cold water with all my gear I carry about 32lbs for me to be able to sink below the surface.