[The Scientist (OP)]

Please explain the technique as detailed as possible. Thank you.

[Bored chemist]

People have (generally) an average density less than that of water.

[The Scientist (OP)]

People have (generally) an average density less than that of water.

But they do sink at times even when they are not carrying anything.

So what is the way to stay afloat then?

Thanks.

[syhprum]

High density people (ie skinny ones) have the same problem as sharks with no swim bladder the best they can do is keep their lungs inflated as much as possible and keep moving forward so that their body acts like the aerofoil shape of an aircraft wing that keeps a plane in the air.

[Bored chemist]

I'm fairly skinny and I can swim. I keep my lungs at least partly inflated. Also, I guess I always swim "uphill" so I stay above water.

[Geezer]

I think everyone can float on their back in seawater. I'm not sure that applies in fresh water.

[Karen W.]

Every time I try to float on my back my bottom and center sinks cause my back is not strong enough to arch it up enough...Now on the flip side...I can do the dead mans float face down just fine.. So whys that?
I have trouble floating at all unless I wear a waist floatation use fins and a kick board.... or pool bar bells. I can however once again swim face down for 15 ft or so.. but these days I cannot hold my breath to save my life! Is my weight what sinks the middele or the lack of arch and air power..?
I always thought it was soley to do with lung inflation as noted above..

[imatfaal]

The density of a human body is damned close to that of water (within one percent) - so we tend to float very low in the water, especially if that water is fresh.  the problem many people find with 'just floating' is that they want their whole head and maybe even hands above water.  this represents far too much of our body to be supported by the displacement of water by the rest.  to float without kicking or treading water you must be willing to only have the very front of your face above water and not care if the occasional wave/ripple goes over you .  once you can overcome the mental barrier - it is an immensely relaxing position.  if you cannot manage this then just try making small movements with your hands (arms hanging loose - push down slide up) this should provide enough to keep head above water.  Matthew

ps writing this has made me want to swim in the sea so much - now looking for holiday

[Karen W.]

Thank you Mathew I will have to practice.. you are right I do have a horrible fear of the water not as bad as some but still its there... I drowned once and was resuscitated and had two more near drownings which scared the holy soup right out of me.... so I do have exactly the worries you pointed out! Thank you...

[Geezer]

When I was a kid, I started snorkelling in the sea before I could swim properly! I used to float face down for ages.