why can’t you float in water forever?


Seems like you can float on your back forever, without really getting tired. When people drown in lakes or oceans, why can’t they just float until someone rescues them? I get it if you’re wearing clothes heavy with water, but if you were already swimming, or at least dressed for it…?

In: 851

There’s several reasons:

Any water that is not at least as warm your own body temperature will over time cool you down so you’ll experience hypothermia.

At the same time, you’ll start cramping up and also getting tired.
Because it’s just a little harder to breathe when your chest isn’t at surface level, you’ll usually kick your feet every now and then to come up a little to make it easier to breathe which contributes to you getting tired.

Also, when you’re in the ocean, the waves are a factor because they can easily prevent you from breathing properly. The animals of the ocean are another topic altogether.

One more problem is that people who realise that they’re having a problem in open water don’t usually stay calm and collected but panic, use up their energy and try to fight the water.

Last but not least it’s hard to keep your head in a position that makes breathing easy enough for hours or even days on end.

So although it’s quite possible to float for a LONG time given the right circumstances, it’s not that easy.


Sure if the water is pretty calm, it is possible to float with little effort. There are other problems though

a) Hypothermia. Humans lose heat fairly quickly in water.

b) Thirst. Can’t drink sea water. Humans don’t survive very long (few days to a week at most) without water. And seawater will dehydrate the body.

c) Most open bodies of water aren’t very calm. So it will take a bit of energy to remain floating. While it takes a fair bit to die from lack of food, humans can run out of energy fairly quickly.

d) Exposure to the sun. Also a problem. Mild sunburns might be not more than a nuisance. But major problems like infections etc can and will occur with major sun burns. Sun exposure also leads to heatstroke etc.

Ultimately, without protection from the sun, relatively calm seas, the dehydrating effects of sea water, a source of fresh water to drink, food and protection from the cold as well, floating even for even a day without assistance is difficult.

If you don’t have a life jacket and are able to stay calm without trying to swim then ideally as long as you can breathe and inflate your lungs you can float, but you can’t stay awake forever. There are more ways to die in open water than just drowning. Sun exposure, hypothermia, dehydration. Maybe a shark eats you or maybe your skin just rots from being in the water so long.

Because while it seems easy, its not as easy as just lying down. You will need to constantly exert at list a bit of force to keep yourself in the correct position. You can easily test this by trying to float for a few hours. It will get tiring pretty fast.

Combine that with hypothermia due to water constantly sapping away your body heat, and you will get exhausted pretty fast.